United Defense M42

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UD M42 submachine gun - .45 ACP

The United Defense UD M42 submachine gun was designed between 1941 and 1942 by American designer Carl Swebilius from the High Standard Manufacturing Company and produced from 1942 to 1943 by the United Defense Supply Corp as a replacement for the Thompson submachine gun, although much of the actual manufacturing was contracted out to Marlin. Versions chambered in 9x19mm and .45 ACP were designed, but the 9mm version was the only version to see significant production. It is fed by a 25 round magazine, although the .45 ACP prototypes use 20 round magazines. Magazines were frequently welded together to facilitate faster reloads, as shown in the image to the right.

The M42 is an extremely simple design with straight blowback operation and built to be made as quickly as possible. This led to design flaws, such as the stamped steel magazines warping and bending and the gun itself prone to jamming in dirty conditions, necessitating frequent cleaning. While the United States Department of War showed interest in procuring large quantities of M42s, only 15,000 were produced due to issues regarding royalties and manufacturing rights. It was mainly used by members of the Office of Strategic Services (OSS) and also extensively airdropped to European resistance forces. The M42 was also issued to Filipino forces, where it saw use into the 1960s.

Specifications

(1942–1943)

• Type: Submachine Gun

• Caliber: 9x19mm Parabellum , .45 ACP (Prototype model)

• Weight: 9 lbs (4.1 kg)

• Length: 32.3 in (82 cm)

• Barrel length: 11 in (27.9 cm)

• Capacity: 20 rounds (.45 ACP prototypes), 25 rounds (9x19mm production version)

• Fire Modes: Semi-Auto/Auto

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The United Defense M42 and variants can be seen in the following films, television series, video games, and anime used by the following actors:

Film

Title	Actor	Character	Note	Date
Pierrot Goes Wild (Pierrot le Fou)		OAS members		1965
Cuba		Cuban guerillas		1979