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Object Record

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Catalog Number 2014.018.002
Description 1921 Thompson Submachine Gun (Tommy Gun) with a 25-round stick magazine. Firearm is comprised of black-painted steel with wooden front and back hand grips and shoulder butt. Butt end of rifle has a black-painted metal plate. There is a metal loop on the bottom end of rifle butt, probably for a shoulder strap. Barrel above front hand grip has 29 circular ridges. Top of barrel end, just in front of sight, has 4 rectangular openings. Proper left side near trigger has two levers: one is for "FULL AUTO" or "SINGLE," and the other is for "FIRE" or "SAFE." This type of firearm was used by the military during WWII and would be part of a sheriff's arsenal.
Object Name Gun, Machine
Collection 3D - Armaments
Title SMCSO Thompson Submachine Gun (Tommy Gun), 1921
Date 1921
Creator MGC Modelgun Corporation
Role Manufacturer
Inscription Text "MODEL OF 1921 / NO." (engraved on proper left, above back hand grip); "THOMPSON SUBMACHINE GUN. / MANUFACTURED BY / MGC MODELGUN CORPORATION / TOKYO, JAPAN" (embossed on proper left, above front of rifle butt)
Provenance This artifact was owned and used by the San Mateo County Sheriff's Office.
Notes [] "The Thompson submachine gun (nicknamed the Thompson or Tommy 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.[6] The Thompson was also known informally as: the "Tommy Gun", "Trench Broom", "Trench Sweeper", "Chicago Typewriter", "Chicago Piano", "Chicago Style", "Chicago Organ Grinder", and "The Chopper".[7][8][9][10][11]

The Thompson was favored by soldiers, criminals, police and civilians alike for its ergonomics, compactness, large .45 ACP cartridge, reliability, and high volume of automatic fire. It has since gained popularity among civilian collectors for its historical significance.

...In 1938, the Thompson submachine gun was adopted by the U.S. military, serving during World War II and beyond."
Dimensions H-10 W-34.5 D-1.75 inches
Dimension Details with magazine
Search Terms 1920s
Military Weapon
San Mateo County
San Mateo County Sheriff's Office
San Mateo County-Sheriffs
World War II
World War Two
Subjects Arms & armament
World War II