Thompson submachine gun

The Thompson submachine gun (nicknamed the Thompson) 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 was also known informally as: the "Tommy Gun", "Trench Broom", "Trench Sweeper", "Chicago Typewriter", "Chicago Piano", "Chicago Style", "Chicago Organ Grinder", and "The Chopper".

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

Thompson submachine gun
Class Manportable
Type Machine Guns
Manufacturer Auto-Ordnance Company
Origin United States of America
Country Name Origin Year
United States of America 1919
Country Name Operational Year Retirement Year
Bosnia-Herzegovina 1992 1995 View
China 1927 1936 View
Greece 1946 1949 View
Ireland 1922 1923 View
Ireland 1968 1998 View
Korea 1950 1953 View
United States of America 1898 1934 View
Vietnam 1946 1954 View
Vietnam 1955 1975 View
ManufacturerName Production From Production To Quantity
Auto-Ordnance Company 1921 View
Birmingham Small Arms Company 1921 View
Colt's Manufacturing Company 1921 View
The Thompson Submachine Gun was developed by General John T. Thompson who originally envisioned an auto rifle (semi-automatic rifle) to replace the bolt action service rifles then in use. While searching for a way to allow such a weapon to operate safely without the complexity of a recoil or gas operated mechanism, Thompson came across a patent issued to John Bell Blish in 1915 based on adhesion of inclined metal surfaces under pressure. Thompson found a financial backer, Thomas F. Ryan, and started the Auto-Ordnance Company in 1916 for the purpose of developing his auto rifle. It was primarily developed in Cleveland, Ohio. The principal designers were Theodore H. Eickhoff, Oscar V. Payne, and George E. Goll. By late 1917, the limits of the Blish Principle were discovered: rather than working as a locked breech, it functioned as a friction-delayed blowback action. It was found that the only cartridge currently in U.S. service suitable for use with the lock was the .45 ACP round. Thompson then envisioned a "one-man, hand-held machine gun" in .45 ACP as a "trench broom" for use in the ongoing trench warfare of World War I. Payne designed the gun itself and its stick and drum magazines. The project was then titled "Annihilator I" and by 1918, most of the design issues had been resolved. However, the war ended two days before prototypes could be shipped to Europe.

At an Auto-Ordnance board meeting in 1919 to discuss the marketing of the "Annihilator," with the war now over, the weapon was officially renamed the "Thompson Submachine Gun." While other weapons had been developed shortly prior with similar objectives in mind, the Thompson was the first weapon to be labeled and marketed as a "submachine gun." Thompson intended the weapon as an automatic "trench-broom" to sweep enemy troops from the trenches, filling a role for which the Browning Automatic Rifle (BAR) had been proven ill-suited. This concept had already been developed by German troops using their own Bergmann MP18, the world's first submachine gun, in concert with sturmtruppen tactics.

Type Submachine gun
Place of origin United States
Service history
In service 1938–1971 (officially, U.S. military)
Used by Australia, Belgium, Brazil, British Raj British India, Canada, Colombia, Dominican Republic, People's Republic of China, Republic of China, Croatia, France, Egypt, Greece, Haiti, Indonesia, Ireland, Israel, Italy, Japan, Republic of Korea, Luxembourg, Malaysia, The Netherlands, New Zealand, North Vietnam, Philippines, , Poland, Portugal, South Vietnam, Soviet Union, Sweden, Turkey, United Kingdom, United States, West Germany, Yugoslavia
Wars Banana Wars

Irish Civil War

World War II

Chinese Civil War

First Indochina War

Greek Civil War

Korean War

Vietnam War

The Troubles

Bosnian War

and numerous others
Production history
Designer John T. Thompson
Designed 1917–1920
Manufacturer Auto-Ordnance Company (originally)

The Birmingham Small Arms Company Limited


Savage Arms

RPB Industries
Produced 1921–Present
Number built Approx. 2,000,000
Variants See Variants section
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 160 feet (50 m)
Feed system 20-round stick/box magazine

30-round stick/box magazine

50-round drum magazine

100-round drum magazine

(M1 and M1A1 models do not accept drum magazines)

End notes