A cheap replacement for Thompson: the M3 submachine gun
In the army, a new model of automatic weapons received the playful nickname "Grise Gun", or simply "Greaser" - "Grease gun", primarily because of its appearance and shape. Outwardly, the new submachine gun really resembled this tool, which was widely used in mechanical engineering for lubricating various moving parts. Like the more famous Thompson, the M3 submachine gun used .45 APC (11,43x23 mm) pistol cartridges. Moreover, the new weapon was easier to manufacture and operate, and also easier with some loss of accuracy. Especially the new submachine gun was in demand by the crews tanks and other armored vehicles, its small size was very welcome.
The development of a new submachine gun for the American army was carried out by the team of designers of the General Motors Corporation (gunsmith George Hyde of the Firearms Research Corporation was responsible for creating the submachine gun, engineer Frederick Simson of the Inland Manufacturing Division production of new items). The weapon was originally created to replace the Thomspon submachine gun as a cheaper and more technologically advanced in production. Work began in October 1942 of the year, while in April of the same year, another test of George Hyde, the M2 submachine gun, which was recommended for use but was released in a very small batch of 400, ended. This model was difficult to manufacture, in particular, it required complex metalworking operations, so it could not compete with the new submachine gun МNNXX.
Having a simpler and more technological design, the new M3 submachine gun set a new value bar. It was significantly cheaper than the Thompson. Each Thompson submachine gun in February 1944 of the year (the cost of the model M1А1 at that moment was the lowest for all history production) cost 45 dollars, at the same time a “lubricating syringe” or “oiler”, as the M3 submachine gun was called by the US military, cost the US budget 15 dollars apiece already in 1943 year. At the same time, the novelty was lighter and smaller, the M3 without cartridges weighed 3,7 kg, while the mass of the empty Thompson М1А1 was 4,5 kg.
12 December The 1942 of the M3 submachine gun was officially adopted by the American Army under the designation “United States Submachine Gun, Cal. .45, M3 ». The upgraded version, designated M3A1, has been produced in the USA since December 1944. Until the end of World War II, 15 369 submachine guns of this model were assembled, another 33 200 М3А1 was released already in the years of the Korean War. Received the nickname “lubricant syringe” in the army for its unusual appearance, the new submachine gun justified its nickname by the fact that it required constant lubrication to ensure the reliability of its units and mechanisms. Especially for this purpose, the designers even placed a small size integrated lubricator in the handle М3А1, it was closed with a screw cap in the lower part of the handle of the weapon.
About a thousand submachine guns were produced in the caliber 9-mm chambered for 9x19 mm Parabellum. This version received the designation "US 9 mm SMG". This submachine gun could also be equipped with a silencer from Bell Laboratories. In 1944, in this version, weapons were supplied to the fighters of the Office of Strategic Services. Also in a limited series, special kits were produced for changing the caliber of the submachine gun from the .45 ACP cartridge to the 9mm Parabellum. The sets included a barrel, a bolt, a magazine receiver adapter and a return spring. In this case, the shops from the British-made STEN submachine guns were used with the M3. During the Second World War, the M3 submachine guns were actively used by the American infantry, reconnaissance units, and also tank units.
The automatic machine gun M3, designed to replace at the front of the machine guns Thompson, worked on the use of recoil with the free gate. Drummer was located motionless in the mirror shutter. Shooting from the M3 was carried out with an open shutter. The body of the weapon was stamped and made of sheet steel. The M3 submachine gun did not have either plastic or wooden parts in its design. The barrel of the weapon almost the entire length was outside the bolt box, the protective cover was not provided. A threaded bushing was pressed onto the breech breech, which was screwed into the gate box when the weapon was assembled. The location of the barrel in line with the butt allowed the shooter to more easily control the impact when shooting. In later versions of the M3A1 submachine gun, a conical flame arrester was mounted on the barrel.
The trigger was located at the bottom of the bolt box, while the submachine gun had only one firing mode - automatic. At the same time, the relatively low rate of fire (up to 450 shots per minute) allowed even inexperienced shooters to fire with single shots. The trigger mechanism included a trigger with a spring, the trigger pull and the trigger lever (sear). The loading mechanism was located in a separate box, it was attached to the bottom of the bolt box with a special trigger guard. The loading mechanism of the M3 submachine gun consisted of a loading handle with a spring, a lever and a pusher.
The distinctive features of the model attributed the cocking handle. It was cocked backwards, like the handle of a Maxim machine gun. When the shooter retracts the loading handle, the lever turns, and the pusher connected to the lever retracts the bolt of the submachine gun. Such a cocking pattern proved to be not reliable enough in the future. As a result, in the М3А1 model, it was decided to abandon it, replacing the cocking knob with a hole in the bolt. As a result of the changes for the cocking, the soldier had to hook the hole with his finger and move the bolt back. In addition, on the submachine gun М3А1 increased the size of the window, designed for ejection sleeves. The spring-loaded cover of the window for ejection of the sleeves also served as a fuse, blocking the bolt in the front or rear position when it was closed. A reflector was welded to the front of the loading mechanism box.
The sights of the weapon were simple and included an unregulated front sight and a diopter sight designed for a fixed shooting distance - 100 yards. A retractable shoulder support made of steel wire was used as the butt. In this case, the shoulder support could perform several functions at once. His right rod, being separated from the weapon, could be used as a ramrod, and in the back of the shoulder rest of the M3A1 submachine gun was a clip to facilitate the loading of ammunition magazine.
The experience of the combat use of the MZ submachine gun demonstrated to the military that the weapon was not as perfect as it was thought during the tests, various changes had to be made to its design. In addition, the developers believed that they could further simplify the design, which will speed up the production process and further reduce the cost of production of the model. So, already in December 1944, an updated modification of the submachine gun was introduced, which received the designation MZA1. It differed from the original in the absence of a cocking mechanism using a special lever. As noted above, to prepare the weapon for firing, it was necessary to insert a finger into the hole in the bolt and pull the bolt back. For this, designers needed to increase the size of the hole for ejection of a spent cartridge case, and also to use a lid on a hinge, in which a metal pin remained to lock the bolt in the front and rear positions.
An oiler was inserted into the pistol grip; in addition, other minor changes appeared in the weapon design. Parts of the weapon were given such a form that allowed them to be used as tools for assembling and disassembling individual components and mechanisms М3А1. The updated submachine gun, like its predecessor, was completed with a box magazine on 30 of cartridges with a staggered arrangement of cartridges and a single-row output. The store was the subject of complaints of soldiers throughout the entire service of the weapon, it was difficult to equip it, it was also often jammed, but the designers considered the solution to the problem costly and left everything as is.
It was originally planned that the new M3 submachine gun could be produced in such quantities that it would replace Thompson submachine guns in the army. But due to unforeseen delays in production, as well as time spent on eliminating the deficiencies identified during actual operation of the weapon, the M3 did not become a full-fledged replacement of Thompson in the US Army during World War II, and the purchase of Thompson’s submachine guns continued until February 1944 of the year. At the same time, the M3 (as, indeed, the British Sten) never enjoyed the love of ordinary infantrymen, who gave the submachine gun a scornful and humorous nickname. Much more popular with American soldiers was the M1 carbine, which was less effective in melee, but more like a real weapon.
Total from 1940 to 1944. American industry has released the 1 387 134 Thompson and 622 163 submachine gun M3 / M3A1. One released submachine gun M3 accounted for approximately 2,2 "Thompson." At the same time, a considerable part of the Thompsons in the framework of the Lend-Lease program turned out to be in the USSR - around 135 thousand guns, which were supplied mainly as additional equipment for various military equipment.
After the end of World War II, thousands of American-made M3 submachine guns were scattered around the world, and weapons were actively exported. Due to the simplicity of the design, the M3 and M3-1 models could be maintained in working order even by a person with a minimum set of craft skills. And some states, for example, Argentina and China, even produced a “grease gun” serially. Weapons were also massively used during the Chinese civil war by supporters of the Republic of China, and since 1950 they began to produce weapons on the island of Taiwan. American soldiers fought with M3 submachine guns in Korea and Vietnam. In the infantry, it remained in service until the 1960-ies, and in the tank units of the United States, these weapons were in service until the beginning of the 1980-ies.
Tactical and technical characteristics of the machine gun M3:
Caliber: 11,43 mm.
Cartridge: .45 ACP (mm 11,43x23).
Weight without cartridges: 3,63 kg (М3А1 - 3,47 kg).
Length: 570 / 745 mm (with folded / unfolded butt).
Barrel length: 203 mm.
Rate of Fire: 450 shots / min.
Initial bullet speed: 280 m / s.
Effective range: 100 yards (91 m).
Shop: boxed on 30 cartridges.
Information sources:
https://www.armoury-online.ru/articles/smg/us/m3-m3a1
http://weaponland.ru/publ/11_43_mm_pistolet_pulemet_obr_1943_g_m_3/7-1-0-1458
https://smallarms.ru/article?arms=m3
http://zonwar.ru/pp/m3a1.html
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