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

Regular readers of SAR will no doubt recognize the name Michael Heidler, as he has contributed numerous articles over the years. He has also authored several books on military topics in his native German language. His latest book, The Complete History of America’s Famed “Grease Gun” (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 lion’s 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 such as the Thompson.

As noted in chapter one, 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 two 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 three 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 wooden “dust test” 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 WWII era B&W photos, patent drawings, US 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, magazine loader, magazine 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 USA and China, it was logical that the USA 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 shown.

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.

Specs

• Title: 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
• Dimensions: 8.5x11in
• Pages: 224 pages
• Photos: 551 B&W and color photos and illustrations
• Publisher: Schiffer Publishing Ltd.
• Website: schifferbooks.com
• MSRP: $45

For many years blank cartridges have been used by military organizations around the world to add a touch of realism to military training exercises. A blank cartridge is designed to simulate the report of a firearm, but usually does not expel a projectile. When firing blanks in a semiautomatic or automatic firearm, a device is needed to delay the propellant gas from escaping from the barrel long enough to cycle the action. Such devices are commonly known as blank firing adapters or simply a BFA. Blank adapters are attached to the muzzle of a firearm. Most U.S. military blank adapters are bright orange or red in color as a reminder that the device is on the weapon. Blank adapters used in the movie industry are designed to be less conspicuous to the viewer.

Outside of the military, the movie and TV industry are probably the largest consumers of blank cartridges. Prior to the availability of blanks, live rounds were often used in film making, creating a dangerous situation for both cast and crew. In the 1930s, actors James Cagney and Edward G. Robinson were nearly shot several times while portraying gangsters during filming. After a having few close calls both men refused to allow themselves to be fired at with live ammunition. Today, the use of live ammunition in films is unimaginable. However, despite enhanced safety measures and exclusive use of blanks, several actors have been killed with them. An incident occurred in 1984 when TV actor Jon-Erik Hexum, who was relaxing between takes, as a joke placed a .44 Magnum revolver loaded with blanks to his head and pulled the trigger. At point blank range, the paper wadding in the blank cartridge had enough energy to inflict a fatal injury. Another Hollywood actor, Brandon Lee, son of the legendary martial artist Bruce Lee, was accidently killed in March, 1993 during filming. In both cases it was a lack of awareness of the inherent danger and improper handling of firearms. Firing blanks can be dangerous! One caution that should be observed is that blank cartridges should never be fired at any persons or animals. Serious injury and even death can occur. A weapon firing blanks is not a toy: thus it is imperative that one be responsible.

Types of Blank Cartridges

Blank cartridges use a small charge of gun powder as a propellant with a primer to ignite the powder. To contain the propellant, the opening where a bullet would normally be located is crimped shut or sealed with some material that disperses rapidly upon leaving the barrel. This sealing material and hot gas can cause serious injuries at close range.

Some foreign made blank cartridges have a bullet made of wood or plastic in place of a crimp or sealing material. This type of blank uses a muzzle device that is designed to shred the “bullet” as it is expelled from the muzzle. This type of blank cartridge is very dangerous at close range. Most modern blanks usually do not fire any type of projectile.

Firing blanks with a blank adapter restricting the gas flow from the barrel is similar to using a sound suppressor: the firearm is going to get hot fast and dirtier than it normally would.

Grenade Launching Cartridges

Grenade launching cartridges are used to launch specially designed grenades from the barrel of a rifle. Although they may look like blank cartridges, they are loaded with approximately the same powder charge as live ammunition. Therefore, grenade launching cartridges would be VERY dangerous if fired from a weapon fitted with a blank firing device. When in doubt, never fire any unidentified “blanks” with a blank adapter attached. Listed below are typical loads used in blank and grenade launching cartridges to exemplify the significant differences.

* U.S. Cartridge, Blank, M1909 is loaded with 12 grains of SR4990 powder.
* U.S. Cartridge, Grenade, M3 is loaded with 45 grains of IMR4895 powder.

Flash and Bang

There are probably a large number of machine guns chambered for the 7.62mm NATO cartridge, (.308 caliber Winchester) sitting idle because of the current price of ammunition required to feed them. The number of Miniguns, M14s, FN FALs and the 1919A4 Brownings chambered in 7.62, normally present at machine gun shoots, have been conspicuously less in recent times.

A few years ago surplus 7.62mm NATO ammunition from South Africa, Australia and Great Britain was available in seemingly inexhaustible quantities; at Knob Creek nearly every vendor was selling crates of the ammo for 12 to 13 cents per round. Suddenly, it jumped to over 40 cents a round almost overnight. Oddly, many of those who wisely stockpiled the ammo when it was cheap are reluctant to shoot it despite having many thousands of rounds. This phenomenon of human nature has occurred before. In 1994, when steel-core 7.62×39 was banned and the ammo became scarce; those who had acquired huge lots of it at bargain prices, wouldn’t shoot it because it had become “too valuable.” The price of 7.62x51mm cartridges has continued to increase and for a time was impossible to find in any appreciable quantity. Likewise, reloading components, bullets, powder and primers for hand loading the rounds have become high-demand items, just recently becoming available.

Now there is a solution to the ammo shortage; 7.62mm NATO cartridges that can now be purchased for pennies a round, well sort of. The cartridges are blanks. The blank cartridges have been imported from Germany in fairly large numbers. They are non-corrosive, quite loud and can usually be made to function in virtually any firearm chambered for the 7.62 NATO round with the appropriate blank adapter. The blanks are made of OD colored plastic except for the rims and primers, which are made of cadmium plated steel, and can be policed up with a magnet after being fired.

Outside of Miniguns, one of the main consumers of 7.62x51mm ammunition have been the Browning 1919A4 machine guns, using the Israeli 7.62 NATO caliber conversion. The Brownings will run on the plastic blanks with a few minor alterations. One of the primary items needed of course is a blank adapter.

The 1919A4 Blank Adapter

Blank adapters are now being manufactured for the 1919A4 Browning machine gun, or semiautomatic clones, that will screw directly onto the (early style) two-piece bearing/booster of the 1919. The early booster is the one with the removable end cap. The blank adapter addressed here, looks exactly like an original cap except it has a very small hole in the end and is marked “BLANKS ONLY.”

The standard adapter comes with a .170-inch diameter orifice, which is normally sufficient to run most Brownings on the German blanks. However, the test gun used to evaluate the adapter for this article would not run without an unacceptable amount of stoppages. The solution was quite simple, the original hole was welded up, from the inside surface and drilled to a smaller diameter of .125 inches, this did the trick giving the old Browning enough backpressure to function reliably with the blanks.

In addition to the fixed-orifice blank adapter, the manufacturer offers a similar product that allows the size of the orifice to be manually adjusted. The adapter uses the same Browning two-piece booster cap, but in place of a fixed orifice, has a threaded hole and uses a set screw that is held in place by a jam nut. The replaceable set screw is available drilled in several sizes. This allows the shooter the option of adjusting the size of the orifice to a size that permits function in their particular gun without going through the welding and drilling process.

While the Parkerized blank adapter is aesthetically pleasing, mistakenly leaving in place while attempting to fire live ammunition will have catastrophic results. For this reason, SAR highly recommends painting the adapter red or orange so that is can be readily identified. High temperature paint will be needed as the adapter will get quite hot during firing.

The Front Cartridge Guide

Since the blanks are slightly shorter than live 7.62 NATO rounds, the Israeli front cartridge guide may need to be shimmed up a few thousands. This can be easily done by fabricating a shim from a small strip of steel and attaching it the front 7.62 guide with epoxy. Reportedly, some Brownings will run as is without the shim, but even so the use of the shim will decrease any chance of a failure to feed condition. For use in the Browning, the plastic blanks can be easily loaded in fabric belts or the Israeli steel links using the appropriate loading device.

The thrill of firing blanks in a machine gun is similar to firing live ammunition, and is useful for familiarizing new shooters to machine guns, or for having fun in an area where it may be unsafe to fire live rounds. Blanks can also useful for celebrating events like the 4th of July. However, be forewarned that most areas of the country have published ordinances that prohibit the discharging of a firearm, for example within city limits, or within a certain distance from occupied buildings. The authorities will sometimes regard firing blanks the same as discharging live ammunition. The key phrase that may be applied from the local ordinances is “discharging a firearm.”

Blank adapters for the 1919A4 Browning
Contact Jon at
Mr.Gadget Gunworks
MrGadget@earthlink.net

7.62x51mm Blank cartridges
Long Mountain Outfitters
(702) 564-0948
http://longmountain.com/store/

Veronesi Gunsmithing
(814) 275-4382

Two-piece 1919A4 Boosters
Ohio Ordnance Works Inc.
(440) 285-3481
www.ohioordnanceworks.com

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.)

During the Second World War, Germany fielded a number of new weapons produced from simple sheet metal stampings. The German 9mm MP40 machine pistol was the first successful sheet metal weapon to be made in large numbers followed by the German MG42 machine gun, and the Sturmgewehr. The MP40 weapon started a world revolution in small arms design. The methods and materials used allowed weapons to be manufactured cheaply and very quickly in large numbers – very advantageous during a large scale war. Weapons manufactured by these methods proved as durable as their labor-intensive counterparts made primarily of milled steel. One of the first designs fielded by the Allies was the 9mm British Sten Mark I in 1941. This was soon followed by the even more utilitarian Mark II and III Sten models.

Seeing the benefits of such a design, the United States Ordnance Department began to develop a similar submachine gun that was to be fabricated from mild steel sheet metal. After an in-depth study of the German MP40 and the British Sten by the Ordnance Department engineers, the requirements for a similar U.S. weapon were established on 6 February 1941. Development began by the Small Arms Development Branch of the Ordnance Department with assistance from the Inland Division of the General Motors Corporation. One of the first new submachine gun models to be designed was the T15 submachine gun. The T15 was a .45 caliber weapon that featured a straight open-bolt blow back operation commonly used in most submachine gun designs. The T15 quickly evolved into the simplified T20 model after several requirements were revised. One of the design changes was the elimination of semiautomatic function, and a requirement for the weapon to be easily converted to fire 9mm Parabellum ammunition. Because of the slow cyclic rate of the weapon it was decided that there was no need for a semiautomatic feature thus allowing the design to be further simplified.

The T20 had one very unique design feature that separated it from all other submachine guns of the day. On virtually all previous submachine gun designs, the bearing surfaces of the bolt would move forward and rearward supported by the inside surfaces of the receiver. On the T20 weapon, the bolt was designed with two horizontal holes that ran through the entire length of the bolt. The bolt then rode on two steel rods that were inserted into the holes, and were held in place by a steel plate oriented by two holes located in the rear of the receiver. Each guide rod had its own separate recoil spring. The steel guide rods were supported at the front by a steel guide plate that was indexed in the receiver by two integral tabs on the plate. A spring steel circular clip kept the bolt, guide rods and recoil spring assembly together until the barrel could be screwed onto the receiver. The front guide plate was secured to the receiver by the tightening of the barrel nut assembly. The primary advantage to the design was that the bolt never contacted the inside surfaces of the receiver. The unique arrangement made the T20 submachine gun nearly impervious to stoppages from dust, mud water or even sand. The T20 was one of the few weapons that was able to successfully pass the Ordnance Department’s rigorous mud and dust tests.

The receiver design of the U.S. T20 prototypes also differed radically from other submachine guns that used a simple circular tube for the basic receiver. When a tube receiver was used, a separate housing for containing the trigger and sear assembly needed to be designed and attached to the main tube. This would complicate manufacture somewhat as the two pieces would need to be accurately oriented to each other. In the design of the T20, the receiver was constructed by joining two separate stamped sheet metal pieces by welding. The receiver, the housing for the trigger and sear assembly, and pistol grip were all an integral part of the single assembly. The only other separate parts required were a dust cover/ejector housing for the trigger mechanism and a simple spring steel trigger guard that also held the cover in place. Other parts like the barrel bushing, sights and ejection port cover were attached to the receiver assembly by rivets or welding, no threaded fasteners were used.

The method of manufacturing barrels was borrowed from the British, who produced their Sten machine carbine barrels by the cold swaging method. The M3 barrel was also manufactured by cold swaging, a process that saved a significant amount of production hours. The steel tubing for the barrel would first be reamed to the correct inside diameter. The rifling would then be pressed into the barrel by inserting a mandrel and compressing the tube as it was forced through the die. The 40-inch piece of tubing would then be cut in sections to produce five M3 barrels. This barrel making process was much faster and less expensive than broaching or other methods. Accuracy of fire remained well within the requirements established by the U.S. Ordnance Department for submachine guns.

The T20 was recommended for adoption as the Caliber .45 Submachine Gun, M3 on December 24, 1942. The contract for manufacture of the M3 was awarded to the Guide Lamp Division of General Motors who were experts in sheet steel fabrication for the automobile industry. However, there were several problems encountered during initial manufacture of the M3. One of the problems was being able to accurately join the two receiver halves together by welding. A second problem was the thin sheet metal receiver halves were warping from the heat generated by the welding process. While Company and Ordnance engineers were engaged in resolving these problems, the Ordnance Department ordered the resumption of M1A1 Thompson Submachine Gun production.

The original M3 submachine gun production schedule had planned for 20,000 units to be produced by July 1943, but only 900 acceptable units had been completed. Before long the welding problems of the receiver were solved and the M3 was in full production. At the height of production in 1944 one-thousand M3 submachine guns were being produced every twenty-four hours.

The Guide Lamp initial contract price for the manufacture of the U.S. M3 was $18.36 per unit after being adjusted to cover the cost of minor production changes, and the packing of the completed units. There were a large number of subcontractors involved that supplied various small parts to Guide Lamp. The only major part that was subcontracted out was the bolt assembly, which was manufactured by the Buffalo Arms Company of New York. The manufacture of the M3 submachine gun was further simplified with the introduction of the M3A1 model in 1945.

While the unique design of the M3-M3A1 receiver made the weapons extraordinarily reliable, the design of the magazine proved problematic. It remains a mystery as to why the U.S. M3-M3A1 submachine gun was not configured to use the existing and excellent double stack-double feed magazine from the Thompson. The Thompson magazine was a proven design and already in production. Instead, the 30-cartridge M3-M3A1 magazine was a double stack, single feed design that contributed to stoppages when exposed to dust and mud. The single feed configuration had previously proved troublesome when used in both the British Sten and the German MP40 weapons. While the M3 was undergoing Ordnance testing, virtually all jams and stoppages were attributed to the weapon’s magazine. During testing of the M3 by the Infantry Board, they had suggested a few ways to improve the magazine’s reliability, but the problems were never addressed. The only fix was a rubber and eventually a plastic cap to keep dirt and debris out of the magazine. The cap was to be kept on the magazine until it was ready to be placed into the weapon.

Although many martial arms collectors of today are put off by the U.S. M3 and M3A1 submachine gun’s appearance and slow cyclic rate, the weapons were very cleverly designed. The M3-M3A1 has often unjustly received criticism based solely on its utilitarian toy-like appearance. The M3 and M3A1 submachine gun remained in U.S. service many years after most foreign and domestic World War II era weapons were declared obsolete.

Just a short while later the Germans simplified their original design of the MP38, by utilizing sheet-metal stampings, welded and pressed together. The result was a weapon that could be produced very inexpensively, but more importantly during a major war, manufactured in a short period of time. The new sheet-metal machinegun was called the MP40 maschinenpistole. Despite the fact that the weapon was made of inexpensive materials and methods it was just as reliable as the weapons that were produced from more traditional techniques. While fighting the Germans in North Africa in 1942, the American Army captured a number of MP40 weapons. These were promptly shipped to the Aberdeen Proving Ground in Maryland for evaluation and testing. The Ordnance personnel at Aberdeen were quite impressed with the methods and materials used to make the rugged German submachine gun.

The standard United States submachine gun issued during most of World War Two was the Thompson. The first model of the famous “Tommy Gun” that was procured by the U.S. Army was the 1928 model. The 1928 Thompson was of a design conceived over twenty years earlier. Although extremely reliable and rugged, the Thompson was very labor intensive to produce, heavy and expensive. The M1 and M1A1 Thompson was introduced in 1942, although simplified for ease of manufacture, they were still far too time consuming to produce in the numbers needed to supply the United States and her allies. The U.S. Marines were forced to adopt and procure 80,000 .45 caliber Reising submachine guns in 1942, due to the shortage of Thompsons.

The U.S. Ordnance department had started to test both domestic and foreign submachine guns as early as 1939, even as their first orders for the Thompson were being placed. The testing failed to find a suitable replacement for the Thompson. The Ordnance Department decided to develop their own weapon, the T-20.

The United States Army Ordnance Department recruited the General Motors Corporation to assist with the design and development of the T-20. The GM Inland Division’s Chief engineer Fredrick Sampson was assigned to head up the project. After the successful and thorough testing 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 standard Aberdeen small arms test, higher than any previous weapon tested.

On 29 January 1943 the Guide Lamp Division of the General Motors Corporation, and the U.S. Ordnance Department completed negotiations of a contract to manufacture the M3 submachine guns. The initial cost was $17.93 per unit, minus the bolt assembly. This cost would be amended several times during the life of the GM Guide Lamp contract. The contract to manufacture the bolts for the M3 was awarded to the Buffalo Arms Company of New York at a cost of $2.58 per piece. Ordnance contracts W-294-ORD-2107 and W-33-ORD-825 for the initial 300,000 units were awarded to Guide from the Cincinnati Ordnance District. The Guide Lamp factory was located in Anderson, Indiana. Guide Lamp was also manufacturing the .45 caliber sheet metal Liberator pistols, and Browning machine gun barrels. At the peak of production Guide was turning out a new M3 submachine gun every 2.4 minutes. A total of 605,694 M3 models would be accepted by the Ordnance Department from 1943 until early in 1944. The simplified M3A1 model was only produced in 1945, 82,281 were built before production ceased at the end of July.

The US .45 caliber M3 submachine gun, was an air-cooled, automatic only, weapon that fired from an open bolt. The weapon’s rate of fire was a somewhat slow 350- 400 rounds per minute. Semi automatic fire could be quite easily achieved by careful manipulation of the trigger. The U.S. troops that were issued the M3 were not immediately impressed by the new weapon, mostly because of its slow cyclic rate. They perceived that the effectiveness of any given weapon was directly related to the amount of rounds it could expend in a short period of time.

Although the cyclic rate was slow and the appearance unorthodox, the M3 was quite a reliable and effective weapon within its design limits. Its toy-like appearance generated several nicknames for the weapon, some not very flattering. The one that stuck was the grease gun, for its similarity in appearance to an auto mechanics tool. The M3 was easily manufactured from two die-stamped halves of sheet metal that were welded together. At first problems were encountered from the heat of the welding process warping the sheet metal receiver, but the problem was soon solved. The barrels were rifled by using the time saving cold swaging method. The bolt assembly was basically the only part requiring any extensive machining. The double feed, single stack magazine capacity was 30 rounds of .45 ACP ball ammunition. A magazine loader was issued to aid in loading the magazines.

After the M3 was in service for a period of time, the Ordnance Department felt that most of the problems with the weapon’s 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. This troublesome assembly would be completely eliminated in the improved M3A1 design. A new bolt was designed that was cocked by the finger of the operator. An enlarged ejection port was also needed to incorporate the new style bolt. The design also allowed for much easier field stripping by eliminating the need to remove the ejector housing in order to remove the bolt assembly from the receiver. The new model was standardized as the M3A1 December 1944. The M3 was then classified as Substitute Standard. The M3 and M3A1 were destined to completely replace the Thompson as the standard U.S. submachine gun, but by the time World War Two ended in 1945, not enough had been produced. Production was abruptly terminated in July of 1945 as the war was in its final days.

During the Korean Conflict of 1950 to 1953 the Thompsons and the M3 and M3A1 submachine guns were pulled from storage and sent to fight another war. By the time hostilities in Korea had ended, the U.S. was facing a shortage of submachine guns according to the peacetime requirements. The United States had provided an enormous amount of WWII weapons to South Korea as military aid during the war. In 1955 the Ithaca Gun Company of Ithaca, New York was awarded contract number DA-19-058-ORD-7854 by the Rochester Ordnance District to manufacture 70,000 M3A1 submachine guns. Production was halted after only 33,227 were produced. In the interim the United States had been searching for a new modern service rifle to replace the M1 Garand rifle. As a result of years of testing and evaluation the Ordnance Department adopted the M14 as the standard U.S. Service Rifle of the U.S. Army. The new M14 was to replace the M1 Rifle, M1 Carbine and the .45 caliber submachine gun. Due to a number of problems the first M14 rifles were not issued until 1959.

When the United States sent advisory personnel into Vietnam in the early 1960s, the troops were armed with many weapons from WWII. As the war endured, U.S. personnel were eventually issued M14, M16 and M16A1 rifles. On 11 December 1961, the United States began to supply an enormous amount of military aid to the South Vietnamese Government. Included in the aid were many World War Two small arms including 1919A4 – 1919A6 machine guns, BARs, M1 rifles, M1 – M2 carbines, and M3 – M3A1 submachine guns.

In order to keep the M3 and M3A1 weapons in serviceable condition during the Vietnam War, the production of spare parts was resumed. The Vietnam era parts will be stamped with only the Ordnance drawing number of the part. The letter codes GL indicating Guide Lamp, and the ITG code representing the Ithaca Company are absent. There was one insignificant change introduced during the Vietnam era, and that was the introduction of the chromium-lined barrel. The corrosion resistant chromium bore was implemented because of periods of extreme humidity and rainfall in the country. These barrels are easily recognized by the dull silver appearance of their bores and chambers.

Suppressed or “silencer” equipped versions of the M3 and M3A1 weapons were used by U.S. sniper teams in Vietnam to quietly dispatch any enemy personnel that might compromise their positions. These weapons were fitted with suppressors manufactured by the SIONICS corporation. A few suppressor-equipped grease guns were also used by the enemy in Vietnam. The enemy weapons used a suppressor that was very similar in construction to those made by Bell Laboratories for the Office of Strategic Services (OSS) during WWII. Since the OSS grease gun suppressors had no identifying markings on them, it wasn’t known for certain if the enemy suppressors were refurbished U.S. issue or Chinese copies. There was one internal difference noted. The enemy suppressors used oil soaked felt, original U.S. produced versions ones did not.

(Dan’s Note: There were a number of Special Operations personnel and others who have described taking an M3A1 Greasegun, and replacing the recoil springs with cut down M2HB springs- this increased the cyclic rate to around 800rpm, but was destructive to the rear end of the receiver).

A number of U.S. M3-M3A1 submachine guns were also captured and used against the United States forces and their South Vietnamese allies. The Viet Cong Guerrillas especially favored the compact and easily concealed “grease gun”. Communist China had supplied the Viet Cong and NVA troops with a substantial number of their own indigenously produced version of the M3A1. The Chinese copies of the M3A1 submachine gun were designated as the M36 when chambered for the .45 caliber cartridge and the M37 chambered for 9mm rounds. These two weapons were direct copies of “grease guns” that the United States had supplied to a desperate China during WWII. The weapons were very similar to the U.S. manufactured M3A1model except for the Chinese markings on the magazine housings.

The M3 and M3A1 grease guns are the only U.S. weapons adopted during WWII that continue to serve even today. Some weapons like the famous Thompson Submachine Gun endear, while others like the utilitarian M3-M3A1 grease guns simply endure.

This article was excerpted from the book The M3 and M3A1 Grease Gun. The book is available from Moose Lake Publishing 207-683-2959

By Robert Bruce

“The Marine criticism is even more harsh than that of the Army. From top to bottom, 1st Marine Division takes the dim view of this weapon; their experience with it during the Chosin Reservoir operation was the final blow to confidence. They want it either eliminated or made into a dependable weapon.” Operations Research Office Report R-13, Oct 1951

The compact, lightweight, semiautomatic M1 Carbine, born in 1941, had served the Marines reasonably well in the Pacific island-hopping campaign of WWII. The Army was generally pleased as well, although the “Baby Garand’s” lack of stopping power was one major factor in preventing it from replacing the .45 pistol as originally intended. So, what happened to destroy the little Winchester-designed rifle’s reputation in the Korean War? Selective Fire

Although the Army’s original specifications for what was to become the M1 Carbine called for semi and full auto capability, this last was dropped in the interests of simplicity and wartime pressure in order to field the maximum number in the shortest time. However, in 1944 when things began to look up for the allies, the first production-line full auto M2 versions began to reach the troops in Europe and the Pacific.

This was cleverly contrived so that only minor modifications were needed to the existing semiauto carbine to allow application of a few add-on parts. The most notable of these are the selector and the disconnector lever that, as long as the trigger is held back, allow the hammer to keep falling after each round is fired.

For whatever reasons, the best known official reports recapping weapons performance in WWII are not notably critical of the new selective fire carbine. Rather, they tend to list in general the whole family’s inherent shortcomings such as being about as powerful as a pistol and about as handy as a rifle. Not exactly a ringing endorsement….

Despite these and other problems the weapon was serviceable for its intended purpose and tremendous numbers had been produced of all versions including the folding stock M1A1 paratrooper model. Consequently, the postwar US Armed Forces had thoroughly integrated them into their small arms mix with particular emphasis on arming those troops whose duties are not primarily as riflemen. Notably, this included troops of artillery, combat engineers, signal and other supporting units.

“The carbine is a handy weapon for the individual whose duties take him to the line only occasionally, for rear area troops dealing with minor threats to their local security, and for minor escort and convoy duties where there is a danger of being jumped suddenly and at close range.” ORO-R-13

Reliability Problems

So far, so good, but almost as soon as the Korean War began reports of serious problems with the carbine started flooding in from Army and Marine units.

“Since being made full automatic, it is hyper-sensitive. In hot weather, even small amounts of dust and moisture together will cause it to misfire. In cold weather, it is more sensitive to frost than any other weapon, and more difficult to lubricate in such a way that it will remain operative.” ORO-R-13

The carbine’s catalog of Korean War woes goes on and on including lack of controllability in fast (750 rpm) full auto fire and feed problems with the relatively new 30 round “banana clip.” These blued sheet metal mags were also denounced for unwelcome contributions to chamber fouling caused by a tendency to rust at the feed lips so that crud would be dragged along with the ammo as the weapon cycled.

Perhaps most distressing is the carry-over of justified criticism from WWII experience denouncing the short rifle as underpowered and inaccurate at moderate distances. Numerous combat accounts provide chilling testimony to the lack of stopping power of the carbine’s puny110 grain full metal jacketed bullet.

“But the main reason my men lost confidence in the carbine was because they would put a bullet right in a Chink’s chest at 25 yards range, and he wouldn’t stop. This happened to me. The bullet struck home; the man simply winced and kept on coming.” 1st Lieutenant Joseph R. Fisher, 1st Marine Regiment (ORO-R-13)

Faint Praise

To be fair, there are also many instances on record attesting to the carbine’s combat utility. Interestingly, a number of those officers and men who gave the ORO task force some of the worst stories observed among their peers were themselves quite fond of their own “pet” carbines that were said to perform without problems. Perhaps they took better care or were just lucky to have particularly good ones. Also, many of the less fortunate troops interviewed would readily admit that the weapon was not intended to fill the role of the Garand or the submachine gun, but, properly maintained and used, served well on patrol and other situations.

Night Stalker

The small, light, handy carbine was a natural choice for Ordnance when the time came to field the infrared Sniperscope in quantity. This night vision weapon sight was based on the German “Vampir” (vampire) program, encountered in the closing months of WWII. Fortunately for our guys, this had been steadily developed in the years following so it was ready for issue in Korea where night combat with persistent enemy infiltration was the rule.

Because the range of this relatively primitive apparatus was limited to about 125 yards and its weight was a formidable 32 pounds, it made sense to use the carbine as its primary platform. As such, the selective fire M2 was chosen and modified by installation of a sight tube mounting bracket on top and attachment of a foregrip with switch assembly. Once these external changes had been made the carbine was then designated as an M3.

Although touted as equally useful in attack or defense, it is not surprising that the Sniperscope/Carbine combo showed greatest utility on forward observation posts where extra batteries could be stockpiled and a sandbag rest would be available. There, despite the considerable weight penalty and somewhat ungainly handling, its ability to pierce the blackest night to detect probing enemies was a godsend.

Primary References

FM23-7 and TM 5-9342

Brig. Gen. S.L.A. Marshall, “Commentary on Infantry Operations and Weapons Usage in Korea; Winter of 1950-51,” Johns Hopkins University, Operations Research Office Report ORO-R-13, Oct 27, 1951 Larry Ruth, “War Baby” Vol I and II, Collector Grade Publications, 1993

I spent some time looking at the tanks and the guns out front, but once inside I went almost directly to The Arms Room. A placard there states;

“One cannot understand military history without some awareness of the development of small arms—notably the rifle, pistol and machine gun.”

Specimens in the room give clear examples of that development. The earliest Arms Room exhibits date from the Indian Wars and the Civil War. World War I is well represented with German Maxims, British Vickers, M98 Mausers, 1903 Springfields and a Mauser Tank-Gewehr M1918.

World War II subguns on display include the British STEn, German MP40, U.S. Thompson, an M3, and a PPsh. The battle rifle case holds an M-1, an M1 Carbine, an M-14, a couple of M16s, two AKs, an RPK and a BAR. Single shot and bolt action rifles from America’s wars are also displayed.

Several pistols I saw were interesting and unusual. One, a 1911 with adjustable sights, was the “personal weapon”of Major General Chester J. Moeglein. Another Colt, a 1903 in .32 ACP, was also donated by General Moeglein. A Spanish pistol, an Astra 300 or a lookalike, was displayed too. According to the card it was not a simple semiautomatic pistol, but could be made into, “a rudimentary submachine gun.” The card also said the pistol was only produced from 1934 to 1936. Other pistols of note included a Nazi-marked 1910/22 Browning.

The museum is dedicated to preserving the military history of the State of Minnesota. Since the state has been involved in American conflicts since 1861, the exhibits also give a good history of America’s wars from then until now. Minnesota also has quite a record of military firsts. Museum Director David L. Hanson, Colonel USA Retired, ran down the list for me in an interview at the museum.

Minnesota was the first state to provide militia troops to Lincoln’s army in 1861. The first armor unit deployed for World War II was the 194th Tank Battalion from Brainard. It was sent to the Philippines in 1941 and was involved in fighting the invading Japanese army in a delaying action before the Philippines fell. Many of its men were on the Bataan Death March. On November 19, 1943 the first shell fired by American ground forces against the Germans was fired by Battery B, 175th Field Artillery Battalion of the 34th Infantry Division of the Minnesota National Guard at Medjez-El-Bab, Tunisia. Members of a Minnesota Naval Militia unit crewed a deck gun aboard the destroyer USS Ward. An hour before the attack on Pearl Harbor, the Ward and the Minnesota gun crew fired the first shot against the Japanese in Hawaii, sinking a two-man Japanese mini-sub that was trying to enter the harbor.

The museum also has material on General John W. Vessey, Jr. He enlisted in the 34th Infantry Battalion of the Minnesota National Guard in May of 1939, and received a battlefield commission at Anzio in 1944. After World War II, he stayed in the army and rose to wear four stars. He became Chairman of the Joint Chiefs Of Staff in June of 1982 and served in that position until October, 1985.

Exhibits, which include correct firearms and equipment for the times, cover The Indian Wars, The Spanish American War, World War I, World War II, Korea, Vietnam and Desert Storm. My wife and I thought the exhibits were well designed. Our kids are still a little museum-resistant after a family trip through Wisconsin, Minnesota, the Dakotas and a little of Montana two years ago. Say “Buffalo Hide Scraper made from a rifle barrel,” and they cover their ears and wail. All three of them—17, 15 and eight—seemed to have a good time at the Minnesota Military Museum. It didn’t hurt that there were no hide scrapers displayed, or that climbing was allowed on the tanks outside the museum.

Director David L. Hanson, Colonel USA Retired told me that the museum, “caters to the tourists during the season.” It is open from 10 a.m. to 5 p.m. Wednesday through Sunday from late May to early September, but closed on National Holidays. The rest of the year it is open Thursdays and Fridays from 9 a.m to 4 p.m. Tours for groups may be arranged by calling ahead. The suggested donation is $2 per adult with military personnel and children admitted free. Annual memberships start at $18. The Museum can be reached at (320) 632-7374, or by mail at Minnesota Military Museum, Camp Ripley, 15000 Hwy., 115, Little Falls, MN 56345. The email address is mnmuseum@brainerd.net., and there is a also information available on the Web through the Explore Minnesota website.