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Military


M1 .30 Caliber Rifle, "Garand"

Variants

Though the basic M1 rifle remained largely unmodified throughout its career, many modifications of the weapon were tested. The weapon also served as a starting point for development of a lightweight rifle to replace it, which led to the development of the M14 rifle. In total, 14 subvariants of the M1 rifle were assigned designations, while a number of experimental rifles used the M1 rifle or components thereof as a starting place.

The M1E1 tested a modified cam angle in op-rod, while the M1E3 featured a roller added to bolt's cam lug. The M1E4 had a gas cutoff and expansion system w/ piston integral to op-rod. The M1E9 was similar to M1E4, but with the piston separate from op-rod. The M1E10, M1E11, M1E12, and M1E13 all featured modified gas systems. The M1E10 used a direct gas system similar to that use on the the Swedish Ljungman rifle, a type of operation which was also subsequently used on the M16 rifle. The M1E11 used a short-stroke Tappet gas system. The M1E12 used a gas impingement system different from the Ljungman rifle. The M1E13 used a White gas cutoff and expansion system.

The M1E2, M1E6, M1E7, and M1E8 were all sniper versions of the M1 rifle. The M1E2 had a prismatic telescope and mount, while the M1E6 had a mount for a traditional telescope. The M1E7 and M1E8 models differed only in the telescope mounts. The 2 variants were standardized as the M1C and M1D respectively. The M1C mounted a model M81 2.5x telescope on a Griffin and Howe mount, while the the M1D featured an M82 2.5x telescope on a Springfield Armory mount. While both models were standard with either the M81 or M82, they could be used interchangably, and the M84 telescope subsequently replaced both types. Both rifles were used as sniper rifles during World War II, Korea, and during the early years of the conflict in Vietnam. Although considered obsolete, the M1D remained the official US Army sniper rifle until the mid-1960s, when it was replaced by the M21. Both versions used the standard Army .30-06 cartridge loaded manually, or in 8-round clips. The USMC used a sniper rifle similar to the M1C, with a Stith-Kollmorgen 4x scope on an improved Griffin & Howe mount. The mount was designated as the MC-1 and rifles fitted with it were known either by that nomenclature or as the M1952/MC1952.

Short barreled versions of the M1 rifle were also developed. An experimental Garand rifle with an 18 inch barrel was designated as the T26, while a variant of the M1 rifle utilizing the 18 inch barrel and a side-folding stock was designated as the M1E5. Neither rifle was formally adopted, though commercial copies of what became known as the "Tanker Garand" were produced.

The Army Ground Forces stated in September 1944 that a requirement existed for a weapon that would be comparable in size, weight, and efficiency to the M1 rifle and capable of both automatic and semiautomalic fire. To meet this requirement, the Ordnance Department initiated, in October 1944, a project to modify the M1 rifle. The new rifle was to be equipped with a detachable bipod and, when fired from the bipod, was to be as effective as the standard M1918 BAR. The proposed weapon was also to include a 20 round magazine.

Springfield Armory had alread begun work along similar lines in early 1944. The development resulted in an M1 rifle derivative, the T20 rifle, incorporating full and semiautomatic fire. Full automatic fire was accomplished by an independent sear release. The T20 was capable of automatic fire from an open bolt and semiautomatic fire from a closed bolt position. The open bolt feature did not adequately solve cook-off problems. The basic principle of operation was considered satisfactory. Development of the T20 model terminated in January 1945 with recommendations that minor design changes and strengthening of various components be made, including using a type of magazine unique to the weapon. A rifle incorporating these minor design changes was designated T20E1.

In early 1945, the T20E2 rifle was developed. This rifle had both fully automatic and semi-automatic fire capability. Fully automatic fire was achieved by a connector assembly, which was actuated by the operating rod handle. This, in turn, actuated a sear release or trip which, with the trigger held to the rear, disengaged the sear from the hammer lugs immediately after the bolt was locked. This model included a recoil check on the muzzle. The bolt was modified to ease feeding and extractior. The receiver was slightly longer than that of the M1 rifle. This allowed the bolt to travel further to the rear and improve feeding. The T20E2 also had a gas port located approximately 1.5 inches from the muzzle. The T20E2 rifle was designated Limited Procurement Type in May 1945. A heavy barrel variant, designed as a potential replacement for the M1918A2 Browning Automatic Rifle was also developed, referred to as the T20E2HB. The project was terminated in March 1948.

A parrellel effort began in early 1944 by the Remington Arms Company, resulting in the T22 rifle. Similar to the T20 series, the T22's fire control was designed entirely by Remington. In this design effort, fully automatic fire was accomplished in the open bolt position and semiautomatic fire from a closed bolt position. The open bolt feature did not effectively prevent cook-off. A design incorporating various design changes was designated as the T22E1.

The T22E2 rifle was developed from the earlier T22 rifles by Remington Arms Company. On the T22E2, fully automatic fire was accomplished in the open bolt position, but semi-automatic fire was accomplished from a closed bolt position. The T22E2 incorporated a slight change in the trigger group to simplify manufacture, as well as an improved magazine catch. The major advantage of the T22E2 was in its adaptability to remanufacture of Ml rifles as a peacetime operation. The T22 project to modify the M1 rifle was terminated in March 1948.

Remington also developed a fire-control test bed with a high stock, using the fire-control setup of the T22 series. The rifle, designated as the T23, was a modification of the Ml rifle to provide fully and semi-automatic fire. Automatic fire was to be provided by an independent hammer release. The T23 was advantageous from the standpoint of design, durability, and minimization of functional stresses. The mechanism timing required that the rifle be fired fully automatic from an open bolt approximately 20 percent of the time. Tests of the weapon indicated the desirability of firing from the closed bolt position. The tests also indicated that a new magazine should be designed rather than attempt to modify the BAR magazine. A device designed to increase gun stability during automatic fire was definitely needed.

The T24 rifle, another Remington fire-control test bed, was also a modification of the Ml rifle to provide fully and semi-automatic fire. Automatic fire was provided by an independent sear release. The project was initiated simultaneously with the T23 rifle development in October 1944. The T24 fired fully automatic from a closed bolt position at all times. The T23 and T24 projects were terminated in March 1948.

The termination of project to modify the M1 rifle, which had resulted in the T20, T22, T23, and T24 rifle types, was in part due to a light weight rifle development program that had been initiated at Office, Chief of Army Ordnance in March 1945. The new development led to a new cartridge, the T65, which eventually became the NATO standard 7.62mm cartridge. Not all the rifles tested were derivatives of Garand's M1, but the T44 series, which became the M14 rifle was. In all, there were 7 experimental rifles (along with a derivative of the M1 rifle itself) based on the M1 or components of the Garand design in the lead up to the T44. The original T44 was based on the T37 rifle and utilized a gas operation system derived in part from the T25 rifle, the breech and magazine catch of the T20E2, and the magazine of the T31. The T44E2 outright used the M1 rifle's gas system. The final T44E4 and T44E5, which were subsequently standardized as the M14 and M15 rifles, owed much to the M1 rifle.

The T27 rifle project, initiated in April 1946, which modified the M1 rifle to fire the new improved T65 .30 caliber ammunition. The rifle was capable of selective fully and semi-automatic fire. A variant of the T22 using the T27's fire control configuration was designated as the T22E3. A heavy barrel version, like the T20E2HB, was also developed as the T22E3HB. This project was terminated in March 1948. Another similar project had started in June 1944. The T35 rifle, however, was semi-automatic only. It incorporated a drop wood stock, iron aperture rear sight, and post front sight. The T35 also featured a side-loading internal magazine instead of the M1 rifle's standard magazine. This particular development was suspended in the latter part of 1950. The M1E14 took lessons learned from the T35 and also featured a press-in chamber insert to prevent a need to change the weapon's barrel.

The T31 rifle development program was begun in March 1947. This weapon, designed by John Garand was a lightweight, selective fully and semi-automatic rifle with an in-line stock. It was also intended to replace the Ml rifle, M2 carbine, M3A1 submachine gun, and the M1918A2 Browning Automatic Rifle. The T31 was a novel approach to infantry rifle design and had unusually low stripping forces and energies. It also incorporated a so-called "bullpup" design, in which the weapon's action was placed behind the pistol grip, inside the stock of the weapon. The magazine design was later incorporated into the T44 rifle. Attempts were made to reduce recoil and eliminate flash and muzzle blast. These attempts were unsuccessful and the development program was suspended in late 1950.

The development program for the T33 was initiated in March 1949. The rifle was developed on the initiative of a private inventor and owner of the Clarke Arms Company, with guidance from the Office, Chief of Ordnance. The resulting weapon was based on the M1 rifle and chambered for the T65 cartridge. The project was suspended in late 1950 because the weapon lacked sufficient ruggedness and durability.

The T36 was a lightweight rifle modified from the T20E2 rifle, being officially designated in November 1949. The weapon was designed to fire the 7.62mm NATO ammunition. The T36 rifle featured both fully and semi-automatic fire capability, firing from a closed bolt position. It had a drop wood stock, iron aperture rear sight, and post front sight. A modified T25 rifle magazine design was incorporated into the rifle. The magazine functioned very well. Further modification included a one-piece hand guard and a special butt plate. The T36 rifle development was terminated in the latter part of 1950.

The T37 rifle was a lightweight rifle modified from the T20E2 and incorporated features from the T36 rifle. The rifle fired NATO ammunition and had both fully and semi-automatic fire capability. The important modifications included a lightweight 22-inch barrel with the gas port approximately 4 inches from the muzzle and a lightweight wooden stock. The design included the T20E2 receiver, but with filler blocks fore and aft of the magazine. Further revisions incorporated a lightweight stabilizer/flash suppressor and a bolt buffer. Following tests, recommendations were made for further development of a lightweight rifle that would be manufactured with existing production tools.

While the T37 led directly to the T44, another rifle was also put into development in October 1951. The T47 was a successor to the T25 and featured a lightweight barrel and fully and semi-automatic fire capability. The weapon fired from the closed bolt position. The bolt of the T47 rifle was locked and unlocked by the tilting action of the breech lock. This was the chief feature that distinguished it from the T44 rifle. The T44 was considered superior and T47 development program was terminated.

Though the US Army's developments led to the adoption of a new rifle, the M14, the conversions of the M1 rifle to the new 7.62mm ammunition were adopted by the US Navy. The M1E14 design was adopted by the US Navy as the Mk 2 Mod 0 rifle. The T35 design was adopted as the Mk 2 Mod 2. Another development along these lines was designated as the Mk 2 Mod 1. Springfield Armory also tested a modified M1 rifle in the .280 caliber cartridge in 1950. The British had developed the cartridge before the adoption of the 7.62mm NATO cartridge.

Conversions of the M1 rifle to the new NATO standard ammunition and modifications similar to the various experimental rifles and the M14 were developed around the world, mostly in Europe by NATO allies. The most notable of these was the Beretta BM-59 rifle. Beretta converted a number of M1 rifles to the new ammunition for the Danish military, with these being designated as Gv M/50.




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Page last modified: 07-07-2011 02:45:45 ZULU