The Thompson submachine gun is an American submachine gun, invented by John T. Thompson in 1918, that became infamous during the Prohibition era. It was a common sight in the media of the time, being used by both law enforcement officers and criminals. The Thompson first entered production as the M1921. It was available to civilians, although poor sales resulted from the expense of the weapon: the Thompson gun, with one Type XX 20 shot "stick" magazine, was priced at $200.00 in 1921 (at that time, a Ford automobile sold for $400.00).
Technical Data Weight 10.8 lb (4.9 kg) empty (M1928A1) 10.6 lb (4.8 kg) empty (M1A1) Length 33.5 in (850 mm) (M1928A1) 32 in (810 mm) (M1/M1A1) Barrel length 10.5 in (270 mm) 12 in (300 mm) (with cutts compensator) Cartridge .45 ACP (11.43×23mm) Action Blowback, Blish Lock Rate of fire 600–725 rpm (M1928), 700 rpm (M1A1), 1500 rpm (M1919) Muzzle velocity 935 ft/s (285 m/s) Effective firing range 150m [7] Feed system 20-round stick/box magazine 30-round stick/box magazine 50-round drum magazine 100-round drum magazine