Thompson SMG
American .45 ACP submachine gun, icon of the Prohibition and World War II: blowback action, drum or box magazine and wooden stock.
Thompson SMG
Community
Data trust
- Reliability
- Unverified
- Sources
- Sources pending review
Identity
- Designation
- Thompson SMG
- Alias
- Tommy Gun / M1928 / M1A1
- Manufacturer
- Auto-Ordnance Company
- Country
- United States
- Year
- 1921
- Category
- Submachine gun
- Status
- Historic
Ballistics
- Caliber
- .45 ACP
- Muzzle velocity
- 285 m/s
- Rate of fire
- ~700 rpm
- Effective range
- 150 m
- Maximum range
- 250 m
Dimensions
- Barrel length
- 267 mm
- Overall length
- 813 mm
- Empty weight
- 4.9 kg
Mechanics
- Operating system
- Blowback
- Bolt / action
- Unlocked bolt
Feed
- System
- Box or drum magazine
- Standard capacity
- 30 rounds
Fire modes
Historical profile
Development
The project was started in 1916 by General John T. Thompson, who sought a weapon capable of "sweeping" the trenches of World War I: a portable machine gun, which he named "submachine gun." The chosen cartridge was the .45 ACP, already issued with the Colt M1911.
The first "Persuader" prototype of 1917 used the Blish delayed-blowback system; the M1921 commercial model went into production at Colt in 1921, too late for the war but in time for Prohibition.
Design
The military M1928A1 model kept the Blish system and accepted 20/30-round box magazines or 50/100-round drums. It weighed about 4.9 kg empty: heavy for its class, but with very controllable recoil thanks to its moderate cyclic rate.
The wartime M1 (1942) and M1A1 (1943) variants dropped the Blish system in favor of straight blowback, eliminated the drum magazine, simplified the sights and drastically reduced production cost.
Operational service
In the 1920s–30s the Thompson became a symbol of Prohibition: used by gangsters like Al Capone (Saint Valentine's Day Massacre, 1929) and, in response, by J. Edgar Hoover's FBI.
During World War II it was produced in over 1.5 million units (M1928A1 + M1/M1A1) for the US Army, US Marines, the British Special Operations Executive and the Red Army via Lend-Lease. It remained in limited service in Vietnam and in colonial wars through the 1970s.
Variants
Main users
United States · United Kingdom · USSR · France
Key components
- ●Stock — Shoulder rest.
- ●Receiver — Weapon body with internal mechanisms.
- ●Grip — Primary grip.
- ●Magazine — Cartridge feed.
- ●Barrel — Guides the projectile.






