Right side view of the experimental French made Gevarm .22 Automatique Carbine. This rare specimen fires from the open bolt and takes either the 8 or 20-shot magazine shown with the gun.
By J.m. Ramos
For military weapons enthusiasts, rimfire full auto guns are considered a rarity. They exist either in prototype form or as a limited production class. Most notable among the limited production model is the famed American 180 submachine gun. Prototype and experimental firearms are a more fascinating study as the inventor or designers themselves put a lot of effort in creating them from scratch to a workable stage. Particularly of interest are those rimfire guns that are capable of selective fire operation. They are more complex and sensitive in their working mechanism than their big bore counterparts. This is due primarily to the type of ammunition used and the size of components being utilized in order to function with the diminutive rounds. For modern weapon inventors and designers, creating a trouble-free full auto .22 rimfire is quite a challenge. They get dirty quite easily and the shell is so thin that rim ruptures often result with the gun discharging during bolt-bounce. Bolt bounce is best described as a very slight gap between the chamber mouth and breech face. This occurs immediately after the bolt face hits the chamber mouthduring forward recoil. With submachine guns utilizing center fire pistol cartridges and operating on blow-back principle, bolt bounce normally does not occur since the bolt is much heavier and the recoil spring is stronger. Submachine guns utilizing a built-in fixed firing pin on the breech face like the Sten, UZI, Ingram and M1 Thompson, fires before the breech hits the chamber mouth. This is normally termed as advance primer ignition and works quite well because of the much thicker wall of the center fire shell and rim.
Barely any .22 self-loader will pass the 500 round mark without malfunctioning. The main culprit is normally the chamber getting excessively clogged and dirty with built-up powder and lead residue after several hundred rounds fired. Malfunctions will soon occur as the breech face and feed ramp also becomes excessively caked. The cycle of the bolt will soon become erratic and will no longer work in harmony with the feed timing of the top round from the magazine. Despite the advancement in weapons manufacturing technology today, many .22 self-loaders in the market still jam from the first time a fully loaded magazine is fired until the so-called break-in period has passed. The weapon described in this article is so designed that the above noted problems relating to rimfire automatics has been virtually overcome.
Back in the late 1960s, the late John Minnery acquired an experimental selective fire .22 rifle from a former Gevelot Canada employee who brought the weapon to a military gun show at Ancaster Fairground in Ancaster, Canada. Gevelot was the primary importer of the French made Gevarm .22 semi-automatic rifles in North America back in the 1960s. This particular weapon was the first full-auto gun in Minnery’s collection of rare and prototype exotic weaponry.
The 1960s saw the resurgence of sporting arms import in the North American market from many well known European manufacturers like Mauser, Walther, FN, SIG, Beretta, Luigi Franchi and Heckler &Koch. Along with the big names came the little known company Gevelot, a French ammunition manufacturer. Sometime in the late 1940s, numerous French arms companies undertook weapons development programs with the hopes of gaining a military contract from the French government to replace their obsolete underpowered submachine guns produced during the German occupation in WWII. The MAS Model 1938 was chambered for the French 7.65mm long. A 9mm version was introduced in 1947. This model wastested by the French army but was not adopted despite the many unusual features and more powerful 9mm Parabellum chambering. In that same time period, other French arsenals like Manufacture Nationale d’Armes de Saint-Etiene (M.A.S.), Manufacture Nationale d’Armes de Tulle (M.A.T.) and the Paris based private firm of Hotchkiss introduced several interesting submachine guns of original design for the same purpose. Gevelot introduced the Gevarm Type D-3 (fixed wooden stock) and D-4 (telescoping metal stock) submachine guns. Both weapons were chambered in 9mm and fired on the conventional “open bolt” fixed firing pin system. The Gevelot D-4 is externally similar to the MAT 49 except for the tubular receiver and non folding magazine chute. The MAT 49 has no separate fire selector and fired full auto only, while the Gevelot features a separate three-position safety selector mechanism on the left side of the trigger housing just above the pistol grip. When the safety lever is rotated forward it locks the bolt either in open or closed position. The Gevarm 9mm submachine guns are well made and claimed to be impervious to sand and mud. Both guns utilized an “anti fouling” device located in the breech face. The Model D-3 with the fixed wooden stock has a unique device located at the rear of the butt stock that may be adjusted for elevation to suit an individual operator. Both weapons utilized 32-round magazines and delivers 600 rpm in full automatic. Despite the numerous unique and interesting features of the Gevarm submachine gun, it was unable to compete with the overall simplicity, reliability and ruggedness of the MAT 49, which was eventually chosen and adopted by the French armed forces in 1949. That weapon saw extensive use in Indo-China, Algeria and, in the 1960s, in Vietnam with great success.
After failing to achieve its goal for a military contract with its development of the D-3 and D-4 9mm submachine guns, Gevelot decided to enter the commercial market in 1960 with the introduction of two interesting .22 semiautomatic rifles. The entry models were designated as the Gevarm E-1 and A-3 models. The E-1 is a take-down type carbine utilizing a 17.5 inch barrel and an 8-shot magazine. The more expensive deluxe Model A-3 rifle features a 21.5 inch barrel and Schnabel type fore end. Both guns have the top of their receiver grooved for a tip-off scope mount. The Gevarm self-loading .22s inherit many of the original features of the 9mm submachine gun version. Both the E-1 and A-3 utilized the fixed firing pin and trigger lock work arrangement of their early 9mm SMG counterpart. In the original design, the 9mm SMG utilized a separate safety/selector mechanism while the .22 caliber self-loaders incorporated a simple push-in locking safety system using the cocking handle to lock the bolt in the open position. This is accomplished by simply pulling the cocking handle until the notch on the bolt passes the sear nose approximately 1/8 inch. The left side of the cocking handle aligns with the corresponding hole in the receiver. Once the pin is aligned to the hole, simply push it in and it will hold the bolt in this position in “safe” mode. To fire the gun, simply pull back the cocking handle towards the right to disengage its connection with the receiver and let the bolt move slightly forward to re-engage the sear on its normal “cocked” open-bolt position. The E-1 model features a reversible recoil spring guide and bolt forward catch. The catch mechanism prevents the bolt from coming off the receiver once the two halves are separated in take-down mode. This model will only take the standard 8-shot magazine while the A-3 takes both the standard and the optional 20-shot magazine. The Gevarm .22 self-loaders were imported into the USA in the 1960s by the Blumfeld Company of Memphis, Tennessee and in Canada by Gevelot Canada and Resvi Ltd., both based in Montreal, Quebec. All three companies have long since gone out of business. In 1969, the E-1 retailed for $73.70 while the more expensive A-3 cost $92.40, as compared to $54.50 for the Ruger 10/22 carbine. The Gevarm .22 rifle’s last year of importation in North America is about 1970.
The experimental Gevarm .22 Automatique Carbine (AC) is identical to the Model A-3 except for the longer 24- inch heavy barrel and the front sight being of a simple blade pattern. Although the receiver of this gun is stamped Automatique Carbine, its long barrel denotes otherwise. The regular A-3 model incorporated a competition type tunnel front sight and comes with five interchangeable inserts. The AC prototype has a built-in buffer housed inside the rear mounted recoil spring guide (not found in either E-1 or A-3 models). The buffer system was incorporated to protect the rear end cap of the receiver from battering during recoil with the gun’s 1,500 + rpm when fired full auto using hot, high velocity ammunition. The bolt design, trigger and safety arrangement on the experimental gun and the commercial models are virtually identical except for the sear and additional fire selector mechanism for the full auto gun. The trigger mechanism of the Gevarm is of extreme simplicity. These components consist of the trigger and the sear, both of which are sturdy steel casting and finely machine finished to specs. These components are heat treated very hard that even a new file will only glide on them like glass. Both the trigger and sear are powered by individual coil springs. The few rugged components and utmost simplicity of the trigger lockwork owes much to the overall reliability of the gun. When the selector is set at semi-auto (selector lever rotated to the rear), the selector pin notch faces the lower front of the sear allowing it to accomplish its normal disconnection process. On fired position (bolt fully closed), the front hook of the trigger and matching rear hook of the sear are not engaged. When the bolt is pulled to the rear and engages the sear bent on “cocked” position, the lower half of the sear will pivot rearward and its hook will automatically rest below the trigger front hook ready to fire the weapon. When the trigger is pulled, the trigger hook will force the sear down and releases the bolt forward to load and fire the gun. As soon as the connection between the bolt and the sear is disengaged, the lower half of the sear will automatically pivot forward and upward by the action of its spring, separating the connection between the trigger and the sear. After firing the shot, the bolt recoils to the rear to eject the empty shell. The sear which has now bounced back to its normal upward position will re-engage the bolt on its forward recoil and will hold it in “open” cocked position. As the bolt engages the sear, the lower half of the sear will swing rearward to its normal stop. To fire the next shot, the trigger pull must be released allowing the trigger front hook to re-engage the sear in the usual manner. In the full auto mode (selector rotated forward), the solid portion of the selector pin blocks the pivoting action of the sear’s lower half during operation thus precluding the disconnection between the trigger and the sear when the trigger is pulled resulting in full auto fire. The sear in thismode merely bounces up and down as the trigger is held down or released during firing. The usual pivoting action of the sear’s lower half is restricted, preventing the usual disconnection between the trigger and the sear.
The system not only proved itself very reliable but outright simple. The original 9mm submachine gun had the fire selector positioned on the left side of the trigger housing above the front stem of the trigger guard. In the .22 caliber version, the fire selector is mounted at the right side of the trigger housing in almost identical location as its 9mm sibling, clearly indicating the similarity in arrangement for trigger lockwork except for the safety function. The selector lever head on the .22 SMG is positioned downward below the stock and vice versa for the 9mm sub guns. The 9mm SMG utilized a stamped trigger housing frame, while the prototype .22 AR had a beautiful machine finish cast alloy material. The one piece wooden stock encloses the housing with the fire selector head visible just forward and above the trigger guard where it can be manipulated conveniently by the trigger finger (for right handed shooters).
The Gevarm .22 AC is a pure performer and its design merits of simplicity is quite advanced for its time. Utilizing a fixed firing pin in the form of a fine vertical ridge on the breech face, assures positive detonation of the primer at all times and twice the ignition power since both the top and bottom of the rim are hit by the firing pin at the same time. No more misfires. The gun has no extractor, yet during testing, the gun never had a single malfunction with over 1,000 rounds fired through it. During the test, the barrel was only cleaned once after 700 rounds were fired to remove lead built-up on the rifling but not to other components. The gun fed and fired every type of ammo used ranging from standard velocity (Remington sub-sonic), hot truncated bullet, Remington Yellow Jacket and ultra-hot CCI Stinger. From solid to hollow point, the gun ate them all without a hitch. Even ammo that had a slightly bent and deformed bullet nose that jammed on other guns, performed flawlessly with the Gevarm.
The secret to the gun’s outstanding feeding reliability relies primarily on the feed ramp. Very few weapons in its class have this unique feature which assures trouble free operation. The rear end of the barrel has a built-in extension approximately 3/ 4-inch that encloses both sides of the magazine lips. Just below the chamber mouth of the extension is a well designed and perfectly machined and polished feed ramp. When a loaded magazine is inserted, the magazine lips seats slightly lower than the “U” shape barrel extension positioning the top round almost directly in line with the chamber mouth. As the bolt moves forward, its sides rides over the barrel extension, striping the top round from the magazine and assisting the cartridge towards the chamber and fires it as the breech comes to a full stop. The superb bolt to barrel extension arrangement virtually eliminated any side play or misalignment of the cartridge towards the chamber as it is being stripped from the magazine. The barrel extension prevented the cartridge from misaligning itself while, and after, it was being stripped from the magazine lips, it simply directs the cartridge to move straight towards the chamber with virtually no hesitation or snag. In addition, the magazine itself is positioned higher than in a normal self loader, preventing the usual tendency of the cartridge nose to glide upward as it hits the feed ramp prior to entering the chamber mouth, which in some cases contributes to jams as caused by lead being shaved off the bullet by a sharp unpolished chamber mouth or ramp.
Another amazing feature of the Gevarm .22 is it’s somewhat smaller than normal ejection port. The overall length of the cartridge is barely the same length of the port. The engineers at Gevarm must have had full confidence to conclude that only the empties come out of the port. Making it any larger will not make it any better. In a sense, they were right as every shell that came out of the ejection port is positively ignited by a very deep vertical firing pin mark. If it failed to detonate, the ammo is definitely dud. In the event this happens, the operator simply cocks the bolt with muzzle pointing upward and the dud cartridge falls easily out of the port. To add more credit to its design simplicity, the Gevarm .22 rifles has no ejector installed to the gun itself. However, the left side lip of the magazine has been formed in such a way that it may function as an ejector. This system worked well. If the operator lost the magazine, the gun can still be loaded singularly since it fires from the open bolt. However, it can not be fired in vertical position or any steep upward angle that may caused the loaded round to fall out of the chamber. This is the only major drawback of the design, something shared by any weapon of this class firing from the open bolt position unless the gun itself has a separate cartridge retainer that will hold the ammo in place while the bolt is held open in single shot operation, in the event that a magazine is lost or becomes unserviceable.
The estimated rate of fire in full auto is between 1,500-1,700 rpm depending on the brand of ammo used. At 25 meters in full auto, the gun delivered an accuracy of a 20-shot group at about inch and a half. Bench rested at 50 meters, it delivers just over 2 inches out of a 20-shot burst. At 75 meters in full auto mode, the group is an impressive 3.25 inches on a bench rest. At 100 meters on a bench rest, the group spread to over five inches, still more potent than a 12 gauge semi-auto shotgun inthis range using 00 buck shot. Shooting off hand, the long barreled AR .22 has no problem placing a full 20-shot magazine to a vital zone of a man size target as long as the operator has a clear vision of his target with the weapon’s iron sight. Ideally, as an all purpose close quarter combat gun, a holo sight would be a perfect combination for this long barreled rimfire burp gun. With a silencer, it’s an effective sentry removal tool for ranges beyond 50 meters. Recoil and muzzle climb is virtually non existence. The gun is truly pleasant to shoot and very accurate. During the test, the fire selector shifted to semi-auto position on numerous occasions while being fired full auto with CCI Stinger. This was eventually traced to a weak selector spring which was immediately replaced and appeared to have corrected the problem.
In summation, the Gevarm .22 Automatique Carbine can be employed as an effective close-quarter defensive arm that is easy to control, maintain and economical to shoot. The only thing that needs Right: . Beautifully machined onepiece aluminum trigger housing with fully assembled trigger lockwork. The massive sear is visible on the top of the housing. A single large hex screw mates the housing to the bottom of the steel receiver shown between the gun’s top and bottom assembly. improvement is the safety system employed. The cocking handle should also have the provision to lock the bolt in a closed position to prevent an accidental discharge in the event that the cocking handle is jarred so that the bolt is pulled to the rear just enough to clear the magazine to pick up a round and fire the gun. The importer of the arm indicated that Gevelot may have the intention of developing and marketing a specialized .22 submachine gun complete with suppressors for SOG in the French military and possibly for the international market back in the 1960s. The experimental gun proved quite successful in this brief testing. There is no doubt that the Gevarm .22 carbine can outperform any other weapons in its class even when subjected to a more elaborate testing due to its simplicity of design and unique chamber feeding system. With the addition of a 200-round drum magazine, a true compact SMG configuration utilizing a simple but rigid folding stock and an effective suppressor, Gevelot would have created the finest rimfire SMG in its class that can easily match or even surpass the formidable AM-180. While these French made “open bolt” rimfire automatics have long been out of production, they represented a special breed of firearms unique by today’s standards. The Gevarm .22s are indeed the simplest and perhaps the most reliable autoloaders in their class.
|This article first appeared in Small Arms Review V11N2 (November 2007)|
and was posted online on November 2, 2012