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M3A1 (Grease Gun) Suppressed

1944 WORLD WAR 2

The history of the suppression of M3A1 (grease gun)

Designed in 1942 and mass-produced in 1943, the original M3/M3A1 "Grease Gun" submachine gun (SMG) line was purchased in 1943 for the very low price of $20 each. The weapon was commissioned from the outset to be cost-conscious mass production to replace the more complex and expensive (though still excellent) M1 Thompson SMG series. About 700,000 of the grease guns were produced throughout their lifespan and remained busy until the 1990s. It was eventually used around the world and in several notable conflicts, justifying the design and some market success. The M3 was eventually slightly improved by the M3A1 initiative and used in the United States.

45 ACP and German 9x19mm Parabellum pistol cartridges are fired by open bolt recoil (although most products are in 0.45 ACP form). The weapon appeared in large numbers from late 1944 to 1945, but did not become more common until after the war.

The name "Grease Gun" comes from the appearance of the gun, which was the grease gun of the mechanic at that time. The original gun was designed by George Hyde of GM's Inland Division and produced by GM's Guide Lights Division in Indiana.

During the war, the Office of Strategic Servicesthe precursor to todays CIAenvisioned a suppressed version of the weapon. This modification retains the basic form and function of the modified M3A1 and adds an integral suppressor barrel to the design.

The barrel is drilled in specific areas to disperse the propellant gases, and is connected to the receiver via a specially designed nut. The design of the silencer is due to OSS requirements, attributed to Bell Labs, while the barrel was manufactured by the Guide Lamp Division and finally assembled by the High Standard Firearms Company.

This weapon is not really a "quiet" weapon, as it still manages the default low speed. 45 ACP cartridge - Subsonic in nature, but still produces noticeable sound. The muffler helped some delay the operator's sound profile, but the combination wasn't very efficient.

The rest of the weapon remains largely the same, including a separate pistol grip, foldable dual-strut wire rest, tubular receiver, and a detachable 30-round straight-box magazine that doubles as a foregrip.

OSS commissioned about 1,000 silenced M3A1s, which certainly limited their overall range in WWII. It turns out that their silencer quality is not as good as that of the British STEN submachine guns - 20% louder than the British design.