The Probert Encyclopaedia of Warfare

US M3

The US Model M3 was America's solution to the requirement for a cheap and simple sub-machine-gun to replace the heavy and expensive Thompson sub-machine-gun during the Second World War. The M3 was a blowback operated, automatic weapon chambered for the .45 ACP cartridge and the 9 mm Parabellum though the bolt, parallel and magazine needed to be changed to make the switch. The magazine had a capacity of thirty rounds and the M3 had a rate of fire of 400 rounds per minute with a muzzle velocity of 280 meters-per-second. The M3 had a retractable wire stock and a 203 mm long barrel.
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