Regular readers of SAR will no doubt recognize the name Michael Heidler, as he is has contributed numerous articles over the years. He has also authored several books on military topics in his native German language. His latest book (entirely in English) does a splendid job of covering all aspects of the M3 and the later M3A1 variant. This is fortunate as the Thompson submachine gun tends to get the lions share of attention when discussing American SMGs.

The M3 “grease gun” was designed as a low-cost, simple-to-produce submachine gun, much like the German MP 40 and the British Sten SMGs. Made from simple stampings of sheet metal, rather than requiring many complex machining operations, these guns could be produced far faster than “old-school” guns like the Thompson.

As noted in chapter 1, Introduction, the U.S. Ordnance Department realized the need for such a design as early as 1939. The next two chapters build on this theme, with chapter 2 briefly describing the Model 1921 and 1928 Thompson guns, the Reising Model 50, and the very short-lived Hyde-Inland M2. This is followed by chapter 3 detailing the series of trials that led to the selection of the T-20 (renamed the M3 upon formal adoption.) Nine designs are profiled as part of the first phase of the trials, and 12 types that took part in the second phase are discussed. Several of these were existing foreign designs included for comparison only. These include the Finnish Suomi M/31, the British Sten Mk. II and Mk. III, and the Australian Austen Mk. I.

Heidler covers the early development stage as the T-20 went through further testing, including photos of a “dust test” wooden box. Having passed the dust test and a mud test, the gun was officially named the U.S. Submachine Gun, Caliber .45, M3.

This book has a great blend of WW II era B&W photos, patent drawings, U.S. Army illustrations (mostly from technical manual TM 9-217 and field manual FM 23-41), and modern-day color detail photos. There is also a nice collection of photos and artifacts from the Guide Lamp division of General Motors. The Guide Lamp plant in Anderson, Indiana produced 688,975 grease guns during WWII.

The Accessories chapter has a good selection of the bits and pieces that gun collectors love to collect. Items shown are: oiler, brush, extractor tool (to remove the extractor pin.), sling, magazines, mag loader, mag pouches, large and small pouches for spare parts, and the M9 flash hider.

Chapter 14, The Grease Gun in Combat, is almost entirely photographs and captions, with only about one page of text. Naturally, most photos are from WWII, but there are several from Korea, Vietnam, and even Afghanistan and Iraq.

This leads to the next chapter, Use in Foreign Countries. Some nations were supplied with the M3 by proper means, while other countries just managed to get them somehow. China is an interesting example. As Japan was at war with both the U.S. and China, it was logical that the U.S. would assist China during WWII. After WWII ended, China went back to fighting with itself; it had been involved in a civil war between the Communists and the Nationalists since 1927, pausing during the Japanese occupation. Eventually, the Nationalist forces withdrew to the island of Taiwan in 1949. But before this withdrawal, in 1947, the Nationalists set up a factory to produce near exact copies of the M3A1. This was named the Model 36. Shortly afterwards, in 1948, a version in 9x19mm entered production. This was called the Model 37. Soon, the Nationalists evacuated to Taiwan. There, they set up a new arms factory to produce an updated version (also in 9x19mm) called the model 39. Meanwhile, the Communist forces took over the original factory and began building the model 36 in 45 ACP once again. Heidler goes into more detail on this subject, of course. Numerous photos of the different variants are featured, including close-ups of receiver markings.

Argentina also produced their own version of the grease gun, called the PAM 1, and later the PAM 2. The difference was the PAM 2 had a grip safety added to prevent accidental firing if the gun was dropped. Both types were chambered in 9x19mm. Again, numerous color photos are given.   

This is a fine quality book from a respected author, covering a gun that has been overshadowed by a sibling. I hope that Heidler and Schiffer Publishing collaborate on more titles. I would love to see some of the Soviet SMGs covered in similar detail.

SPECIFICATIONS

• Title: The US M3/M3A1 Submachine Gun: The Complete History of America’s Famed “Grease Gun”
• Author: Michael Heidler
• ISBN: 978-0-7643-6058-9
• Copyright: 2020
• Binding: Hardcover with matching dust jacket
• Size: 8.5 x 11 in.
• Pages: 224 pages
• Photos: 551 B&W and color photos and illustrations
• Publisher: Schiffer Publishing Ltd.
• Website: schiffermilitary.com
• MSRP: $45

by Pierangelo Tendas

From 1969 to 1988, Italy bore the brunt of the wave of political terrorism that hit Europe as a whole: bombings, shootings, kidnappings, robberies, and attacks against law enforcement, politicians, and magistrates by both extreme left-wing and extreme right-wing militant armed groups ended up killing over 400 people and wounding well over 1000. On top of this, the 1970s saw the rise of international terrorism, particularly by radical Middle Eastern groups; from 1973 to 1989, attacks by Palestinian terrorists against Italy and Italian assets all through the world killed 66 people and wounded more than 130.

Just like their counterparts more or less all over the world, the Italian firearms industry went on to study numerous solutions that could integrate the lessons learned from both the experience of law enforcement operators and that of the militaries in the recent conflicts around the globe – last but not least, the American experience in Vietnam – into practical solutions to tackle this kind of threat. Some would be more commercially successful than others, although, as in many other cases, more often than not, the most interesting products would be the brainchild of this or that underdog.

Headquartered in the city of Turin, the Società Italiana Tecnologie Speciali S.p.A. company (“Italian Company for Special Technologies, Ltd.”), best known by the acronym SITES, was established and led by two engineers – Roberto Teppa and Claudio Gritti, with a third engineer, Franco Manassero, acting as the CEO – spent some time evaluating the pros and cons of existing firearms in an attempt to create what would be the best all-round sub-machine gun for all law enforcement uses… from patrol (most law enforcement back in the day, and still today, relying on SMGs as their patrol long guns in lieu of the shotguns and semi-automatic carbines more popular in the U.S.) to close protection, from special operations to counter-insurgency.

The first iteration of their project, called the Spectre Model 2, was first showcased in 1983 and began production in 1985. By 1988, a few modifications concerning the manufacturing specs of certain components were implemented; the changes are detailed in our article by J.M. Ramos published on SAR V4N8 (May 2001), Volume 4. The result, dubbed the Model 4 – or SITES Spectre M4 for short – was manufactured by SITES from 1988 to 1998, with some variants still being assembled as late as in 2001.

Italian Innovation

In the highly competitive field of small arms manufacturing of the 1980s, the SITES Spectre was a blend of tradition and innovation. Built around a stamped steel receiver, with a trigger group assembly manufactured out of the same materials and very little synthetic components outside of the pistol grip and its foregrip, the Spectre wasn’t a featherweight by a long shot, weighing in at 2.9 kilograms (about 6.4 pounds) when empty.

What made it absolutely unique was its technical layout. Teppa and Gritti wanted the SITES Spectre to be ready to deploy and operate at a moment’s notice, without sacrificing performance, reliability, or safety. As strange as it seems, they did so by doing without a manual safety. The SITES Spectre was the world’s first sub-machine gun – and as of today, it remains the only mass-produced SMG – to employ a SA/DA trigger with no external safety, replaced by a decocker.

A half-moon selector, located right above the trigger guard on both sides and activated by the shooter’s index finger, only provided two positions – “S” for semi-automatic, and “F” for full-automatic. An ambidextrous lever located at thumb reach over the pistol grip could be activated to decock the gun, requiring a deliberate, long trigger pull to fire off the first shot, with all subsequent shots being fired in single-action. This made accidental or negligent discharges of the SITES Spectre basically impossible while still keeping the gun always ready for action.

The SITES Spectre was a hammer-fired, delayed-blowback, closed bolt design, with a peculiar two-part bolt and a dual recoil spring. When a round is chambered, the front portion of the bolt, which also houses the firing pin and the extractor, moves forward while the rear portion remains locked back, engaged to the sear, and acts as a hammer, to be released on the striker when the trigger is pulled. Both components travel rearwards together after the SMG is fired, but once the empty case is extracted and ejected, only the front portion slams back forward, loading a fresh round in chamber while the rear portion engages the sear and stays locked back until the trigger is pulled again. The timing of the interaction between these two separate masses creates the opening delay that makes the SITES Spectre safe for use in all calibers it was built for – but we’ll talk about those later.

Additionally, the two-part bolt was advertised as a “forced convection” device, a safety feature against overheating: the alternate movement of the two components would pump air around the chamber and the barrel, reducing the temperature of the system during sustained fire and thus the danger of a cook-off. That may seem redundant – a closed-bolt firearm is definitely more prone to cook-off than an open-bolt firearm, but a sub-machine gun is hardly the kind of weapon that will likely experience a cook-off – but, if anything, the bolt design also had the advantage of reducing moving masses at any given time, thus making the SITES Spectre extremely stable and controllable, with very low felt recoil and muzzle climb, and reliable even with high or very high-pressure ammunition (it was rated for 9mm Luger up to +P+ by the Italian military and government entities that procured it.)

Readily Ambidextrous, Suppressor-ready

Aside from the previously mentioned ambidextrous selector and decocker, the only other controls on the SITES Spectre are the non-reciprocating charging handle and the magazine release catch.

The former is located on top of the receiver and consists of a flat polymer lever with two serrated studs on both sides. An improvement from the first-iteration Model 2 (which featured an UZI-style cocking knob), the charging handle of the SITES Spectre M4 can be operated by the shooter’s index finger and thumb, with either hand, and doesn’t interfere with the sighting plan, nor with the position of the buttstock.

The magazine release is a flat button located within the trigger guard, just behind the magazine well, and by pushing it with their trigger finger, the shooter releases the hook that retains the magazine in place. Both controls can be operated by left-handed or right-handed shooters, making the SITES Spectre one of the very first fully ambidextrous firearms of modern times.

The SITES Spectre M4 fed through proprietary quad-stack, single-feed magazines manufactured out of sheet metal, inspired (at least in concept, if not officially) by the Finnish Suomi KP/31 “coffin” mags, and offered in two capacities – 30 and 50 rounds. The 30-round magazine was as tall as a pack of cigarettes, while the 50-round mag was as long as a standard 30- or 32-round mag used by any other SMG of the time. Reduced masses made the SITES Spectre more easily concealable – a plus for law enforcement operators working close protection details – while still packing enough ammunition to engage in sudden, high-intensity firefights and get the upper hand.

The SITES Spectre was fitted from factory with a 13 cm (5.11-inch) barrel, with a rather unusual sinusoidal rifling; similar in concept to the Sabatti MRR Multi-Radial Rifling pattern of modern manufacture, the SITES Spectre’s sinusoidal rifling consisted essentially of polygon rifling with softer edges between lands and grooves, which the bullet was thus allowed to fill better, acting as a gas seal as it traveled through the barrel, allowing very little (if any) gas to escape around the lands and maximizing propulsion efficiency.

Upon request, the SITES Spectre M4 could be obtained with a slightly longer, threaded barrel that would take a purpose-built silencer, manufactured entirely out of steel and dubbed the EM-F2. The sinusoidal rifling and the “gas seal effect” it achieved made the EM-F2 suppressor particularly effective, even with supersonic loads.

The SITES Spectre came from factory with an up-folding sheet metal stock, held in the closed position by a metal clamp that engaged the top ventilation holes of the barrel shroud and was thus very easy to deploy and not nearly as uncomfortable as other sheet metal stocks of sub-machine guns from the same era. The stock was cut on top – a reminiscence of the Model 2 pre-production model, where the stock had to have clearance for the UZI-style cocking knob – and even when closed, provides unobstructed view of the sights, specifically a fixed polymer rear sight and an elevation-adjustable front post, zeroed from factory for a 50-meter range (about 164 feet).

The SITES Spectre M4 strips very easily: with the chamber clear, hammer down, and magazine removed, the user only needs to open the stock and pull out the passing pin that integrates the rear sling swivel – which can be installed to the rear or left side, by the way – in order to remove the receiver end cap with the recoil springs and guide rods and slide the two-part bolt out. At this point, the entire trigger group assembly is removed from the bottom of the receiver. Additional stripping includes the removal of the barrel, which requires the use of a hex key to loosen the barrel retaining block nut.

Multicaliber… But Not Exactly

The SITES Spectre M4 was initially advertised as being available in three calibers: 9mm Luger, 45 ACP, and later, 40 Smith & Wesson. In reality, virtually all the select-fire Spectres still in existence are in 9mm Luger, and their recorded cyclic rate in full-automatic fire ranges between 850 and 900 rounds per minute, with the utmost level of reliability; the issues with the selector experienced by a well-known Guntuber with a full-automatic SITES Spectre in early August this year are to be attributed to the wear and tear and lack of maintenance of the individual firearm being tested rather than to inherent engineering or manufacturing issues.

The ergonomics of the SITES Spectre M4 were very reminiscent of those of the Beretta PM-12S, Italy’s main service sub-machine gun of the day. The Spectre might have been considered significantly superior due to the closed bolt operation and ambidextrous capabilities, but its lack of widespread acceptance and adoption among Italian government, military and law enforcement customers came down to the Italian authorities’ long-rooted reluctance in subjecting their personnel to extensive retraining. This, and in the fact that SITES was, after all, a small company, incapable of meeting the production volumes that a major government contract would entail.

This said, certain special units within the Italian military and law enforcement communities did procure significant quantities of the SITES Spectre M4, which was deployed as late as during the Italian participation to ISAF and the circa 2015 Resolute Support Mission in Afghanistan. Confirmed international customers include Switzerland, France, and in the early 1990s, the South African Defence Forces and the governments of the freshly independent Croatia and Bosnia and Herzegovina.

SITES also manufactured three semi-automatic variants of the Spectre M4 for international commercial sales to civilian shooters and private security personnel, dubbed respectively the “Falcon,” the “Spectre HC,” and the “Ranger.”

The SITES Falcon was the civilian version of the Spectre M4 as sold in Italy; chambered in 9×21 IMI but also available in 40 Smith & Wesson and 45 HP (45 ACP would remain banned for civilians in Italy until the year 2000 and 9mm Luger wouldn’t be made legal until the year 2022), the Falcon was an outright Spectre M4, with the lack of select-fire capabilities but retaining the original foregrip and upfolding sheet metal stock.

The Spectre HC was the version for the U.S. civilian market, available in 9mm Luger, 40 Smith & Wesson, and 45 ACP, and imported first by FIE Inc. of Hialeah, FL then by American Arms, Inc. of Garden Grove, CA.

In order to comply with the 1934 National Firearms Act and the 1968 Gun Control Act, the Spectre HC came equipped with a manual safety located where the fire selector on the Spectre M4 would be, and of course didn’t feature either the upfolding stock and the foregrip of the original, which largely reduced its ergonomics. The Spectre HC was banned by name by the 1994 Assault Weapons Ban and by similar state laws passed around the same time, in effect killing the presence of the SITES Spectre on the U.S. market.

Last, the SITES Ranger was a pistol-caliber carbine version for the Italian civilian market; manufactured in a handful of samples in 9×18mm Police, then solely in 9×21 IMI, the SITES Ranger was essentially the same as the Falcon, only with a slightly longer, unthreaded barrel. In order to comply with the Italian laws of the time, the stock of the SITES Ranger was locked in the open position and the 30-round magazine was pinned to a maximum capacity of 10 rounds (the same as the SITES Falcon, pistol, its magazine was similarly pinned to 15 rounds); but by “pinned” we mean literally, as the company used simple non-rebated passing pins that Italian shooters could, and often did, remove with a simple pin punch, returning the magazines to the original capacity and the stock to full function.

A 16-inch barrel PCC version of the Spectre was advertised briefly on the U.S. market, but, to our knowledge, not many were actually imported. FIE imported approximately 1,500 Spectre HC pistols, all in 9mm Luger, while American Arms imported a gross total of 4,000 samples, over 3,500 of which were in 9mm, only 300 in 40 Smith & Wesson, and less than 100 in 45 ACP.

When SITES closed permanently in 1998, the existing stock of parts for the Spectre M4 and its civilian counterparts was picked up by Claudio Gritti, who moved to Lugano, Switzerland, and established his own company – Greco Sport S.A. – which continued to assemble and sell them until 2001. The legacy of the Spectre M4 lives own, however, with BCM Europearms of Italy still working on the PM4 Storm pistol, which we wrote about on SmallArmsReview.com back in June.

“At the heart of the new APC9 Limited guns is our new fully ambidextrous aluminum lower receiver featuring a highly functional flared magazine well similar in size and shape to our popular jet-funnel accessory, yet formed directly into the receiver,” said Chris Mudgett Vice President of Marketing, B&T USA. “We hit the sweet spot with the 8.9-inch variant with its longer slick forend and MBT stock; this combination makes for an extremely fast-handling, lightweight, ergonomic platform whose fit can be so dialed in, it feels like a natural extension.”

In addition to the new aluminum receiver set, M-LOK accessory slots are positioned at 3-, 6-, and 9-o’clock, an all-new folding telescopic MDT stock assembly with three-position adjustable cheek riser and eight length of pull settings offers the ultimate in functionality and dialed in ergonomics for shooters of all shapes, sizes, and preferences. A pair of QD sling cups adorn either side of the stock, while a rubberized buttstock offers secure, yet comfortable purchase. A flat-faced Elftmann Tactical trigger system rounds out these premium variants of our very popular APC9 that are being offered in finite quantities.

About the APC9 PRO

The APC9 PRO is based upon the United States Army and Air Force adopted APC9K submachine gun and utilizes an innovative hydraulic buffer system to drastically reduce felt recoil and muzzle rise. The platform features functional updates to the original APC series including dual auto-folding, non-reciprocating and ambidextrous charging handles, improved lower receiver ergonomics that include a side positioned bolt hold open/release, removable M4 compatible grip, and Magpul M-Lok accessory slots located on the forend. Like many B&T SMG’s, the APC9 accepts all APC9 PRO lower receiver groups, meaning it can be equipped to accommodate Glock magazines, SIG P320 magazines, or proprietary B&T magazines by simply switching the non-serialized lower receiver group. 

About B&T USA

B&T USA is a Florida-based firearms, suppressor and accessories manufacturer operating under license of B&T AG SWITZERLAND, which was founded in 1991 as a designer and manufacturer of the industry’s most advanced suppressors. Under the leadership of Karl Brügger, B&T AG has evolved into a world leader in the design, manufacture, and sale of the most technologically advanced, high-performance weapons systems in the world. From the comprehensive APC (Advanced Police Carbine) line, recently adopted by the United States Army, to the new 9mm USW (Universal Service Weapon) and USW conversion kits, B&T weapon systems are used globally by police, special forces, and elite military units. For more information on B&T USA, visit: www.bt-usa.com.

Not many shooters will be familiar with the name “Sino Defense Manufacturing”, or SDM for short, at least not outside of Europe. SDM is a market-specific brand under which a major Italian importer – Prima Armi S.r.l., headquartered in a suburb of the city of Turin – distributes a European line of firearms manufactured in the People’s Republic of China by companies such as EMEI (itself part of Chongqing Jianshe Industries Group Co., Ltd.) and others that are mostly part of the NORINCO or China South conglomerates.

The SDM line of products, today, includes numerous semi-automatic variants of the AKM platform in 7.62×39mm and 5.56×45mm, as well as several AR-15 variants; .22 rimfire carbines; handguns – chiefly clones of the SIG Sauer P226; lever-action and pump-action shotguns (including some clones of the Remington 870 design modified to feed from proprietary detachable magazines); and the M77 Commando, a unique semi-automatic bull-pup rifle chambered in 5.56×45mm and based on the QBZ-97b assault carbine with a barrel extended to 14.4 inches in length.

In 2014 and 2015, for a limited amount of time, the SDM line also included the SMG9 semi-automatic short barrel rifle, a civilian version of the CS/LS5 sub-machine gun. Back in the day, the author had a chance to privately purchase one of the very few samples ever imported in Europe. Today, as a satisfied customer, it is still amazing to realize how the SMG9 represents a missed occasion for the importer and for European shooters.

Short barrel rifle or handgun?

It should be specified that while the firearm in question will be addressed as a short barrel rifle for better understanding by the American reader, in Italy – where the author resides – and in Europe in general, the SMG9 is classified as a pistol. Yes, even if it has a stock.

American laws classify any firearm that is originated to be fired from the shoulder as a long gun; on the other side of the Big Pond, a rifle is any firearm that is longer than 23.62 inches (60cm) overall and is equipped with a barrel longer than 11.81 inches (30cm). Anything shorter is considered a pistol. Italian rules on firearm classification specify that, if such a firearm has a folding or collapsible buttstock, the overall length has to be measured with said stock in the folded or fully collapsed position. It is clear that, for the local lawmaker, the chief factor to take into account was not the position the firearm was meant to be fired from, but rather its concealability.

An attempt to regulate – or ban – such a category of firearms Europe-wide was made in 2017 with the 853 European Firearms Directive. Something the European anti-gun crowd really went to town with, and utterly failed. That directive created a new “prohibited firearms” category (more specifically, Category A8) that encompasses “all long guns whose overall length can be reduced under 60 cm through a folding, collapsible, or easily removable buttstock.”

The issue being, the definition of a handgun as any firearm with a barrel shorter than 30 cm, regardless of the presence of a stock, has been established by Annex 1 of the first ever European Firearms Directive (91/477/CEE), and that definition has not been changed. As a result, said restriction remains so far disapplied, and not applicable by the European Commission’s own words dating back to 2018.

As a final legal quirk, the sample hereby pictured for your viewing pleasure is not chambered in 9mm Luger but rather for the quintessentially Italian 9×21 IMI. Also known as 9 Italian, 9×21 IMI was invented in 1980 by Armando Piscetta and first produced by SAMSON (small arms ammunition division of IMI – Israel Military Industries, Ltd., hence the name) as a workaround to the longstanding nominal ban of 9×19mm for the Italian civilian market. Said ban was first eased in 2011, when 9mm Luger was legalized for long guns (pistol-caliber carbines), and then completely lifted for handguns in late 2021. As you read this article, both handguns and long guns in 9mm Luger are finally widely available on the Italian civilian market, although 9×21 IMI is likely to stick around for a while.

A standard design… or not?

First showcased at the 2012 edition of CIPATE expo in Beijing, China, the CS/LS5 submachine gun is a quirky firearm to begin with: originally conceived for internal military and law enforcement use, it found no acceptance in China outside of some provincial Police units, but has been offered for export. Chambered in 9mm Luger, the CS/LS5 was also meant to fire China’s own 9×19mm DAP92-2 high-pressure, armor-piercing cartridge, as well as a variety of less-than-lethal 9mm low-pressure loads with rubber bullets – something largely unheard of elsewhere.

In order to ensure reliability with such a wide variety of loads, the original CS/LS5 submachine gun features a unique gas-assisted blowback operation, where a portion of the gases generated by the combustion of the propellant bleeds from the barrel through a port located in the front sight tower – similar in concept to an AR-15 gas block – and helps the bolt gain rearward momentum regardless of the pressure generated by the round used at a given time. The system is reportedly adjustable to ensure compatibility with sound suppressors.

When converting the design to semi-automatic only for commercial sales, EMEI engineers decided that such a system would be redundant given the pressure range of 9mm loads available on the civilian market. As a result, the gas system adjustability feature has been eliminated, and very little – if any – gas bleeds from what remains of the port on the front sight tower, making the SDM SMG9 essentially a straight blowback, closed bolt semi-automatic short barrel rifle.

The firearm consists of essentially three components: the upper receiver, made out of steel; the lower receiver, made out of synthetics; and the bolt group. With the focus of the CS/LS5 project being essentially export, it was clear that the submachine gun had to integrate some of the most popular features of the best-in-class competitors, and thus both the CS/LS5 and the SMG9 do boast some pretty familiar aspects in terms of ergonomics and controls.

Part AK, part MP5

The most distinguishable feature of the SDM SMG9 short barrel rifle is the MP5-type cocking handle located over the barrel, with its manual hold-open cut. The charging handle is non-reciprocating and secured to a tubular piece of metal that runs within the top portion of the black polymer handguard. It can be locked forward but is not easily removable and not reversible for left-handed users. Both halves of the handguard can be removed by extracting a captive front pin from underneath the upper receiver. A set of short Picatinny rail segments are secured to the lower portion of the handguard at 3, 6, and 9 o’clock positions, and can be removed at will with a hex key.

The upper receiver is a single piece of blued steel and is strikingly similar to that of the Chilean FAMAE SAF submachine gun; the barrel is firmly secured at the front, and a MIL-STD 1913 Picatinny rail for optics is integrally machined on top. The upper also includes the front sight tower – a hooded post adjustable for elevation – and the adjustable peep-hole rear sight. Also integral to the upper receiver is a fixed extractor.

The bolt of the SDM SMG9 comes straight from planet AK. All it takes is a glance to find the similarities between it and the bolt groups of Russian 9mm SMGs of AKM descent, such as the PP-19 “Bizon” or “Vityaz”, albeit extremely simplified, with no side charging handle. The return spring is captive to its guide rod and seated right behind the bolt; given the architecture of the SDM SMG9, the rear dust cover latch typical of AK designs is nowhere to be seen here. Since the adjustable gas system of the CS/LS5 sub-machine gun has been removed from the SMG9, the front tube – where the gas piston on the AK would be – here exists only to give leverage to the charging handle to push the bolt rearwards.

The lower receiver is a solid plastic component that hosts the trigger group – visibly, a scaled-down version of the AK trigger – and basically all other controls. A two-position safety is located above the grip on the left side, at easy thumb reach. The safety blocks both the trigger and the charging handle, meaning the bolt can’t be manually cycled when the safety is engaged.

The grip is integral to the lower receiver and has storage space accessible from a sliding door at the bottom for tools or spare batteries. Two magazine release catches are provided; a paddle release on the right side, and a button-type release on the left. Both are easily accessible by the user’s thumb or index and can be operated with the right or left hand alike.

The SDM SMG9 feeds from a curved, double-stack polymer magazine, whose only metal component is the follower spring. The magazine normally holds 30 rounds, but versions riveted to hold only 15 rounds were made available for those European jurisdictions with magazine capacity restrictions at the time.

The magazine is probably the weak link in the gun: as reliable as it has proved to be, it also tends to crack at the feed lips and become unusable if dropped when full. Just like in the Heckler & Koch MP5, there is no last round hold-open capability. The magazine is proprietary, but compatibility with other magazines (e.g. MP5), albeit with modifications, could be explored.

The stock of the SDM SMG9 is hinged to the lower receiver by a metal plate and held in position by a spring-loaded button catch, meaning that the release button must be pushed to both fold and extend it; it folds to the right side, and doesn’t interfere with the ejection port or the controls when folded. The metal plate also integrates the rear sling loop; a second loop is located on the front sight tower. Both are on the left side only.

Great on target, a missed occasion

With its no-frills, no-nonsense, extremely simple working system and architecture – all it takes to fieldstrip it is the removal of a captive pin – and its 8.5-inch barrel with a conventional rifling, the SDM SMG9 is also extremely accurate for a gun of this make and category. It is by no means impossible to dump an entire magazine into the center ring of an ISSF 25m target. The SDM SMG9 is lightweight, it’s comfortable to shoot, the polymer folding stock provides a very good support, and when the trigger is pulled, the SMG9 will just work. Every. Single. Time.

Unfortunately, the importer didn’t seem to believe in the potential of the design as a competitor to more highly regarded, highly priced designs such as the CZ Scorpion EVO, the MP5, and other popular civilian-grade short-barrel rifles. The grand total of SMG9s ever imported in Europe doesn’t exceed twenty units, with maybe five sold in Italy, where now they rake up to 2000 Euros and up on the used guns market.

That’s a crying shame, because the SDM SMG9 had a lot going for it, even with the downsides of its proprietary magazine. The legal classification as a handgun opened a pretty wide and receptive market for it, even in Europe. And since, in most of Europe, private security personnel not only have to buy their own guns, but often resort to this kind of SBRs for cash-in-transit, the price point – which, back in the day, was almost half that of a CZ Scorpion EVO, and literally planets away from that of a B&T APC, or an MP5 clone – could have made it a winner.

As of today, the author wholeheartedly sticks to his SMG9 for training, leisure shooting, and home defense. Those who overlooked it back in the day, frankly, don’t know what they’re missing.

Specifications

Uzi!…. For years the mere utterance of the word has sent the heart pounding and the pulse racing in the minds of soldiers, Hollywood producers, and homegrown Walter Mitty types alike. This near mythical creation out of the brilliant mind of Uziel Gal (Galilei) has risen from the depths of despair of a nearly stillborn young nation, to its current status as THE defining image of at least three generations. There is almost no place on earth that the name, or image, of the Uzi Submachine gun cannot be found such that this universal familiarity has led to its being one of the most popular firearms on the collectors market today.

Available Guns

Unfortunately for the NFA weapons collector in these United States, the Uzi SMG is not as readily available as its worldwide status would suggest. Due to our controlling firearms laws and the market demands of past years, the collectible versions of the Uzi have come to be defined by three distinct variations.

Any fully transferable factory produced, foreign made gun (SMG) would have to have been imported prior to 1968 and the enactment of the Gun Control Act. In this category there exist two variations of the type: the Israeli/IMI produced originals, and the license built clones produced in Belgium by FN-Herstal. But before you start looking for one of those be aware that very few of either origin were ever imported prior to 1968 and they command a premium price!

The only other option for a Factory produced SMG is either the large number of dealer sample/law enforcement guns that were imported between 1968-1986 (which are restricted to acquisition by civilians who are Special Occupational Tax Payers only), or the US manufactured SMGs produced in the middle 1980s by Group Industries Inc. of Louisville, Ky. The Group guns are factory produced SMGs, accurate and exact in every detail, as they were manufactured on jigs and tooling obtained from FN, often using original FN produced parts obtained in the deal. They are also all fully transferable. Group guns are available for approximately less than half the cost of a Pre-68, fully-transferable, foreign produced, original gun and they are just as good as the originals. The differences are in finish only, and as a bonus the Group guns were offered from the factory in .45ACP and .22LR calibers, in addition to the standard 9mm caliber. It has been reported that very few of the non-9mm calibers were delivered from the factory as such. Group also sold caliber conversion kits as an accessory item. There have been a few problems with later Group Industries Uzis, mostly related to the bolts. Installing a factory Uzi bolt seems to alleviate the problems.

The last, and most common, version of the NFA collectible Uzi SMG are those guns that originated as Title I semi-auto carbines, and were later converted to select fire and registered with the NFA (National Firearms Act Branch of BATF) as transferable SMGs. These guns come in two distinct flavors. First is the “registered receiver conversion”, whose registration status allows the receiver to be modified to the factory original SMG configuration. The second is the “registered bolt conversion”, which employs as the registered item a special bolt that has been manufactured to fit and function in the receiver of a standard, unmodified, semi-auto carbine but in the select fire, open bolt, mode of operation. This type of conversion cannot legally employ some of the standard SMG features that would require receiver modifications, as discussed below.

These two types of conversion guns are our topic of investigation, as there are many variations. As with all conversions, there exist guns that were converted correctly and safely, and there are those that bear watching out for. A thorough understanding of the accepted practices used in a proper conversion of each type will allow the prospective buyer or current owner to gain maximum enjoyment from this gun, while avoiding a potentially bad experience.

The Semi-Auto Carbine

It must be first understood that Action Arms Inc., over the course of the years they were importing the semi-auto guns, imported two different versions the Uzi semi-auto carbine. These versions were officially known as the Model A and the Model B, and they were essentially identical mechanically, except for certain small differences, some of which were also being incorporated into the factory SMGs at this time too. The most noticeable difference was the arrangement of their sighting systems. On the Model A the sights are identical to the original SMG design, in which all adjustability for windage and elevation is accomplished by movement of the front sight elements. The rear sight is a fixed peep, adjustable only for two range settings of 50m and 100m. Part of the problem was not taking into account the change from a 10 inch barrel on the SMG, to the 16 inch barrel on the semi-auto. The Model B incorporated a new sighting system which allowed elevation adjustments on the front sight post, and windage from the rear sight peep, in addition to the range selections. The operational difference is that the Model B does not require any special tool to make adjustments, whereas the Model A requires a dedicated sight tool. Also, on the Model B, the front sling swivel rotates a full 360 degrees, while on the Model A it cannot rotate through a full arc. On early versions of the Model A the bolt face was also slightly different. Early imports had a full cartridge seating bottom rim, whereas later Model A (and all Model B guns) incorporate a relieved lower cartridge seat face to hinder easy conversion to full-auto fire. This became an important distinction when legally converting these guns, as discussed below. There is a perception that the Model A was a better candidate for conversions, as it was closer to the original SMG and could be converted more easily, in some cases. On a few of the very early examples of the Model A, the blocking rail was not adequately welded, which may be the root of that bit of MG Lore.

As an aside it must be pointed out, that while all Israeli manufactured semi-auto carbines were imported by Action Arms Inc., there was also a clone of the semi-auto carbine made by Group Industries here in the USA Group Industries started making SMGs and when the 1986 making ban occurred, they tooled up for the semi-auto guns, of which there are a small number about, but nowhere near as many as of the Action Arms imports. And though it has never been reported that the Group semis were available in time to be receiver registered, as transferable SMG conversions prior to the 1986 making ban, many have apparently been used as the host guns when installing NFA registered, conversion bolts. The design and quality of Group Industries guns rivals that of the Israeli originals, and there should be no hesitation in their employment as host guns for bolt conversions. For our purposes here we are only concerned with original Israeli-made guns, and possibly these Group Industries clones when used as the basis for a conversion with a Registered Bolt. It should be noted that there were imported at differing times, and by differing importers, unlicensed, cheap copies of the semi-auto carbine made by Norinco in China. These poor quality guns made it in under the name of “Officers’ 9”, long before the semi-auto import ban, and long before the ‘current’ rash of Norinco Uzi Carbine clones, imported as sporter rifles commonly seen with thumbhole, sporter style fixed stocks. Despite when (and under which name) these Chinese copies are encountered, it must be very clearly stated that they are extremely poor copies, with regard to metallurgy, fit, and finish. They are so poor as to preclude discussion here. Due to the timing involved, very few of the Chinese guns would seem to have been in-country and able to be registered prior to the 1986 making ban, but some may have been used for an SMG conversion with one of the many legally registered conversion bolts. Under no circumstances could this be recommended, as these guns are so poorly made as to be potentially impossible to make them function reliably with a conversion bolt installed.

What’s So Different About a Semi-auto Carbine?

Like other semi-auto derivatives of ex-military pattern machine-guns, the Uzi semi-auto carbine had to undergo a significant redesign from the SMG parent in order to pass the BATF’s measuring stick to allow importation and sale to U.S. citizens as a Title I firearm. Obviously, such changes are made with the intention of NOT allowing an easy conversion into a machine gun, and it is important to fully understand these engineering changes. A proper, safe, and legal conversion will have retained the inherent safety features of the parent SMG design, while rendering as close as mechanically possible a virtual copy of the SMG functionally and aesthetically. Israel Military Industries (IMI), unfortunately for the NFA collector community, went far beyond the absolute minimum changes required from the SMG design to allow importation and sale in this country. These extra semi-auto only features are the central focus of most of the complaints leveled at conversions of these guns, with regard to function and user-friendliness.

The differences between a functional conversion (one that merely duplicates functionally, full-auto only, or selective fire), and a complete conversion (one that virtually replicates the original SMG in all aspects including function, parts interchangeability, and appearance), are significant. They can cause extreme variation in the fair price range of differing guns. To gain a complete understanding of the selection and desirability of available guns out there, let’s first take a look at the basic mechanical differences between the SMG and the semi-auto carbine (as originally imported).

The single most important difference between the original SMG and the semi-auto carbine is in the respective methods of operation. The SMG fires from the open-bolt position using a fixed firing pin. The carbine had to be redesigned to fire from the closed-bolt position, utilizing a striker. This was solely to pass importation restrictions based upon a pending ruling prohibiting the manufacture of semi-auto Title I guns that fired from an open bolt. To this end there were several significant design changes made. The first was the installation on the rear upper right side of the sheet metal receiver of a long piece of rectangular shaped metal bar (known as a ‘blocking rail) that prevented the drop-in installation of the SMG type, fixed firing pin, Open Bolt. In order to accommodate the blocking rail inside the receiver the semi-auto bolt has a full -length notch cut in its upper right side to allow passage over the blocking rail. Since the gun could not use a fixed firing pin a striker mechanism was incorporated into the bolt group, which now comprised a slightly shorter Bolt with a full length hole drilled through its center to accommodate a moving firing pin, this pin came forward upon, sear release, to strike the cartridge primer. The bolt itself now merely reciprocated within the length of the receiver housing, with each shot closing upon the freshly chambered round. The the striker assembly stayed caught by the sear in the same rear position of the former SMG open bolt. The striker assembly itself comprised the long firing pin and square section of steel that had a sear holding notch cut into its bottom surface, along with a separate spring to provide the striking energy. The semi-auto now had two separate spring assemblies; the main recoil spring (attached in the familiar place on the bolt itself), and the smaller striker spring. There is an interconnecting slot cut into the left side bottom of the semi-auto bolt to mate with the long arm of the striker assembly. This assures proper alignment during movement. Due to the fact that the striker arm (contained the single sear notch) the right bottom ridge of the semi-auto bolt that would normally contain a sear notch in the SMG bolt is milled open from the rear of the ejection opening, to slightly ahead of it. The SMG bolt is solid on the top and side faces, except for the sear holding notch, and the ejection port opening. To finish out the bolt group changes, the SMG has a different type of extractor than the semi-auto bolt. The lip of the semi-auto extractor is considerably thinner and shallower than that installed on the SMG bolt, for unknown reasons. It is clearly desirable to have the SMG version installed in a full-auto gun, and probably any version of the gun. They are completely interchangeable. Lastly, a note is in order on the two different kinds of semi-auto bolts that were installed on the Model A guns, as this has an important bearing on how these guns may have been converted to the full-auto fire mode. When IMI first designed the Model A semi-auto bolt the bolt face was identical to the SMG open-bolt design (save for the deletion of the fixed-firing pin) in that it incorporated a full-circumference cartridge holding rim. This cartridge holding rim was designed to snap around the base rim of the cartridge and hold it in position as it entered the chamber, just prior to contact with the fixed firing pin. Later Model A, and all Model B, guns have the lower section of this rim machined off, as another disabling design feature, to preclude easy modification to full-auto fire, as will now be discussed below.

Now, with the mode of fire changed, the fire controls had to be similarly altered. All fire-control parts are contained in a separate housing attached centrally below the receiver of the gun, and which also comprises the pistol grip and the magazine well. The SMG fire-control assembly allows for three control positions, safe, semi-auto, and full-auto. The selector levers have a small right angle, finger-like, bent piece of metal which, in a SMG installation, moves forward and bypasses the disconnector function in the fully forward full-auto position. For semi-auto fire to occur it is placed in the middle position, where it can function the disconnector, releasing the sear after the trigger nose drops. To force the condition of semi-auto only operation, whereby the disconnector is activated continuously, it would be required to mechanically preclude the selector from moving forward past this point. The alterations were made to the semi-auto grip housing by adding a small block of metal inside the front center shelf of this housing to preclude the selector lever from moving forward enough to engage the full-auto position on the trigger nose, and by-pass the disconnector. The selector levers themselves are the same except for deletion of the third select position notch. Very early semi-auto selectors were identical to the SMG versions, and had all three control position notches already cut. Later versions deleted the third position. Concurrent with the changes in the semi-auto guns which resulted in their being redesignated as Model B, all versions of Uzi selector levers had a vertical safety tang added to the upper surface of the lever, which prevented the sear from dropping (by blocking the left underside sear finger, in the same mechanical fashion as the right underside finger is blocked by the vertical tang of the grip safety) until the selector switch was moved into one of the Fire positions.

The only other difference in the fire-control parts relates to the sear itself. The SMG sear is quite noticeably larger on the fingers that protrude up into the receiver to catch the bolt. In comparison, the semi sear, because it only had to restrain the much lighter striker mass, has smaller fingers. The smaller semi sear will work but is NOT recommended, as excessive wear can result. A proper conversion will have the sear projection holes in the bottom of the receiver milled out to the correct dimensions to allow the factory SMG sear to be installed and function. This was not always done, and on conversion guns utilizing a Registered Bolt it may be looked upon as an illegal receiver modification by BATF, unless the bolt was permanently married to the receiver by serial number on the transfer form. (A note on all Uzi sears: the sears, by design, are made to a less hardened surface treatment than the bolt so that when wear does occur, and it will, the comparatively cheaper sear can be replaced rather than the entire expensive bolt. A highly worn sear can allow runaway fire, in slips over the rounded, worn, sear fingers so always check the sear condition on regular basis!)

Lastly, on the fire control group, the axis pins that hold the lower receiver control group onto the upper receiver have two different size mounting pins/holes, again to preclude a direct swapping of the SMG group onto the Semi-auto receiver. The SMG uses a 5mm pins and receiver holes, while the semi-auto guns use 7mm pins and receiver holes. This prevents an SMG lower from being pinned on without enlarging the pinholes in the SMG trigger housing. You will still have to use 7mm pins to mount it. With the availability of parts kit guns now so abundant many people have chosen to install a real SMG lower, either for increased reliability, or just to get the Hebrew markings of the Israeli originals.

Jumping back up into the front of the receiver, we discover yet another joyous collection of maddening alterations that hinder our journey back to the world of the original SMG configuration. The two most often heard complaints about owning a conversion SMG relate to the barrel selection availability and mounting problems. IMI thoughtfully left no stone unturned when redesigning the Uzi for semi-auto sale in the U.S. Their most fondly remembered alterations prevent the installation and usage of cheap and plentiful SMG short barrels, instead forcing the owner of an SMG conversion that has not been fully SMG configured to resort to modifying and cutting down semi-auto barrels. Thankfully there are on the aftermarket barrels that will interchange. (It should be noted that possession of one of these short barrels that will drop into a semi-auto Uzi and the semi-auto Uzi itself would comprise possession of a short barreled rifle, requiring registration under Title II of the 1968 Gun Control Act). The semi-auto is different from the SMG as regards barrel mounting in two important aspects. First, the actual barrel trunnion, which forms the heart of the forward part of the upper receiver by being welded into place, has a smaller diameter passage hole for the barrel flanges than on the SMG. This prevents an SMG barrel from being slipped into the trunnion. On the front of the magazine well, inside the bottom of the receiver, is welded on both SMG and semi-auto versions a cartridge feed ramp to guide the nose of the bullet into the chamber of the barrel. On the original SMG version that is all that it is, a cartridge guide. On the semi-auto version it also contains a thick ring which serves to hold the rear end of the barrel in position on the feed ramp, but more importantly it prevents the larger rear diameter of a standard SMG barrel from being inserted and utilized in the semi-auto guns. By virtue of the SMG barrel flanges being of a larger diameter, they cannot be directly inserted and used in a semi-auto conversion that does not have these two features fixed. So one has to either cut and recrown the semi-auto barrels, or turn down the flanges on the SMG versions. A proper and complete conversion will have had the trunnion passage hole bored out to SMG spec, and the barrel ring milled off the feed ramp.

The last important difference between the SMG and the semi-auto carbine is in the design of the top covers. The SMG cover has an extra mechanism in the cocking track designed to prevent inadvertent discharge of the weapon if the cocking knob is accidentally released prior to full rearward travel being reached and sear lock-up of the bolt. This is commonly called a ratcheting top cover, due to the small ratchet mechanism which will catch and hold the bolt. This is only a feature in the open- bolt guns. It is not found, or needed, in a closed bolt firing weapon. The visible tip off to identification is the row of ratchet teeth along the side of the top cover bottom track. Semi-auto tracks are smooth for their entire length. There is also a slight difference in the length of the cut opening between the SMG and semi-auto carbine top cover tracks, which will be explained below. A proper conversion need not have this ratcheting top cover to function correctly, but anything designed, and available to the owner/operator, for safety reasons should be utilized. It is not possible to modify the semi-auto top cover for this ratcheting mechanism (for all practical purposes at least), so most complete conversions will have this entire assembly exchanged for a standard SMG unit. The other bonus benefit to this exchange of top covers is that the semi-auto carbine has a lengthy and annoying warning against illegal conversions stamped into the cocking knob slide, and since we’re discussing a legal NFA registered weapon, it’s only fitting to eliminate such aggravating visible verbage on the exterior of the weapon. (See Photo on page 73.)

There is one more aesthetic difference between the semi-auto carbine and the SMG. Both guns could utilize either a folding metal stock or a fixed wooden one. The folders attach semi-permanently in the same fashion on either gun, but on the SMG the wooden stock is provisioned for quick detachment by a release lever on the stock underside. On the semi-auto carbine, the wooden stock is semi-permanently attached. The SMG quick-detach wooden stock will interchange for those who so desire.

The Three Conversion Methods

Now, with an understanding of the various mechanical differences between the SMG and the semi-auto carbine, it is relevant to discuss the actual mechanical methods of conversion that will be found on a NFA registered Uzi carbine SMG conversion.

It did not take long after Action Arms Inc. began importing the first carbines to the USA in 1980. Before some very industrious minds began to figure out how to convert the gun into a full-auto firing (versions in full-auto only, and selective full-auto fire) submachine gun.

The first type of conversion took clever advantage of the design of the striker-fired, closed-bolt, semi-auto mechanism in spite of all that IMI had done to prevent easy conversion. In fact, some of the IMI changes actually facilitated this type of conversion! Recall from above, that the first Model A guns to come in were slightly different than all those that followed. IMI had forgotten a few very important details it seems! For the open-bolt mode of fire, the full-circumference rim on the bolt face, designed to guide the cartridge into the chamber prior to the fixed firing pin striking the primer cap, is critical. Without this lower rim on the bolt face the cartridge bottom rim will hang up on the firing pin, causing jamming as it enters the chamber. The cartridge rim will climb into the bolt face too soon. On a closed-bolt weapon there is no firing pin in the way, until sear release of the striker after bolt closure and chambering, so the elimination of that lower lip is of no consequence unless somehow, that fixed firing pin, or its equivalent, suddenly reappeares! That is exactly what those industrious minds figured out how to do. If the striker could be attached to the rear of the bolt it would act as an open bolt, with a fixed firing pin protruding at the bolt face. Even simpler, it was noticed that the striker spring was strong enough to carry the striker in place against the rear of the bolt during chambering, enough to cause reliable primer ignition! Now you were half way there. The earliest Model A bolts had the full-circumference cartridge holding rim already, remember? Two thirds of the way there. If you could somehow allow the selector lever (early Model A select levers had three detent notches) to move forward far enough to interrupt the disconnector function, the bolt would continue to reciprocate until trigger release…. full-auto (only)! Method one done.

In finer detail, these were mostly all registered receiver conversions for two basic reasons. Reason one, because at this time there was no economic reason NOT to register the whole gun as an SMG, and reason two, the ATF rulings which brought about the so-called “machine gun conversion parts” distinction was just beginning to get started with the “AR15 drop-in auto sear” mania and the like, with the Uzi conversion scene adding to the fire for the following reason. From the just discussed conversion method above, it becomes apparent that one could convert a semi-auto carbine to full-auto with no receiver modifications. If a new selector lever that bypassed the disconnector function could be made that could drop-in, and replace the semi-auto one directly. That was exactly what was done in some cases, with a “Conversion Selector Lever” being NFA registered as the machine gun itself, and either installed in a gun by a Class II Manufacturer or owner (on Form 1), or sold by itself. ATF promptly ruled this lever was a machine gun with the usual warning against unregistered possession, etc.

So, early Model As (with the full SMG style lower bolt face rim) can be found with this NFA registered lever as the only difference, but they will be able to fire full-auto only, not selectively. For later bolts with the lower rim machined off, it was necessary to reinstall that rim as in an SMG bolt face. This was usually done by welding a machine contoured ‘half rim ring’ back onto the bolt face itself. For the selector lever itself to NOT be considered a registerable part under the NFA, it had to be of the original design with the right-angle finger attached that engaged the disconnector (and blocking piece welded onto the front lower shelf of the trigger grip frame housing). Early Model A select levers with all three detent positions could be used just as a regular SMG part if the blocking piece could be removed, but doing so altered the ‘as manufactured’ status of the gun, and was disallowed by ATF, unless the receiver was NFA registered, and this was the only way to remain legal with a conversion of this type early on. The proper conversion method then had the blocking piece removed to replicate the SMG control housing function. Later semi-auto select levers were devoid of the third detent notch, so that had it to be reconfigured on later guns undergoing conversion. This describes the various NFA registered guns that can be encountered from the earliest conversions done. This phase lasted only about a year or so, and changed very quickly when those industrious minds went to work again, this time on the bolt itself.

Since to modify the relieved bolt face seen on most Model A guns required accurate welding and reheat treating of the bolt, it seemed easier to start with a bolt already manufactured in the full SMG configuration as regards open bolt firing requirements. If you started with a SMG type bolt the only major modification needed would be to allow placement inside the semi receiver with its blocking rail. A simple job of milling a slot in the correct location to mimic the design of the semi-auto bolt, and the gun would function in the open bolt mode. And so the now famous “slotted bolt” was born. The first versions sold openly were designed to accommodate the normal closed bolt recoil spring and buffer arrangement which was slightly longer in depth on the semi gun because the semi closed bolt did not need to reciprocate as far back into the receiver because of the striker assembly riding behind it. To this end, the cut track opening for the cocking slide in the top cover had a slightly shorter track, as the cocking slide did not need to be drawn as far back with the striker engaging the sear instead of the bolt. To retain as much of the original SMG operating characteristics as possible, it was soon seen that by replacing the semi recoil and buffer assemblies with a standard SMG version the slotted bolt could attain all the relevant dimensions of the SMG, save for the milled slot in the side. By increasing the length of the slotted conversion bolt to normal SMG spec it also restored the normal cyclic rate by virtue of the increased mass and recoil travel. The only down side to this bolt, and all future NFA registered conversion bolts of this description, is that it now required the full travel of the cocking slide to engage the bolt notch with the sear while cocking the weapon, such that it became necessary to now mill open the length of the cocking track opening to normal SMG specs too. It was often easier to just replace the whole top cover, with the added benefit of the SMG ratcheting mechanism coming along for free.

This all came to an immediate halt in mid 1982, when ATF ruled that such fixed firing pin, slotted bolts, like the drop-in selector or lever, were machine guns in and of themselves, so future manufacture, sale, and possession was to be in full compliance with the NFA. There were though a small number of legal registered receiver conversions made by using these unrestricted, restricted, conversion bolts prior to that ruling, and they were allowed (grandfathered), as they were previously lawfully, registered in full compliance with the existing laws, though the conversion bolt now needed to be married to that particular serially numbered receiver. If it ever needed replacement you were out of luck. With this restriction some of these registered receiver guns simply ditched (read: destroyed) the UN-registered conversion bolt and went ahead and finished the receiver modifications that allowed utilization of an original, solid SMG open-bolt, as these were the only bolts that remained legal for unrestricted sale and transfer after the ruling.

This is the basis then for the second most common method of conversion, that of using an NFA registered, slotted conversion bolt, in an otherwise unmodified Title 1 semi-auto receiver. These slotted conversion bolts were still made and marketed, but they now had to be individually NFA registered, and a lot of them were! The slotted conversion bolt” is operationally identical to the standard SMG open bolt, except for the milled slot in the right upper side face. All other relevant dimensions and operating characteristics are the same, with one small nod to the inescapable reality that it was to be used in an unmodified semi-auto carbine receiver. All semi-auto carbines incorporate the barrel modifications as described above such that a normal SMG bolt face, if used in an unmodified semi-auto receiver, would not properly close against the rear of the barrel chamber, as the restrictor ring which surrounds the rear of the semi-auto barrel would interfere. So, NFA registered slotted conversion bolts are slightly relieved at the forward upper bolt face to accommodate the normal semi-auto barrel and mounting setup.

With a registered conversion bolt installed, it was deemed acceptable by ATF to allow modification of the lower receiver trigger housing fire control unit any way desired, and most units were simply modified from the semi-auto to selective mode of fire, as described above. It is also perfectly acceptable to swap out the semi-auto unit for a standard factory original SMG lower, as long as the SMG trigger housing is modified (by opening up the mounting pin holes to 7mm), and not the upper receiver center block! Even with a registered slotted conversion bolt installed, upper receiver modifications are generally disapproved of by ATF, although the only specifically illegal modification is removal of the blocking rail on the right upper inside of the receiver. The caveat against modifying the lower receiver push pin mounting hole to bring it back to the 5mm SMG standard is that it may be viewed as evidence of intent to illegally convert the semi-auto upper receiver (by allowing pin-on conversion of an SMG lower housing combined with the first bolt modification method described above) if the NFA-registered bolt is ever separated. It is inadvisable to make this modification in light of that distinction. Guns found with the remaining upper receiver modifications, such as barrel trunnion and feed ramp alterations, are not illegal and add to the perceptible value of the gun if done in a professional manner. An SMG conversion using a NFA-registered slotted conversion, bolt is an excellent method of conversion as it does not overly hinder one in obtaining a near copy of the factory SMG original, and in most cases the absolute differences between a bolt gun and registered receiver conversion are merely aesthetic, with the spare parts scenario being the most common complaint. And, if you already have a semi-auto gun in your collection, the acquisition of an NFA-registered conversion bolt may allow an inexpensive changeover into the full-auto realm of the design, as it was originally intended.

The only remaining point to discuss about these registered conversion bolts is as regards their inherent value and weaknesses. All of these bolts were NOT created equal, either in materials or workmanship! If it is decided that a conversion bolt is the way to proceed a careful examination of the intended bolt is in order if you wish to maximize the usage and enjoyment of the converted gun. slotted conversion bolts were made from two distinct sources, each with its own pluses and minuses. The first and most obvious source was to simply take a factory original SMG open-bolt, and then make the two modifications to adapt it to conversion use in the semi-auto carbine, namely milling the clearance slot, and the bolt face relief cut for the rear barrel support ring. The main concern here is: Did the manufacturer of these bolts properly account for the re-heat treatment of the finished bolt. Since these bolts are normally hardened, it should have been annealed prior to machining, and then heat treated again to proper finish hardness. A finish hardness of at least Rockwell 55-56 on the C (hard, but able to be cut with a file) scale is desired to prevent premature wear of the sear holding notches and bolt face. A tungsten carbide-cutter mill may have been used instead of the heat treatment process (es), but this could lead to localized heat distortion damage (unlikely) during the milling operation(s) if it is not done very carefully. Closely examine any bolts that show evidence of stress risers, hairline cracks, crystallization or burring.

The second method involved new manufacture of slotted bolts, either from machined forgings, bar stock or investment castings. Both forgings and bar stock are common, and perfectly acceptable as base materials for a machine gun bolt, with a slight nod being given to the forged bolts as they duplicate the factory original manufacturing method, while having intrinsically better metallurgical properties. Lastly, some new manufacture bolts were made from cast steel and then finish machined. Investment cast parts are acceptable, providing that the proper manufacturing methods were employed during casting, and were to industry standards. The single most common problem found with cast parts relates to improper cooling practices which allow finished dimensions to stray from spec. All cast Uzi bolts were not created equal, and there are unfortunately cast Uzi bolts that are known to be off-spec due to a materials specification change which substituted a different alloy than originally specified. This material had a slightly different contraction rate, which caused it to cool to a finish dimension that was larger than tolerance. There ended up being a small lot of these poorly cast slotted SMG bolts NFA registered, and they are quite obvious by the fitting marks that were required to get them to function.

All of these bolts of any manufacturing method, should be heat treated for long-term service, so check the pedigree of the bolt in question and verify manufacturing specs if at all possible. As regards reported, known problems with these registered slotted bolts, it boils down to two areas. First, for the reasons above, some bolts exhibit an excessive wear profile in the sear holding notches which can lead to eventual failure to properly hold on the sear fingers. Potential dangers from run-away firing aside, this is not that serious of a problem to repair, though it entails welding up the sear notches in a jig and then re-machining them to spec (followed by proper re-heat treatment!). Secondly, some of the improperly heat treated bolts have had their fixed firing pin wear down from extended use to the point where there is not enough pin protruding to reliably cause primer ignition. The only acceptable method of repair here is to bore out the old pin and install a replacement fixed pin which can be heat-shrunk into place. These repair pins are rare items, and few people working around MG’s have any experience with doing this, but since we are talking about a registered part, repair is the only legal way to go registered slotted bolts should, of and in themselves, be of no particular concern as regards wear and longevity in an SMG conversion, as they have the full potential to meet a normal factory original parts life and utility span, if they were correctly manufactured in the first place. As with all conversion parts though, once the general design was in the public domain many different sources made and registered them and all were not created equal, so a close physical examination is advised. And if a well-worn, or even damaged or improperly manufactured, registered bolt should be found, do not discount it out of hand, as it can be repaired and restored to operational status by a competent professional. The price to be paid should reflect the overall condition, but with registered NFA items getting more valuable with time, any item with a registration paper/tax stamp is worth a close examination prior to purchase, if at possible.

“As a general rule, ANY bolt gun is worth less than a registered receiver conversion of comparable condition.”

The final conversion type is the so-called registered receiver gun. As most people understand the meaning of the term, it is qualified by one underlying distinction, the removal of the blocking rail inside the receiver to allow utilization of a standard, solid, SMG open bolt. Though we noted that there are a select few registered receiver guns, as described above, that were converted by other methods, these are not generally perceived to be of the same general class, as they still have the blocking rail intact and therefore have not been converted to SMG description. However, due to their receiver status they most certainly could be completed to full SMG spec at the owner’s discretion. The owner who wishes to do so should check with ATF Technology Branch first before doing so – and get it in writing. But for most registered receiver guns, their attraction lies in the fact that they can be fully converted to a near clone of the factory SMG, in both function and appearance. Due to the registration status, with no legal barriers to altering the receiver itself, we are free to return the receiver to its normal SMG description.

This complete conversion of the gun back to its near factory SMG description is accomplished as follows, though individual guns may exhibit various stages of completeness of the full conversion. The complete conversion is begun by removal of the bolt blocking rail in preparation for installation of a factory original SMG open bolt. The IMI design for the mounting of the blocking rail incorporated two extension tabs near each end, that located the rail by mating with opposite slots in the receiver sidewall, and then were welded in place and had the welds ground smooth prior to finishing of the weapon’s exterior. When altering the receiver for the conversion to a factory type SMG bolt it became necessary to remove the rail completely, flush with the receiver sidewall, a job best accomplished with a vertical milling cut, as the mill could be controlled to safely remove the rail flush with the receiver sidewall without causing damage. The problem with this is that the last section of the rail was installed too far back in the receiver channel to allow milling it completely free, so some ingenuity was called for. Most conversions were done by carefully milling off the rail as much as possible rearward then using a small torquing force, or shear force, to break free the remaining tab joint. Done carefully, this resulted in no damage to the receiver sidewalls, though many people apparently used alternate methods than a mill, or rushed the job or applied too much torque/shear force as twisted/dented rear sidewalls are one of the most common flaws in conversions. These sidewall flaws can be straightened, but it is a difficult job and best done by an experienced professional.

The other required major alteration to the semi-auto upper receiver, to render it a clone of the factory produced SMG, was the conversion of the barrel mounting points. The barrel trunnion through-hole needs to be opened up to the SMG factory spec diameter, and properly converted guns will have had this done by line boring to the axis though more commonly this was simply placed into a vertical holding fixture and a drill press was used. This can result in misalignment of the mounted barrel and may be a root cause of feeding troubles, and failure to be able to properly tighten the barrel mounting collar. The rear barrel holding ring/feed ramp assembly will also have to have the entire ring structure milled off flush with the upper surface of the feed ramp, duplicating the SMG ramp contours, to avoid bolt face contact. Once these two operations were performed, an SMG barrel could be simply replaced.

The selector lever block in the top inside shelf of the trigger housing frame was also installed by the same locating tab method, as employed on the blocking rail in the upper receiver. The correct method to remove it was a simple milling operation, though other torquing/shearing operations were commonly utilized. If the block was not fully removed flush, or if any remnants of the weld are left, there may be interference with the elongated right-angle finger of the selector lever that prevents smooth operation of the disconnector function and subsequent improper semi-auto functioning. So, to do a proper conversion, one must completely remove the select lever block, as some improper conversions merely attempted to notch, or cut out, instead of fully removing the block, and a sticking or troublesome selector lever can usually be traced to this. An SMG selector lever is the ideal way to complete a fully correct conversion, and this can be simply exchanged, although the majority of conversions probably used modified semi levers (note: there are two different SMG selectors available – later production ones have the safety tang, early military ones do not.). The semi-auto select levers were modified by adding the third detent, and these detents may give trouble if not properly done. Check for correct depth and spacing as compared to the original two semi-auto only control positions if the selector will not engage the full-auto position smoothly and firmly. A correct job will have the third detent milled, as the factory did, and not hand cut or ground out.

As discussed above the remaining operation to the trigger housing was remarking of the housing exterior for the third selector detent position after it had been milled, cut, or stamped into the housing exterior. The exterior of the trigger housing is where it is easy to tell the care and professionalism, or lack thereof, that went into the conversion. The remarking of the housing for the third detent position can vary from either indistinguishable from factory, to sloppy and badly mismatched. A cold chisel and hand stamp, held by hand and eyeballed, was often the preferred method. The best conversions will have utilized a professional stamping fixture with a font-matching stamp to duplicate the lettering already existing in the other two positions, combined with welding up of the old fire position F, and restamping of the now required R for the semi-auto detent position. Some conversions may simply have had the entire semi-auto unit replaced with a surplus factory SMG type trigger housing, which should be unaltered except for the required modification to the mounting pin holes of the SMG trigger housing. If the original semi-auto sear was exchanged for an SMG sear, with the full width fingers, the sear clearance holes in the bottom of the upper receiver will need to be enlarged to SMG spec for proper clearance. The difference is slight, and many were not properly enlarged as required. For reliable operation with the SMG sear it is necessary to enlarge the holes.

“..Group Industries guns were offered from the factory in .45ACP and .22LR calibers in addition to the standard 9mm..”

The top cover modifications, required for the SMG open bolt installation as discussed above, will most likely have been accomplished by a simple replacement and exchange of the semi-auto original cover assembly for a surplus SMG, ratcheting type unit. This would be considered the most desirable method for this assembly, though modified semi-auto units are also common and perfectly acceptable, though less military looking.

The final aspect of the conversion is the installation, a drop in job now, of an original solid face, SMG style open bolt and its attendant recoil spring and buffer assembly. This bolt should already come equipped with a wide-lip SMG style extractor claw, but if not it should be exchanged for one.

With a complete exterior refinish, this is the ideal state of conversion in a complete conversion of the semi-auto carbine into as near as possible a clone of the factory produced, select fire, open bolt, SMG original, save for the mounting pin holes for the lower trigger housing and the semi-auto model A/B markings. These trigger housing pinholes and the receiver markings could have been altered if a registered receiver gun was remanufactured by a Class II manufacturer, but conversions using registered bolts cannot alter the receiver or its factory markings. As can be readily seen, since there exist such a wide range of possible conversions out there, respective values also vary widely. Most desirable would seem to be a fully converted registered receiver gun exhibiting all the alterations to render a near perfect copy of the factory SMG. These guns, circa early 1998 prices, are fairly priced in the mid to high $2000s for excellent condition guns with a known pedigree originally done by reputable sources, to the low $1200 range for a no-pedigree gun with mechanical or major aesthetic problems. Value increases with higher content of SMG style parts, or modifications to accept those standard parts. Registered bolts are fairly priced from $500-$1000 alone, depending on manufacturer and condition, and materials and methods used for manufacture. A complete bolt gun will depend upon the host semi-auto guns inherent value and whether any additional allowable alterations exist. These could command as a package anywhere from the low $1000s to the mid $2000s. As a general rule ANY bolt gun is worth less than a registered receiver conversion of comparable condition. Though, if you happen to run across one of the few very early conversions, those that fall under the heading of anomalies, such as those that contain a NFA registered selector lever, or are a registered receiver gun with a grandfathered un-registered slotted bolt, judgment will have to be used as to value based upon overall condition and the wear and tear on the registered part(s). Negotiations are in order, as there is simply no definitive value basis.

Hopefully now, with an understanding of the myriad definitions extant of the Conversion Uzi, a clear picture can be drawn of the complex nature of this particular class of civilian legal NFA firearm and its convoluted path to the marketplace and firing lines across the country. While there exists a large variance in this class of guns, it is also nice to know that they represent a solid value for the collectors money, while being easy to shoot and service, as spare parts and accessories are abundant and inexpensive.

After the overthrow of the Qing Dynasty, Chinese leader Sun Yat Sen confirmed the Republic of China on 10 October 1911 and China then embarked on 40-plus years of internal struggle and war. During the 1920s China was embroiled in a civil war between the Chinese Communist forces led by Mao Tse-tung and the Chinese Nationalist Party (Kuomintang) led by Chiang Kai-shek, who took control of the Kuomintang Party and the army during 1926. With China embroiled in a bitter civil war, Japan saw the opportunity to advance on Manchuria in northeast China during 1931. Manchuria was easily taken and occupied by the Japanese until the end of World War II. The Japanese attacked again on 7 July 1937, troops poured into China, attempting to occupy the five Western provinces. Chiang Kai Shek was caught between fighting the Communist Chinese and the Japanese; he focused on defeating his Chinese rivals.

During World War II, the United States became allied with the Chinese Nationalists and provided massive military aid through the United States’ Lend Lease Program to assist China in defeating the Japanese. The Chinese were supplied with large amounts of U.S. small arms. The wartime plan of the U.S. was to assist China in becoming a strong ally and a stabilizing force in Asia after the war. When World War II ended the Chinese civil war intensified, eventually resulting in a Communist victory in 1949. The Nationalist government left the mainland and settled on the island of Formosa (Taiwan) located off of the southeast coast of the mainland. Communist leader Mao Tse-tung renamed mainland China the Peoples Republic of China.

The Chinese Type 36 Submachine Gun

After the end of World War II and the U.S. Lend Lease Programs, the Chinese began to copy and manufacture weapons of both Soviet and U.S. designs. One of the U.S. weapons they copied was the U.S. M3A1 submachine gun, commonly known by its nickname “Grease Gun.” The M3 and the product-improved M3A1 were first designed and fielded by the United States during World War II. The first Chinese M3A1 clone produced on mainland China was adopted in 1947 and thus designated as the Type 36. The designation came from the Chinese Republic calendar year that started in 1911 when the Republic of China was established by Sun Yat Sen. The Chinese .45 caliber Type 36, manufactured at the Shenyang 90th Arsenal, near Mukden, China was a near exact copy of the U.S. made M3A1, except for the Chinese markings on the magazine housing. Reportedly fewer than 10,000 Type 36 submachine guns were produced before Communist forces overran the factory.

The Chinese Type 37 Submachine Gun

Like the Chinese Type 36, the Type 37 was a very close copy of the U.S. M3A1 submachine gun, except the Type 37 was chambered for the 9mm Parabellum cartridge. The Type 37 was manufactured at Mainland China’s 60th Jin Ling Arsenal located in the city of Nanking, China, then the capital city of the Nationalist Chinese. The Type 37 designation of the weapon indicates that it was adopted and manufactured during 1948.

The 9mm Type 37 submachine gun differed only slightly from the Type 36, and was basically a conversion of the .45 caliber Type 36 model. To facilitate the 9mm cartridge, the barrel was extended 8mm further out of the rear of the barrel nut than a standard .45 caliber barrel. This was necessary to reliably feed the shorter 9mm round into the barrel’s chamber. The rear of the 9mm barrel is slightly larger near the receiver end where it is pressed into the muzzle nut. The bolt is similar to the .45 model, except the bolt face was recessed 8mm further to compensate for the portion of the barrel protruding rearward. To feed the Type 37, a copy of the British Sten magazine was used. To permit the 9mm magazine to fit into the magazine well a three-sided magazine adapter was fabricated from a piece of .030 of an inch thick spring steel. The adapter was held in place by two metal tangs on each side. The standard M3A1 magazine release was used. To remove the 9mm magazine adapter the release button must be removed. The adapter is identical to that used in the World War II U.S. 9mm Grease Gun conversion kit, except there are no caliber or drawing numbers present.

The Type 37 was only manufactured for a brief period before the Communists overran the city of Nanking during April of 1949. Prior to the Communist takeover of the Arsenal, the Nationalist Chinese fled to Formosa taking most of the manufacturing equipment with them. Once settled on Formosa, production of the 9mm Type 37 resumed and redesignated as the Type 39. The submachine guns manufactured on Formosa are marked with the logo of the new ordnance department established there, the Combined Service Forces.

Brief History of the M3 and M3A1 Grease Gun

As early as 1939 the United States Ordnance Department had set a number of requirements for a new weapon to replace the expensive Thompson submachine gun.

U.S. Submachine Gun, Caliber 45, M2

There were extensive trials held at Aberdeen Proving Ground in Maryland to test and evaluate foreign and domestic submachine gun designs, which could meet or exceed the Ordnance Department’s requirements. One of the George Hyde designs was considered for adoption early in 1942 as a substitute standard to begin replacement of the Thompson submachine gun. The weapon was selected as a direct result of testing at Aberdeen and was one of several designs submitted by Mr. Hyde. Several prototypes were tested before a final model successfully passed the service test. In April of 1942 the United States adopted the weapon as the U.S. Submachine Gun, Caliber .45, M2. The Marlin Firearms Company was chosen to manufacture the M2.

There were many problems encountered with the production of the M2, and there were still some flaws in the basic design. Several of the M2’s internal parts were designed to be manufactured by powder metallurgy technology and a difficult time with the manufacturing process was encountered partially because of the aforementioned process. The technology was not advanced enough at the time to successfully utilize the method. The parts then had to be redesigned for machining from steel bar stock and this added substantial man-hours to the M2 production time.

While solving problems with the M2 submachine gun were being addressed, the prototype T-20 (M3) submachine gun was tested and evaluated; the weapon had all of the characteristics that the Ordnance Department was looking for. In an Ordnance Committee meeting held in November 1942 it was reported that, “The development of a caliber .45 submachine gun and a 9mm submachine gun: The requirements for these two weapons have been met by the development of a caliber .45 machine pistol which can be converted to 9mm operation by changing the barrel and bolt.”

The T-15 and T-20 Submachine Guns

The select-fire T15 was the prototype of what would become the M3 submachine gun. Like the M2 submachine gun it was designed by George Hyde. The T15 weapon used no critical metals and required a minimum of time-consuming machining. Except for the barrel and bolt assembly the entire weapon was constructed from simple sheet metal stampings. The bolt was designed to ride on two steel rods that were secured by two holes stamped into the rear of the receiver. The rod and bolt assembly was held in place by the barrel that simply was screwed into the front of the receiver. The bolt would slide on the two steel rods never contacting the inside of the receiver. This kept the moving parts impervious to dirt, making it an extremely reliable design. As the project progressed, there were a few changes. One was a lower cyclic rate, and a full automatic only operation. The new prototype weapon was designated the T-20.

The U.S. M3 Submachine Gun

U.S. Army Ordnance R&D officer Réne Studler recruited General Motors to assist with the T-20 development. Fredrick Sampson, chief engineer of GM’s Inland Division was assigned to the project. After a brief, but thorough evaluation of the T20 prototypes, the T20 was officially adopted as the U.S. Submachine Gun, Caliber .45, M3. The M3 – T20 prototype had an overall score of 95 out of a possible 100 in the Aberdeen test, higher than any previous weapon tested. The time period between the conception and production of the M3 submachine gun was an unprecedented seven months. The project was authorized in October 1942 with five working prototypes available for testing by November 1942, and the M3 was adopted by the United States Army on Christmas Eve 1942. The M2 submachine gun contract was canceled when the M3 submachine gun went into production. The initial cost of the M3 was $17.93 per unit, minus the bolt assembly. The contract for the M3 bolts was awarded to the Buffalo Arms Company at a cost of $2.58 per piece.

The U.S. M3A1 Submachine Gun

After the M3 was in service for a period of time the Ordnance Department felt that most of the problems with the weapon design had surfaced and they set requirements for improving the initial design. One of the biggest problem areas with the M3 was with the cocking handle and its related parts. A new bolt was designed that was cocked by the finger of the operator, eliminating the need for a cocking handle. An enlarged ejection port was also needed to incorporate the new style bolt. The new model was standardized as the M3A1 December 1944 and the M3 was then classified as substitute standard. Other improvements and changes incorporated in the M3A1 were: A larger oil container that was contained inside the pistol grip, a new stock design that served as a cleaning rod and a magazine loading tool. The stock could also be used as a wrench to remove a tight barrel, a new barrel nut that had “flats” machined on it so a wrench (or the stock) could be used to easily remove it. The rear guide rod retainer was redesigned so it would clear the ejector, allowing the bolt assembly to be removed from the receiver without removing the ejector housing. Guide Lamp production ceased in August 1945, after manufacturing 606,694 M3 and 82,281 M3A1 submachine guns. An additional 33,227 M3A1 models were manufactured by Ithaca in 1955-1956. The Ithaca M3A1 was nearly identical to the World War II M3A1 weapons manufactured by Guide Lamp. The M3A1 remained the standard U.S. submachine gun until 1957. In addition to China, the M3A1 design was copied and manufactured in Argentina as the P.A.M. 1.

(Special thanks to The United States Marine Corps National Museum, Triangle, Virginia, Mr. Al Houde, Arms Curator, United States Marine Corps National Museum, Quantico, VA, and Mr. Dolf Goldsmith, Texas. The Type 37 submachine gun photographed for this article courtesy of the United States Marine Corps National Museum, Triangle, VA.)

After World War II, the French Army wanted to adopt a new submachine gun to replace the various British, German and American guns that their troops were then equipped with. The request had a sense of emergency as a new war was brewing in Indochina. Both the state factories in Châtellerault, Saint-Etienne, Tulle and the private arms manufacturer of Hotchkiss began work on this project.

The Hotchkiss Company, established by Benjamin B. Hotchkiss in 1867, was initially devoted to the production of solid cased ammunition during the 1870-71 war. Later, he developed the Hotchkiss Revolving Cannon that was used by many countries at the end of 19th century. The most successful gun the company ever produced was the Hotchkiss machine gun developed by Laurence Benét and Henri Mercié at the turn of the 20th century and used to great effect during World War I.

During the 1920-30s, Hotchkiss developed light machine guns, infantry machine guns, aircraft machine guns, large-bore weapons and anti-tanks guns for armies throughout the world. After 1945, the Hotchkiss firm produced submachine guns for the French Army and others.

General Information on Hotchkiss Submachine Guns

The general appearance and operation of the Hotchkiss submachine guns is the same for all their models. They have a cylindrical frame with the cocking lever and ejection port both located on the right side. Depending on the model, they may have a fixed or folding stock made of wood or metal. Some models have a short telescoped barrel that can be pushed to the rear inside the frame, while others have a fixed barrel with a cylindrical cooling jacket. The magazine is derived from the MP 40 magazine and is located in a folding magazine holder. The guns works with a blowback bolt with a delayed firing pin. The guns are relatively complicated being made with many parts. Firing devices are complicated and are made of many parts with numerous parts being made of stamped sheet metal.

Model 011

The Model 011 has a rigid wooden stock, is very simple in its manufacture and is as crude as the Sten submachine gun. The triangular stock has a vertical bar on the left side for attaching a sling. The stock is assembled with an end cap that closes the frame at the rear. The sear mechanism is located in a triangular shaped box under the receiver frame. The magazine well is also a front grip that can be folded permitting the gun to be carried with a loaded magazine under the barrel. The ejection port has a cover that can lock the bolt in the opened or closed position and is used as a secondary safety. The barrel is located in a socket that can move to the rear for carrying thus reducing the length of the gun. The rear sight is located on top of the stock end cap and the front sight can be folded.

This model was developed in 1948 and was used by local units in Indochina, such as Phat-Diem Bishop Suppletive Guard.

Model 010 or “Type Universal”

The Model 010 is probably one of the most curious submachine guns ever made. Most of the components can be moved to reduce the volume of the gun for carrying:

• The metallic tubular stock can be folded under the frame,
• The pistol grip can be folded forward enclosing the trigger guard,
• The magazine housing can be folded forward under the barrel,
• The barrel can also be moved rearward.

The receiver frame is of a tubular shape with a flap to cover the ejection port that is located on the right side. The cocking handle is spherical and is also located on the right side. It holds a sheet strip to cover the grove upon which it moves. The bolt has a separate firing pin and the recoil spring is helicoidal. Ignition of the primer is delayed until just after the bolt is closed and is actuated by a lever. The trigger housing is a triangular box located under the receiver and contains a push-through button selector. The magazine is located in a forward folding housing. The stock is made of an assembly of tubes with a wooden shoulder rest. The pistol grip is equipped with brown plastic grips. The folding rear sight has two apertures and the front sight is protected by a hood.

Disassembly the Hotchkiss Model 010 is straight forward:

• Remove the magazine and clear the gun,
• fold the stock,
• remove the rear plug,
• extract the recoil spring and bolt.
• Reassemble in reverse order.

The Model 010 is a very complicated gun and is not easy to use; particularly during handling as it is easy for fingers to get caught and/or pinched in any one of the many folding parts.

The gun was manufactured between 1949 and 1952. It was tested by the French Army in Indochina by paratroops and the Foreign Legion. Some countries did buy a few of these guns such as Venezuela and Morroco. The last Hotchkiss Model 010 at war were found in Afghanistan in the 1980s.

Model 017

The Model 017 is designed like the Model 010 except it has a fixed wooden stock, a longer barrel, a perforated cooling jacket and the pistol grip cannot be folded. An additional safety device is installed near the trigger and when it is in place the use of the trigger is not possible. The Model 017 was designed for police use and was tested by the French police; but the MAT 49-54 was chosen instead. The Hotchkiss Model 017 was also tested by Morocco.

Model 304

The Model 304 is an evolution of the former models. It has a fixed wooden stock and several variations exist:

• tubular receiver frame, short barrel that can be retracted in the frame and a rectangular trigger box mechanism;
• tubular receiver frame, long barrel with a perforated cooling jacket, rectangular box trigger mechanism and a reversible spike bayonet like the MAS 36 rifle;
• sheet metal frame with dust cover on the ejection port, long barrel with a perforated cooling jacket, triangular trigger box mechanism and a reversible spike bayonet like the MAS 36 rifle.

Specifications

The 137th National Rifle Association Annual Meetings & Exhibits were held in Louisville, Kentucky on May 16-18, 2008. Louisville provided a wonderful venue for the largest convention ever hosted by the city. Firearm and accessory vendors assembled for the weekend exhibits at the Louisville Expo Center to display their wares in a setting similar to the S.H.O.T. Show. Since 1960, the NRA has provided space at the exhibits for collector displays, where affiliated clubs may apply to feature their firearms and related material for public viewing.

Members of The American Thompson Association (TATA) participated in the event, and assembled a historic display that will surely be remembered for many years to come. With the support of the Berrien County, Michigan Sheriff’s Department, TATA displayed the two notorious Colt Thompsons used in the St. Valentine’s Day Massacre on February 14, 1929.

The effort focused upon Dr. Calvin Goddard’s crime scene investigative techniques, and respectfully presented the two Thompsons. Dr. Goddard had previously worked on the Sacco & Vanzetti case of the late 1920s, where he established some of his forensic principles. Immediately following the St. Valentine’s Day Massacre, Dr. Goddard’s expertise was sought to assemble a crime lab at Northwestern University in Chicago to enable investigation of the case. It was the massacre of the century, purported to have been initiated by gangster heavyweight Al Capone, and law enforcement wanted to solve it quickly. As a result of the murders, and the subsequent investigation, Dr. Goddard pioneered many standard forensic methods used by law enforcement, including acid etching to reveal a ground off serial number on Thompson #7580, as well as rifling, cartridge case, and primer marking forensics.

Colt Thompsons serial number 2347 (Model of 1921A), and serial number 7580 (Model of 1921AC), which were recovered from a Berrien County hideout of “Killer” Fred Burke in December 1929 were featured on display. Also included on display were many artifacts, including one of three bullet proof vests recovered from Burke’s weapons cache, two bricks from the wall of the building where the murders occurred, an original full box of ammo from the same lot as used in the killings, various drums and magazines from the hideout, as well as several Goddard ballistic test artifacts.

The American Thompson Association was also fortunate to obtain the support of the Newark, Ohio Police Department, who lent their ballistic comparison microscope, which appeared on interactive display to the public. The microscope demonstrated some freshly spent cartridge casings from Colt Thompson #7580, and attendees could examine the markings left by the weapon on the casings as its own, distinctive fingerprint. The casings could also be compared to sample photos from the report produced by Goddard, showing the same markings.

The two Thompsons on display were undoubtedly the best documented firearms in the entire exhibit hall. Their provenance was apparent, as they could be spotted in several period photographs on display, and their descriptions and involvement in the murders were forensically proven in Goddard’s investigative report. It should also be noted that the deeds performed by gangsters with the two Thompsons drove much of the anti-machine gun sentiment of the time, and more than likely inspired passing of the National Firearms Act of 1934, therefore affecting many of our actions today. The Thompsons are truly historic artifacts for many reasons, and this was the first time they appeared to such a large audience, with over 71,000 attendees. Some fortunate audience members received unique souvenirs from the display; actual bullets and shell casings with documentation indicating they were fired through one of the SVDM Thompsons. These were highly sought mementos, and did not last long.

Goddard’s work was presented to a Coroner’s Jury to account for the seventy .45 ACP shell casings, and two “Climax” Brand 12-gauge shotgun shells found at the scene. All ammunition used was manufactured by the U.S. Cartridge Company. At the time he presented the evidence, the weapons had not been recovered. Goddard was able to determine the killings were performed by two different Thompson Model of 1921 submachine guns; one emptying an “L” drum of 50 rounds (later determined to be #2347), and one presumably emptying 20 rounds out of an “XX” magazine (later determined to be #7580). There were also two shotgun rounds fired from the same pump or automatic shotgun, probably as a “coup de grace” to Reinhardt Schwimmer, an optician by profession, and a gangster “groupie” who found himself in the wrong place at the wrong time on that fateful day.

It is important to note that no one was ever prosecuted for involvement in the St. Valentine’s Day Massacre. Captured in 1931, Fred Burke was jailed for life for the murder of police officer Charles Skelly of the St. Joseph, Michigan Police Department. Burke died in prison of a heart attack in 1940.

As a result of the amazing display, and the provenance of the Colt Thompsons, each Thompson was awarded a silver “Best Arms” medal by the NRA. To top it off, the overall effort won the 2008 “Best Display” award, which is a perpetual silver cup that is engraved with the winner each year. Very significantly, this was the first time that all 11 NRA judges unanimously chose one display to receive the top honor. Also awarded was a certificate of recognition for the accoutrements on display from Dr. Goddard, including pictures from his report, and boxes of labeled test bullets from his laboratory.

The display was produced through the efforts of several individuals. First of all, Lt. Mike Kline, who is the caretaker of the SVDM Thompsons in Berrien County, Michigan, and also Sheriff L. Paul Bailey supported the project. Tracie Hill, President of TATA, put together the incredible display, and coordinated the club’s involvement. Many tireless hours were spent by Tracie to make it possible, and his experience with previously designed firearms displays proved invaluable. Also critical was Chuck Schauer, whose display at the 2006 TATA Show & Shoot inspired this one. Mr. Schauer initiated the involvement of Berrien County, without whom the SVDM Thompsons would never have been possible to display. Also, Bill Helmer, author of the 1969 classic Thompson narrative, The Gun That Made The Twenties Roar, contributed artifacts and much of the historical account that was featured in the program handout that accompanied the display. Many other TATA members helped with construction, and staffed the display while providing historical tutelage to those who viewed it on Friday, Saturday, and Sunday.

Much fun was had by all who participated from the club, and countless people were amazed and grateful for the opportunity to view such historic firearms presented in an interactive manner. The NRA provides an unbeatable collector display forum, and attending their annual events held in cities around the country is highly recommended. Nowhere else can one see so many firearm displays, vendor exhibits, along with Ted Nugent’s enthusiastic support of the second amendment, followed by his amazing guitar rendition of the “Star Spangled Banner,” all in the same day. The next NRA Annual Meetings & Exhibits will be held in Phoenix, AZ, May 15-19, 2009.

In 1933, F.N. Herstal manufactured under license the Heinneman submachine gun, which was presented to several countries in Europe. The weapon had a complex mechanism with a lateral toggle-joint system of locking; working like the Luger pistol. Belgium was not interested in it and it adopted a local copy of the Schmeisser MP 28/II submachine gun, under the name of Machine Gun Model 1934, and was manufactured under license by Pieper.

After WWII, Belgian troops were primarily equipped with English material and particularly with Sten submachine guns and to a lesser extent with the American Thompson.

With the beginning of the 1950s, Belgium, which had just adopted the semiautomatic SAFN 49 rifle, also wished to bring into service a national designed submachine gun. Several models were put to test:

• Many prototypes from F.N.,
• Submachine gun RAN, designed by Vitold Porebski in 1954 and manufactured by Repousmetal in Brussels,
• Submachine gun Racour, a copy of the Sten Mk II, realized in 1952,
• Submachine gun M.I. 53, an improved variation of the Sten Mk II manufactured by Imperia in Nessonvaux, close to Liege,
• Submachine gun Vigneron.

After several trials, the Belgian Army chose the Vigneron. It was designed by retired Belgium Army Colonel Georges Vigneron. The invention is covered by the Belgian patent No. 502.942 and 156.000 and the gun was manufactured by Précision Liegeoise S.A. in Herstal.

The initial version adopted in 1952 was designated as the M1. The weapon has a Z shaped metal wire stock, a peep rear sight, no protection for the front sight, and no selector. It was replaced two years later by an improved version designated Mitraillette Vigneron M2. All the Vignerons whose serial number is higher than 21,300 are of the M2 type and the earlier M1 models were modified and a 2 was struck overprinting the 1, which appeared in the marking designation.

Description

The receiver is made of a 34 mm steel tube, threaded at both ends. At the front is a screwed ring that retains the barrel. The barrel is tapered with cooling ribs to the back part and a compensator at the muzzle. The front sight is hooded for protection. The barrel is 9mm and has six right-hand grooves. The rear of the receiver is sealed by a screwed plug.

A sleeve consisting of the magazine housing is welded over the receiver. It contains the ejection port which has a folding cover that can be automatically opened when the bolt moves either in the closing or opening position.

A lion, the symbol of the Belgian Army, is located on the right side of the magazine housing. Markings on the left side of the magazine housing are:

• ABL (for Armée Belge or Belgian Legeer) 52 (or year of manufacture)
• VIG M2
• Serial number

The magazine was derived from that of the MP 40. As there was an abundance of MP 40 magazines left over from the war, they could be used as well. The magazine is retained by a transverse push rod.

The cocking handle is located on the left side of the gun. The pistol grip contains the trigger mechanism and has two synthetic material grips. The side faces of the grips are checkered and marked with CMH. Just above the trigger one can read on the left face of the trigger pack Systeme Vigneron. The trigger pack contains a grip safety, connected to a bolt stop by a rod, the trigger, a connection lever, sear, and a rotary selector switch on the left side with R for single shot, A for automatic and S for safety.

On each side of the trigger pack just below where it meets the receiver tube are two tubes with a transverse push rod to receive the two branches of the stock. The stock is of the trombone type, with two stems and can be adjusted to four positions. The right stem is longer than the left and is flattened at its end to be used as a cleaning-rod.

The bolt is cylindrical with integrated firing pin. The recoil spring is comprised of 16 whorls and the diameter of the first third of the spring is smaller than the remainder.

The front post sight is protected by a hood and the rear aperture sight is set for shooting at 50 meters.

The weapon is parkerized and painted black. Accessories include a sling in khaki fabric, loading tool, blank firing barrel, and a sleeve for the launching the Energa grenades.

Disassembly

Remove the magazine and clear the gun. Take off the stock. Unscrew the barrel ring to separate this element from the receiver. Unscrew the rear plug and remove the recoil spring. Extract the bolt from the receiver tube. Remove the grip. Reassembly is carried out in the reverse order.

Distribution

The Vigneron submachine gun was used by the Belgian Army, up to the 1980s. It was also used in the former Belgian colony of Congo by the police force (named Force Publique), then by the various factions which clashed in ex-Belgian Congo, Katanga and Zaire.

Further Experimental Prototypes

Colonel Vigneron continued his research and developed improved versions of the M2 submachine gun (correspondence with the author in the 1970s):

• Submachine gun “X”. This modification was covered by Belgian patent No. 675.720 and is a simplified version of the M2 model and is characterized by a reduced number of parts (18 instead of 40). Additionally, the safety lever is placed on the left in front of the trigger, the selector is on the right and the sights are mounted on the receiver.
• Recoilless submachine gun, invention covered by Belgian patent No. 738.604. This unique gun was provided with a gas exhaust system to reduce the recoil.

None of these weapons were produced in series.

Vigneron M2

Ammunition: 9mm Luger
Overall length: 0.887 m (34.92 inches)
Length with stock folded: 0.612 m (24.1 inches)
Barrel length: 0.305 m (12 inches)
Weight without magazine: 3 kg (6.61 pounds)
Magazine capacity: 32-rounds
Cyclic rate: 500 rpm

By the end of World War I it became apparent that automatic firepower was needed for mobile warfare to improve combat efficiency. The solution was a new type of military weapon firing a pistol cartridge; a weapon between a pistol and a rifle that could be fired from the hip or shoulder. The result was the submachine gun, a hand-held, light automatic, magazine-fed weapon for short range combat.

In south-eastern Europe on the Black Sea, Romania was well aware at the beginning of World War II of the importance of developing their armament industry. The main Romanian manufacturer of infantry weapons and small arms ammunition was the Cugir factory that had emerged as a metallurgic center in 1799. During World War II, the Cugir factory from Transylvania was part of the military-industrial complex C.M.C. (Copsa-Mica Cugir). Due to a high technical potential, in early the 1940s, the Cugir factory made the first submachine gun of Romanian conception: the Orita model. Romanian Captain Marin Orita was responsible for a few military designs, but his crowning achievement is the 9mm Orita M1941 submachine gun that bears his name. In 1949, at the age of 52, Marin Orita ended his 25 years of military service.

The 9mm Orita M1941 submachine gun was first issued in 1943 to Romanian troops fighting on the Eastern Front, at a time when the foot soldier’s weapon was the Czech made 7.92mm Model 24 (vz.24) rifle called by the Romanians Pusca ZB. This new automatic weapon greatly improved the firepower of Romanian troops who had been at a disadvantage facing the fast-firing Russian submachine guns. During the campaign of 1944-45 when the Romanian troops were fighting the Wehrmacht liberating Hungary and Czechoslovakia, the 9mm Orita M1941 submachine gun was issued on a larger scale proving its worth.

Chambered for the 9x19mm Parabellum pistol cartridge, the Orita M1941 submachine gun is blowback operated and fires from an open bolt. There is no mechanical locking of the bolt. The weapon will fire if the bolt moves forward with a loaded box magazine in place. The massive bolt used by the Orita M1941 has an incorporated firing pin and inside hammer. Since the firing pin does not stay permanently to the front of the bolt, there is no risk of detonation before the bolt is completely closed. As the bolt closes, the hammer hits against an outside projection in the bolt-way and a pivoting movement starts. The hammer rotates in the bolt and the other end of it strikes the firing pin that moves forward to hit the cartridge primer. This unusual system as used by the Orita M1941 is very safe since the hammer cannot hit the firing pin before the action is closed. There is a good balance between the bolt and the recoil spring. A heavier stiff recoil spring brings up the cyclic rate of fire but a heavier bolt will decrease it.

The Orita M1941 submachine gun has a vertical fire selector switch located on the right side of the receiver about 3 inches (77mm) behind the rear sight. There are two marked positions: “A” for full automatic with the selector pushed down and “1” for semiautomatic with the selector pushed up.

A horizontal button safety in front of the trigger guard could be moved from side to side. To fire the weapon, the safety had to be pushed from right to left. The left end of the safety button had an L-shaped device that blocked the firing mechanism when the safety was pushed from left to right and the weapon could not fire. This safety button proved to be unreliable and was later removed. An empty hole is visible in front of the trigger guard if the spot was not filled and repaired. A new vertical switch safety was installed parallel to the rear sight on the right side of the receiver. This manual safety is pushed up for FIRE, down for SAFE.

The foresight is a sturdy blade with perforated guard wings on either side and is located at the very end of the barrel. The foresight blade is adjustable for windage. The weapon has a well protected open V rear sight calibrated up to 500 meters (548 yards), which is adjustable only for elevation. This maximum range seems to be overly optimistic, but it was in keeping with some other 9mm submachine guns of the time that had rear sights graduated up to 500 meters or more; such as the German MP28, Finnish M31 Suomi, Italian Beretta M1938A, British Lanchester Mark I and Czech ZK383.

The 9mm Orita M1941 submachine gun is fed by a dependable 32-round detachable box magazine inserted vertically from below the receiver. The weapon has an excellent magazine housing which is well projected from the receiver wall and serves as a forward grip for the shooter’s hand. A box magazine must be inserted 2.5 inches (65mm) into the magazine housing to be locked right. A serrated magazine catch-release is safely located on the rear of the magazine housing, making an accidental manipulation less possible. The Orita magazine holds cartridges staggered in two columns, with single-position feed. It has no indicator holes for the loaded ammunition and it can be identified very easy because of the two long deep ribs indented into each side of the magazine body from top to the very bottom. These four ribs give more strength to the magazine body and at the same time reduce the internal friction. Having an unusual shape, the magazine follower is machined from solid steel, which is highly polished. The 32-round Orita box magazine uses a 24 by 25 turns conventional compression spring in elliptical shape. A depression is stamped into the back edge of the removable floorplate to help it to lock into the right position. Some 25-round Orita box magazines were manufactured too.

In 1943, Captain Orita patented a magazine loading tool that has a length of 9.1 inches (232mm) and weighs unloaded 13.7 ounces (0.388 kg). This unusual device has four interior prongs and at the top there is a vertical steel cartridge guide that can be loaded with a maximum of 15 cartridges. It locks into the Orita box magazine and, rotating the handle clockwise, the cartridges are loaded rapidly by a tangential motion.

The 9mm Orita M1941 has a fixed semi-pistol grip style wooden stock with a metal buttplate. The forearm extends up to the magazine housing. The steep angle cut into the stock provides a diagonal angle for the trigger hand. The shape of the one piece long wooden stock differs slightly depending on the Orita submachine gun variant. There are sling swivels mounted by the front end of the receiver and on the right side of the wooden stock. The cocking handle is located on the left side of the receiver. This arrangement helps the shooter to change the box magazine and to retract the cocking handle using the left hand while the right hand is kept near the trigger. The cocking lever folds down.

The disassembly procedure for routine cleaning and maintenance is simple. After removing the box magazine and making sure the weapon is clear, the serrated cap from the end of the receiver is unscrewed to release the return spring which is compressed. The circular receiver cap differs slightly in length depending on the Orita variant and it is secured in place by a simple device. The bolt is taken out and the Orita submachine gun is field stripped.

Very well constructed, the Romanian 9mm Orita M1941 submachine gun is made from 78 different parts and is polished blue finished. The trigger group components and the sear are made of heat-treated steel. The receiver is machined from a high-quality steel forging and very few stamped sheet metal parts were used. The manufacturing process was expensive and time consuming: but such is the case for quality.

Although the Orita M1941 was highly regarded and performed well in combat, actual service revealed two shortcomings: the pistol grip was prone to breakage and the weapon could accidentally discharge if dropped or mishandled while it was cocked. A fault very common to all open bolt submachine gun designs.

Shortly after 1945, the surviving wartime Orita M1941s were modified at the Cugir factory. It was a large operation directly conducted by Marin Orita. The result was a simplified model known as 9mm Orita M1941/48 or Model 48. Today, the original unmodified 9mm Orita M1941 submachine gun is an ultra rare weapon that would be prized in any collection.

The Orita M1941/48 has no fire selector: it fires only full automatic. The initial fire selector switch from the right side of the receiver was removed. The previous vertical safety switch located parallel to the rear sight on the right side of the receiver was removed as well. The modified weapon was fit with a grip safety at the rear of the trigger guard. This new safety may sometimes be found in various shapes. The unrealistic rear sight calibrated up to 500 meters was replaced with dual flip-up apertures set for 100 and 200 meters. Damaged pistol grips were repaired and reinforced with metal or steel pins and some M1941/48s were fit with new wooden stocks. The position of the swivel fixed on the wooden stock was moved on the left side. Many old trigger guards with the hole at the front from the horizontal button safety were replaced. Some modified Orita M1941/48s use the same old receivers and some rebuilt weapons have new made receivers. An older receiver used by the M1941 can be recognized by the markings stamped on top of it and by the repaired spot where the vertical safety switch was located parallel to the rear sight on the right.

A scarce variant of the Orita submachine gun having a folding metal stock was manufactured at the Cugir factory after 1945. The new sturdy weapon has a large grip safety to prevent accidental discharge. A horizontally grooved wooden side plate is fixed on each side of the weapon. The cocking lever is knurled and it is directed upward at a 45 degree angle. A rear swivel is located near the mechanism that folds the steel stock. This was the first automatic weapon with a folding stock ever manufactured in Romania.

The top of the receiver used by the 9mm Orita M1941 submachine guns is marked: “UZINELE CMC CUGIR” over “P.U.A. ‘ORITA’ Md.1941 Cal 9mm” followed by a six digit serial number. The new receiver used by some M1941/48s is marked on top: “AUTOMATUL UMC 49” also followed by a six digit serial number. The total number of both models of the Orita M1941 and M1941/48 submachine guns made and modified at Cugir factory remains unknown today but the serial numbers may give us a clue. Some modified Orita M1941/48 submachine guns have old receivers stamped “Modificat 48” or “Model 48”. A triangle stamp with the letters “AA” inside means “Arsenalul Armatei” (Army Arsenal). Small quality control markings can be stamped as well.

The 9mm Orita M1941/48 submachine gun remained in Romanian army service up until the late 1950s. In the mid-1970s the weapon was still used for training by the so called Garzile Patriotice (Patriotic Guards), a kind of civilian national guard and territorial defense that had been created in Romania during the autumn of 1968 as a direct response to the soviet military invasion of Czechoslovakia in August the same year. By 1980, the remaining Orita M1941/48 submachine guns used by Garzile Patriotice were replaced with Romanian made 7.62mm Kalashnikovs.

While in Romania, the author had the rare opportunity to shoot the 9mm Orita M1941/48 submachine gun. It is well designed, easy to handle and accurate weapon. The box magazine is easy to insert and remove. Short two and three shot bursts can be fired through trigger manipulation. A large ejection port is located above the magazine housing on the right side of the receiver. The empty cases fly with good forceful ejection, landing about five feet away to the right. When fired from the shoulder the weapon has the tendency to climb fast if bursts are not controlled. This reliable Romanian burp gun is very comfortable fired from the hip with the magazine housing firmly gripped and the muzzle blast is moderate and not disturbing to the shooter.