The M50 Reising was an American-made, select-fire, submachine gun used during World War II.
The M50 Reising used the .45 ACP Cartridge for its ammunition and was fed by either twelve or twenty round clips. This limited the effective range of the weapon to about 100 meters. The muzzle velocity of the Reising was 280 meters per second while its rate of fire was 550 rounds per minute. Reliability in the field was poor, though if used in urban environments, the M50's reliability became more tolerable. However, these kinds of conditions were hardly ever met in combat, particularly in the areas where the US marines would require it to function, the islands of the Pacific.
The total weight of the weapon was about 3.06 kilograms empty while its total length was 85.7 centimeters. The accuracy of the weapon was quite good; the sights being adjustable for up to 274 meters (300 yards). The internal workings of the Reising were housed inside a metal frame which itself was housed inside the wooden exterior.
The first variant of the M50 was the M55 Reising, a model designed for use by the Paratrooper Marines and aptly given a foldable stock. The M55 also had its compensator removed and was fitted with a wooden pistol grip to support the stock.
With the foldable stock, the M55 could have a total length of only 55.6 centimeters and empty weight of 2.81 kilograms. Following the M55 came the M60, a semi-automatic only carbine conversion fitted to fire the .30 Carine round. Developed from this was the M65, a training carbine version fitted for the .22 Long Rifle rimmed Cartridge.
The M50 Reising was created by Eugene Reising in 1940 and produced by the Harrington & Richardson Arms Company in late 1941. The weapon was developed during a time when the United States Military had been scrambling for new weapons to arm its many personnel. Thus, it had been accepted for service with the United States Marine Corps (albeit rejected by the US Army) rather quickly. In the Reising's first combat engagement, the Battle of Guadalcanal, US Marines who operated the Reising noted that the weapon was fundamentally useless as the amount of dirt required to jam it or cause a malfunction was unavoidable. Still serving until the Bougainville Campaign, the Reising was eventually dropped from frontline service in 1943 and simply used stateside until the end of the war and well after, notably by many police forces. In total, some 100,000 examples had been produced all the way until 1945.