At the beginning of 1967, the Vietnam War was escalating and defense industries were responding to the military’s need to counter an increased enemy threat. Numbered among the most effective and reliable systems were the various Gatling guns produced by the General Electric Armament Systems Division in Burlington, Vermont. The war brought on an ever increasing demand.

GE weapon systems at that time were designed around two Gatling guns: the 20mm M61 and the 7.62mm Army M134 also designated by the Air Force as GAU 2B/A Minigun. Both guns and ammunition handling systems were being produced in record numbers. Internal installations of the M61 were found on most fighter and attack aircraft and a few bombers. The F4 Phantom aircraft had no internal gun systems and relied on the SUU-16 and newer SUU-23 gun pods for strafing and close combat encounters with enemy MIGs. Miniguns were finding application everywhere. Pods, helicopter pintles and internal aircraft applications were all being manufactured along with a module system used for side firing these guns from AC-47 cargo planes – a deadly system nicknamed “Puff the Magic Dragon.”

On January 3, 1967, the Monday following a huge weekend snowstorm, more than 100 new employees waited patiently outside the GE plant while the guards arranged for them to be escorted to security processing and orientation. GE desperately needed inspectors, machinists, secretaries, engineers, and other workers to support new production. Fresh out of engineering school, I waited with them, anxious to get started on my first real job.

Soon after their employment, every employee in any way involved in design or testing was made aware of the most important design secret responsible for the success of these weapon systems. That secret was Round Control. GE guns were like no others. Rounds were not fed by being launched into free flight with hopes they would find their way into the chamber. There were no fired cases or links propelled by springs or ejected out of gun receivers by impact. GE guns and ammunition handling systems always had 100% complete control of the round, the fired case, and if there was one, the link. Every round transfer, every link movement, every round transport had to be under complete control at every position in the weapon cycle. Springs were permitted in these systems but were never used for positioning of rounds, cases or links.

Achieving round control in these designs was a costly and labor intensive process. In the earliest stages of design, a layout was prepared by highly skilled draftsmen, called “designers.” On their layouts, silhouettes of rounds, links, or fired cases, (appropriately called “paper dolls”) were moved to every position through the system to determine if control was maintained throughout the cycle. After the first prototype was built, technicians and engineers went through a similar ritual by moving dummy rounds through the system. Dummy rounds were rotated through the sprockets and passed by round guides to see if one could be forced out of control, or moved into a lock-up position. They tested for any condition that could potentially jam the system. Evidence that control could be lost was cause for a redesign and retrial. No live firing was permitted until these design flaws were corrected.

During these trials, it was inevitable to find some obscure sequence of events that might cause a round or case or link to be coaxed into a position where a jam or loss of control was possible. A debate would ensue. Could this bizarre sequence ever really happen? Was it worth the risk or would it be wise to modify to the design? In the end, the older, experienced heads would prevail. Appropriate changes were made and retested. Inspired by Murphy, GE had a corollary to the Round Control rule: In a gun system, if it can happen, it will. After the hand cycling system testing was demonstrated to keep good control of the ammunition, it was time to move out to the firing range.

At the range, company photographers trained 16mm Fastax cameras on various parts of the system to see in slow motion, what happened when the gun was fired. Depending on the camera model, the rotating mirrors in these Fastax cameras captured motion at a rate of 5,000 to 16,000 frames per second. After a lengthy development process, the films were reviewed on special motion analysis projectors that permitted frame counting – a feature that enabled engineers to estimate the speed of the moving parts they were observing. It was always amazing to study these films. Steel parts and tightly bolted joints seemed to move as if they were made of rubber while traveling waves ran back and forth in the springs making some parts of it extend while elsewhere adjacent coils crashed into each other. Camera set-up and filming of weapon systems was time consuming and costly but was one of the only ways to indicate problems that would have gone unnoticed until a part failure or jam occurred. High speed photography was another one of the GE secrets used in the development of reliable weapon systems and was an invaluable tool in figuring out the cause and corrective action of feed jams – appropriately called “wrecks.”

Before the development of a new Gatling gun could begin, some important design parameters had to first be decided. The maximum rate of fire achievable was fixed by the length of the round, the pressure characteristics of the ammunition, and the number of barrels. One important design parameter resulted from a decision on how the weapon would be cleared at the end of a burst. The intensive heat developed in the barrels during firing would quickly rise to a level that would cause a live round to detonate shortly after it entered the chamber. Gun powder only has to reach around 330° F before cookoff becomes a problem. Cookoff is a safety issue that cannot be tolerated and it was up to the design engineers to figure out how avoid it. GE had a simple rule: no matter how it was accomplished, at the end of each burst, all barrel chambers had to remain free of live rounds.

There were various ways to clear a Gatling gun and each one had advantages and drawbacks. Designers of the first modern Gatling gun, the 20 mm M61, solved the problem by allowing the gun bolts to cycle through a second, alternate cam within the main housing. The primary cam moved the gun bolts fore and aft so the weapon would fire as the barrels rotated. A second cam held all the bolts to the rear, in clearing mode, so rounds being fed simply went into the gun and came out without ever being fired. A solenoid actuated switching cam determined in which cam the bolts would travel. This hold-back clearing method was simple and effective but was not popular on the battlefield. In the 20mm gun pods, SUU23 and older SUU16, hold-back clearing dumped 6 to 8 live rounds overboard each time the pilot released the fire button. When dropped over Vietnam, they could be picked up by NVA or Viet Cong who used them as a principle ingredient for booby traps. Their electric primers were easily detonated with a common battery.

The 7.62mm Minigun used diversion clearing that was almost the same as hold-back clearing; only it happened a little earlier in the feed cycle. As soon as the gunner let off the trigger, the gun feeder would divert live rounds overboard so they would not be fed to the gun bolts. This system had the advantage that it didn’t require an expensive, separate cam path in the main gun housing like the M61 to keep the bolts to the rear at the end of the burst. Like holdback clearing, the rotating barrels and rotor could coast to a stop without stressing the system. The disadvantage was the same – more rounds carried out to the battlefield that never got fired.

Some of the helicopter gun systems and eventually the Minigun system used a declutching feeder for clearing. The declutching mechanism was located on one of the sprockets feeding the weapon. The principal of operation was simple: when the sprocket turned it fed rounds when it stopped turning it didn’t. The sprocket was connected to a series of rotating knife blades and a solenoid activated clutch that caused the feed sprocket to stop and start.

The advantage of the declutching feeder was that it didn’t dump any live rounds overboard and left the chambers clear of live rounds after each burst. The disadvantage was that when the feed was declutched, the gun system spun free to wind down, but the entire feed system including links and ammunition was forced to come to a sudden halt. Consequently, this method could only be used on lower rates of fire since at full rate, 6,000 shots per minute, the knife blades and other parts would eventually self destruct.

The achievement of 100% round control would not have been possible without another GE secret, the linkless feed drum ammunition handling system. Here was a system that allowed for the efficient storage of ammunition in the airframe capable of reliably feeding ammunition at 6,000 shots per minute. To the relief of ground troops, the “double ended” linkless feed system retained all fired cases and unfired rounds within the system rather than releasing them overboard.

The linkless feed system may someday be remembered as one of the most ingenious article storage and delivery systems ever designed. The workings were simple, but the design and execution was complex. The basis for the system is a drum with longitudinal retaining tracks that engage the rim of the round for control and allows the rounds to travel along the rails.

A sheet metal auger, called the helix, works as a screw conveyor to push the rounds along the tracks as it turns. Follow the path of a round in the figure as it makes a complete cycle through the system. Beginning with the round labeled “Round A”, as the drum helix turns it augers all the rounds in the drum toward the exit. When “Round A” reaches the end of the feed drum it is plucked out of the retaining tracks and moved by the scoop disc sprocket. It is then placed into a rotating ring that has retaining tracks that constrain the round longitudinally by holding it at the case rim. At this point, it’s important to note that the drum helix is really a double lead helix; meaning that at the same time “Round A” reached the scoop disc sprocket, another round reaches a second scoop disc sprocket located 180 degrees away. Both rounds enter the retaining ring at the same time, and rotate around with the retaining ring until they are picked out by a sprocket in the drum exit unit. The drum exit unit places each round into a conveyor bucket called a “conveyor element.” The conveyor elements are linked together and constrained to work in flexible chuting – a semi-flexible channel that keeps rounds or fired cases under control as they are transported.

After “Round A” reaches the gun feeder it is picked out of the conveyor element and fed into a gun bolt through a series of feeder sprockets. Another secret of the GE designs is that when rounds are transferred from the control of one sliding or rotating member to another, the transfer must take place with both devices moving at the same speed. For example, feed sprockets must accelerate rounds to match the speed of the faster-moving gun bolts. Conversely, fast moving fired cases are slowed down after they leave the gun bolts to match the velocity of slower-moving conveyor elements.

At the gun/feeder interface each round is precisely fed into in the fixed extractor of a gun bolt so the bolt can chamber and fire the round. After being fired, “Round A” is now depicted as “Fired Case A” in the figure and is extracted by the rearward-moving gun bolt. “Fired Case A” passes through the unload sprockets on the opposite side of the feeder and is decelerated to match the speed and spacing of the conveyor element. The moving conveyor transports “Fired Case A” to the back side of the ammunition drum where it is picked out by the Drum Entrance Unit. Hereafter it is transported by components identical to the exit side of the drum, “Fired Case A” is returned to control of the drum helix and finally reaches the point where it started through the system as “Round A”. The linkless feed system goes from completely loaded to completely empty as rounds are fired by the gun system. Round control reigns as king in every transition and along every inch of conveyer, through the gun and back into the feed drum as cleared rounds are placed back in the drum.

Through much of the 1960s, helicopter and fixed wing systems were armed with the 20mm M61 Gatling gun that still used linked ammunition handling systems. Linked belts of ammunition were simply pulled from a box and into a feeder where the link was stripped and the round fed, as always, under rigid control. As long as every round was properly linked with every cartridge rim properly seated in the link detent provided for that purpose, life in the gun system was good and reliability could be maintained at a high level. But every now and then, somehow back at the ammunition factory where the belts were initially linked, a round could be linked “long”. The case rim was forward of where it should have normally been causing the projectile of the long round to stick out from the belt about 1/4 inch higher than the rest.

Unfortunately, accommodation of this condition was overlooked in the original design of the feeder. When the long round entered the feed sprocket the case rim went over the top of the rim guide instead of being properly engaged by it. The round would pass through the feed sprockets long and instead of this feeding round being engaged in the fixed extractor groove in the gun bolt, it was fed out ahead of it. The round was pushed forward by the bolt, chambered, crushed a bit by the extractor, then was left in the chamber as the bolt drew back. Since the bolt extractor was not engaged with the case rim the round could not be extracted. The fun really started when the next round was fed into this bolt. The incoming round came forward and found the long round already chambered. The hydraulic motor powering the system didn’t know or care that two objects were now trying to occupy the same space and the bolt came grinding forward to create a surreal union of these two rounds. Detonation was possible and wreck of huge proportions was assured. In the aftermath the remains of the two rounds, properly de-activated, made an interesting artifact for an engineer’s desktop as an inspiration to develop a means to prevent this occurrence.

Eventually a clever engineer figured out the cure for the long round malady. It was out of the box thinking that made GE world famous in gun design business. What did he do? It was surprisingly simple. He merely redesigned the feeder so that every normally linked round was pushed forward to become a long round and then he positioned the rim guide and all of the other components for proper feeding and engagement of what were then all long rounds. Should an improperly linked long round ever come along it simply didn’t get pushed forward since it was already in position to feed normally: and it did.

The engineering time required to lay out a complete gun and ammunition handling system was very long and laborious, but GE did it right. Engineering designers working on drafting boards made layouts showing different views of all connecting and related parts. Engineers worked with the designers making tedious slide-rule calculations and laboratory tests with bread board and brass board models to verify the integrity of the design. When the design team was happy with the job they held their first design review, passing out copies of the design layouts to a review team of engineers not associated with the program. There were several design reviews held throughout the development phase of the system with a formal design review required before full scale production could begin. Their purpose was to root out any obvious or not so obvious errors to be corrected before proceeding to the next stage in the development. With so much brain power in these meetings, it was not uncommon that major design improvements were often suggested, resulting in an even better system.

The design review team was relentless. After determining the design met the basic design criteria, they dug deeper: Could any parts be assembled backwards? Could disassembly assembly be done safely and with common tools? Were chamfers put on parts to aid in assembly? How were threaded fasteners kept from loosening? Were the hardness levels appropriate and did the design team make sure that parts of the same hardness did not slide against each other – a design subtlety found in the best mechanical designs? The design team was given a list of action items for design remediation and a redesign effort took place followed by the final design review. Only after proper corrections, testing and reviews were completed would there be approval to commit the design to production.

When a design was finally approved for production, a team of draftsmen and drawing checkers would be assigned to make the final drawings and parts lists. It was these individual part drawings making up the Technical Data Package (TDP) that played a major role in the success or failure of any design. TDP drawings were used by the Production Department for the manufacture of parts, and were the documents to be sent out to vendors of springs, castings, forgings, and other procured items. Intensive studies were undertaken to make sure that the tolerances – maximum and minimum dimensional extremes of every feature of every part would always produce components that worked together without interference at one extreme or excessive play at the other. Tolerance studies were expensive and time consuming but uncovered potential problems that, if overlooked, could turn a great design into an awful one.

Before any drawing would be released for production, the responsible draftsman sat with an experienced manufacturing engineer to review the manufacturability of the part and to establish what are known as datum planes. Datum planes are used in manufacturing to orient the part in the x-y-z planes. In general, three datum points or “targets” on the part specify the principal plane, restraining the part in the X direction, two datum targets specify how the part is held in the Y direction, and a single target is all that is needed to restrain the part in the Z direction. When the part is positioned for manufacture it is held in a fixture that touches on the datum targets. The Quality Control department uses these datum targets too, positioning the component by these targets in order to inspect the part the same way it was manufactured. It may appear odd to applaud something as obvious as this, but surprisingly few manufacturers do this and worse yet, they’re surprised when their parts don’t measure up. But GE knew how to do it right and it was another secret to their successful designs.

When the draftsmen met with the manufacturing engineer to establish the datum planes and targets, it was not uncommon for them to be in conflict. After all, the designers knew which dimensions were important to the design and had their own ideas on how the parts should be held. The manufacturing engineer, on the other hand, had the last word on how the parts would be manufactured and established the datums based on ease of manufacture. Their conflicts were known to GE management and purposely overlooked. In today’s advanced managerial courses, managers are taught that not all conflict is bad and properly handled can be a driving force for improved performance. Accepting that the manufacturing engineer had the final say, the draftsmen would think through the manufacturing of the part and establish datums and datum targets at points that made good manufacturing sense to them. In time, most of the draftsmen got so adept at this that the manufacturing engineer would only make few, if any, changes to the first draft, saving everyone time and GE money.

After guns systems were built they were trucked out to the Underhill Range, a government facility that was managed by GE. Here the systems would be bolted to the floor of a three sided weapons bay so the guns could be fired and measurements taken of accuracy, power consumption, and rate of fire. All firing was done from behind a reinforced door since wrecks and cookoffs were extremely dangerous. It should be noted that even though the gun was designed to be empty at the end of a burst, an unplanned stop in the cycle caused by a wreck can leave a live round in the chamber.

Today, companies tout their certification with the International Standards Organization (ISO-9000 or ISO-9001) to assure their customers that they are following strict quality control standards. Predating ISO was the U.S. Government quality standard Mil-Q-9858 that was enforced along with a host of other guiding military specifications. Adherence to specifications under the watchful eye of an in-house U.S. government inspector became yet another reason for the success of these systems.

In the peak and latter years of the Vietnam War, the dedicated men and women of the General Electric Company Armament Systems Department worked tirelessly to consistently produce the finest, most reliable gun systems in the world. These were built to support American and allied fighting forces, yet almost daily these employees would be subjected to insults, heckling, and even threats from war protesters who paraded back and forth in front of the factory in organized demonstrations.

The GE Armament Systems Department was eventually sold to Martin Marietta and later to General Dynamics (GD). Today GD finds that they can do the same work with fewer employees due to the major strides made in computer aided engineering, computer aided manufacturing, high speed videos, and advances in computer numerical controlled manufacturing and inspection. With more modern equipment, GD still designs and produces advanced weapons and ammunition handling systems. Most of the Vietnam era employees retired long ago, but not before the design secrets had been passed along. GD continues to produce weapons with enviable reliability records and is well known for their expertise in the field of weapon system development.

Since the mid 1960s, the Minigun has been much more of a star on the battlefield as it has on the silver screen. With its distinct sound and enormous rate of fire, it is immediately distinguishable by all within even a remote proximity. It has been over 40 years since the lore of “Puff the Magic Dragon” began, and with modern technology assisting in fine-tuning this incredible weapon system even more, it appears that it is here for many more years to come.

Capable of firing in excess of 6,000 rounds per minute and designed after the M61A1 20mm Vulcan, the Minigun can inflict a devastating amount of damage in a minimal amount of time. With several rate of fire settings depending upon the model and manufacturer, there is no question that firing up to 100 rounds of 7.62x51mm NATO (.308 Win) per SECOND, for several seconds, has the potential to eliminate whatever immediate threat is being targeted. While some believe that more is better, the engineers at Garwood Industries have other ideas.

Garwood Industries of Scottsdale Arizona is a certified government contractor specializing in the design and manufacture of Miniguns. They have been studying the Minigun design for some time and have developed their latest project, the M-134G, which incorporates several upgrades to the original G.E. system designed over 40 years ago. Through their extensive research they have discovered that the highest rate of fire the system is possible of operating at may not be the optimum rate of fire for hit potential. After several extended firing exercises, Garwood collected enough data to conclude that the optimum rate of fire for the Minigun system is approximately 3,200 rounds per minute (rpm). This cyclic rate provides the operator with the maximum amount of target saturation while expending a minimum amount of ammunition. Even a novice gunner can achieve a greater rate of accuracy at the 3,200 rpm mark. Because of these findings the M-134G is being produced and offered with this firing rate as well as 4,000 rpm and the previous standard of 3,000 rpm.

While the rate of fire research and adjustments have been quite significant, several other upgrades and improvements have been implemented by Garwood Industries, and for the first time since General Electric manufactured Miniguns in the 1960s, the complete M-134G system is being manufactured to meet and exceed military requirements. To accomplish this, all of the weapons components adhere to ISO standards to ensure quality traceability.

A Brief Tour Inside The Minigun

The differences in the M134G are numerous and maybe even slightly confusing unless you are intimately familiar with the method on which the system functions. Everyone knows the barrels spin and it shoots fast but beyond that, the details start to depart from traditional firearms mechanisms quite fast. In order to learn about the system upgrades, let’s first look at how the system actually functions. (For a very detailed look inside the Minigun and how it works, see Small Arms Review Vol. 5, No. 7, April, 2002)

First, it is important to know that the system is operated from an outside power source and not dependant upon ammunition ignition or produced recoil of any kind to function. In the case of the M-134G this power is supplied by an improved 28 Volt DC motor.

In the most simplistic terms, the Minigun is a single group of 6 complete guns working in unison as a single gun. This takes place inside a single “receiver.” In the M-134 system there are 6 barrels and 6 complete bolts and bolt carriers, each containing a firing pin and spring. Each bolt also has a cam bearing which guides it along a cam path inside the receiver.

To follow a single round through the entire mechanism it would take this route: Linked with several other rounds, life starts in an ammo box and proceeds through a feed chute into the feeder/delinker. As the main drive (powered) gear rotates, it spins the entire rotor mechanism turning a parallel gear to the rear of the rotor. This gear engages the feeder/delinker gear and pulls the linked ammo up the feed chute and into the gun. As the feeder/delinker rotates, a set of cam bearings (similar to those on the bolts) and attached to feeder push rods, follow another spiral cam path and progressively push the rounds out of the links at the prescribed time in the rotation. The stripped rounds are pushed into the feeder wheel and continue to rotate until meeting the counter-rotating rotor mechanism and fed into a corresponding bolt face with the assistance of the guide bar, or “hand-off” as it is sometimes referred to. The round travels in the bolt (which is following its own cam path via the bolt cam bearing) until reaching the correct position where the bolt is locked and the round is fired. As the rotor continues to rotate, the bolt is unlocked after firing and the fired case travels to the ejection position where it is assisted in ejection by the guide bar.

Other parts that may be referred to when discussing the function of the Minigun include the clutch assembly, the booster assembly and the safing sector. The clutch assembly is utilized in conjunction with the feeder/delinker. The function of the clutch is to almost immediately stop the gun from firing when the fire button is released without dumping live rounds into the expended brass pile. This is accomplished by stopping the feeder/delinker functions and booster assembly simultaneously.

The booster assembly is the mechanism that assists in feeding the Minigun. In belt pulls of over 8 feet in height and greater, a stretching or stressing of the links can occur from the weight of the belt, combined with the speed in which it is being pulled. If this happens the belt can break or the stretched links can create a jam. In essence, the booster pushes the ammo up from the source and works to lighten the load on the feeder/delinker. The belt “push” rate of the booster assembly must be timed exactly the same as the belt “pull” rate of the feeder/delinker to avoid other feeding problems such as jamming, binding and belt breakage.

The safing sector is essentially an access door which when opened, interrupts the bolt cam path in the receiver, and prevents the gun from being fired. When open it also allows the removal of the bolts.

The Garwood Upgrades

Now that we have a basic understanding of the operation of the gun and its components, we can get a little deeper into the improvements offered with the M-134G.

• The Drive Motor – Many positive improvements to the tried and true General Electric drive motor have been implemented using products not previously available. These improvements allow the motor to be lighter and extend the service life at the same time. Since the beginning of the M-134G project, three proactive upgrades have been accomplished and even the solenoid has been revised several times.

• Fire Control Unit – Garwood Industries has upgraded the fire control unit using state-of-the-art electronics to guarantee unsurpassed reliability not previously thought possible. A manual override for the booster assembly is standard on all M-134G models.

• Feeder/Delinker – The Garwood feeder/delinker has an upgraded cartridge handoff system and has been finished with a new high-performance coating that will increase longevity and enhance operation in all environments.

• The Barrel Cluster Assembly – The barrel cluster assembly has been re-engineered to both lighten the weapon system and improve performance. The newly designed flash suppressor completely eliminates the blinding flash that was a constant problem with older Minigun systems. New designs are being tested to even inhibit the sparks that are created from unburned powder and it is expected to completely eliminate the visual signature under fire.

• The Bolts – A new government model is being finalized that utilizes a new proprietary bolt design. The material and coatings used in this latest system greatly improve the longevity of the system and exceed current specifications.

• Grip Assembly – The M-134G spade grip assembly is integral with the receiver through a new proprietary mounting lug. Previous versions only mounted to the clutch or other components. The new mounting area greatly improves the rigidity of the system.

• Rail System – The M-134G incorporates a rail system that allows the easy mounting of several accessories that may be found useful to its operator. These include, but are not limited to, scopes, electronic sights, lasers and spot lights.

Torture Testing & Range Time

Some ideas look great on paper and even make sense under controlled environments, but don’t necessarily make the grade in real world situations. Because of this, torture testing is an important part of the Research & Developmental phase for proving any new weapon system. Shooting massive quantities of ammo is a very legitimate and serious part of the gun industry to determine what, when and if parts fail.

In 2006, Garwood Industries fired over one-half-million rounds during the torture testing phase of one of the earliest guns. During the entire series of tests there were zero recorded failures of any major components. Throughout the whole test cycle only minor pins and springs required occasional replacement, much to the satisfaction of all principals and engineers involved.

The time spent live-fire testing the Garwood M-134G Minigun was as educational and interesting as it was enjoyable. This writer was accompanied to the range by two of Garwood’s major principals, Tracy Garwood and Randy Myers. Tracy and Randy are both extremely passionate about their product and both are a wealth of information pertaining not only to their particular system, but with the entire history and development of the Minigun since its inception. Both are enthusiastic and happy to share their knowledge with anyone who is interested in educating themselves about it.

Range time was spent in the Nevada desert and since we were so close to Las Vegas, we were provided with an original military H1 Humvee for use as a rolling mount by Long Mountain Outfitters, LLC. We were also allowed access to their classroom facilities to disassemble the M-134G and take the studio photographs that accompany this article.

The live fire exercises went off without a hitch. The operating speed during testing was in the 4,000 rpm range and the ring mount contained every bit of the 375 pounds of peak thrust from the recoil, and allowed the shooter to focus on shot placement. A bright laser was used as an aiming device, and the hail of lead to follow the green dot in the impact area was a testimonial to the effectiveness of the system. The only glitch we encountered was when we were shooting without the assistance of a booster assembly and we got a bit overzealous with the hanging length of our belts. A broken link was quickly removed and we were back under way.

Conclusion

This writer has had the opportunity to fire several Minigun systems and it remains a thrilling experience every time. As exciting as it is, having the opportunity to get inside and really digest how the new upgrades work in conjunction with one another was equally as stimulating. The Minigun is a weapon system unlike any other, and the opportunity to intimately study and build a better understanding of it is not taken lightly or without appreciation. In every conversation with Tracy and Randy about this project over the last few years always brings a newly found excitement and enthusiasm as more upgrades are discovered or new test results are recorded.

After talking at length about manufacturing and production capabilities, most of my questions about current or future military use were answered without having to ask them. While we were going over some of the technical specifications of the system, Tracy received a private phone call that had him smiling from ear to ear. He had to excuse himself for a few minutes to wrap up an order for a 40 gun Helicopter Gunship deal they had been approached about earlier. It looks like the Garwood M-134G is going to be around for a while.

Garwood Industries P.O. Box 15393
Scottsdale, AZ 85267
Phone: (800) 464-1892
E-mail: sales@garwoodindustries.com
Website: www.garwoodindustries.com

Q-Regarding the Suomi M31, I have studied the trigger mechanism, and it has a full auto, a semi auto and a safety position. Safe blocks the trigger from moving and Full Auto raises and lowers the sear as the trigger is pulled. That makes sense, but the Semi Auto sequence has me confused. In this mode, the whole sear is initially pulled down and then is released upwards. I do not see how this reengages the rear safety sear. A detailed sequence of firing description, or pictorial might be very interesting to me, and some readers unfamiliar with the working of the Suomi.

A- The Suomi submachine gun is a very reliable design, and quite desirable for collectors and shooters in the United States. John Ross was well known for shooting trap with a Swedish M37/39 and 9mm instant light tracer at Knob Creek, which showed just how controllable a submachine gun the Suomi design is.

The Suomi design utilizes an early form of disconnector in the semi auto mode, and it sounds like you are looking at a trigger pack and trying to figure out how it works – because outside of the system, it doesn’t. There are other factors that you need to see in order to make the Suomi disconnector seem sensible. A photo sequence is probably the best way to illustrate this.

Q-A long time ago, I bought a parts set from you for the Beretta M57 submachine gun. I have been waiting a long time for a write up in SAR, but can you at least give us some information on the magazine in the system? The one I got appears to have been “made up.”

A- That was a long time ago. And, yes, the magazine we had with the kits was “made up.” The Beretta Model 57 submachine gun was a cross between an M2 Carbine and a Beretta dual trigger submachine gun. While the M57 is outwardly very much like an M1 Carbine, and many people bought those kits because they collected M1 series guns and thought this to be the ultimate oddity, it is most decidedly not an M1 variant. I plan a feature on this system at some future point, but a bit of information might help. While also similar to and often mistaken for the San Cristobal carbine, the M57 is even rarer than that. We had only been able to track manufacturing of about a thousand of the M57s, and LMO obtained 135 parts sets from North Africa back in the late 1980s. Unfortunately, when they came in, the magazines that came with them were for the San Cristobal Carbine and did not go with these kits at all. Master Gunsmith Stan Andrewski made enough magazines out of M1 Carbine mags so that each kit could have a magazine, but these were obviously not original to the weapon.

The Beretta M57 submachine gun utilizes a dual column, dual presentation, straight bodied, steel magazine. Caliber is .30 Carbine. These are similar to the San Cristobal Carbine or US M1 Carbine magazines, but not interchangeable.

Q-Are there any Australian F1 submachine guns in the United States?- email

A- I would have to assume you are asking if there are any fully transferable or dealer sample F1s in the US, and would have to say that I have never seen one. I spoke with a few other long time dealers and collectors, and they had not run across one either. There are a few in the government museum collections. This odd submachine gun appears to be a cross between a Sterling and an Owen, but is in a class by itself. The top mounted magazine allows for getting close to cover when firing, and it is internally similar to the Sterling. These were all made at the Small Arms Factory in Lithgow, New South Wales, Australia, and the production started with the X3 submachine gun and continued through the Mid 1960s as the F1. These were used by the Aussie troops in Vietnam, so it is very possible that an American GI brought one home and registered it in the 1968 Amnesty. If anyone has any information on these in the US, it would be appreciated by SAR’s readers, so please send it in.

Q- A friend said he had a “Stinger” 22 and that it didn’t need registration. It was clearly a pen gun, and not one of the fold down Stinger pistols that have been legally sold as handguns. Any truth to that?

A- Hard to tell without a photo from you. I suspect you are referring to the “Clandestine Weapon, 22sht”, more commonly referred to as the “OSS Stinger”. This was designed in 1943, and only a few thousand of these single shot, non-reloadable, throw-away weapons were made. Once fired, they are not considered a firearm. If it is still loaded, it is considered an Any Other Weapon, requiring registration with NFA Branch of ATF. In other words, if it is live and it isn’t registered, it is contraband. Expended (fired), it is nothing but a curiosity. Here is a photo comparing the OSS Stinger to the MAC Stinger, which was a 1960s design that was reloadable. These MAC Stingers are all considered to be Any Other Weapons requiring registration and transfers under the National Firearms Act.

Q-I have a friend who says the Russians are using Miniguns on their helicopters, and I wonder if the US is supplying these, or are they making Miniguns in Russia now?

A- The US manufacturer is not supplying M134 Miniguns to the Russians. They have their own design and have had it for some time. It is called the YAK-B, and it is very different from the US Minigun. The YAK-B is a four barreled gun, usually in 12.7x109mm (same as the DShk38/46 ammunition) and sometimes it is offered in 7.62x54R, although I have never seen one in this caliber, anywhere. The beauty of the Russian design is that contrary to the complex receiver made for the US M134, the YAK-B is simply a length of tube that has bolt in cam paths that can be changed if worn. This greatly simplifies manufacture and rebuild, and the bolts have large, effective rollers on them. Inside the barrels is an energy storing spring, and there are blank firing cartridges that can be fired to get a stopped gun moving again. SAR is planning a feature on the YAK-B system, but here is a picture of the 12.7 YAK-B next to a 7.62x51mm M134 Minigun system, which is the US Minigun you are referring to.

Send questions to: Raffica
sareview@aol.com
Or mail to Small Arms Review Attn Raffica
631 N. Stephanie St #562
Henderson, NV 89014