Thompson M1A1
Auto-Ordnance Corporation · Submachine Gun · Discontinued · 1942
Also known as: Tommy Gun, Thompson Gun, Chicago Typewriter, Trench Broom, The Annihilator
Overview
The Thompson M1A1 is a select-fire submachine gun chambered in .45 ACP, produced by Auto-Ordnance Corporation since 1942. Featuring a 30-round magazine capacity, this submachine gun offers generous firepower for duty use and home defense.
Specifications
| Weight (empty) | 4800 g (169.3 oz) |
| Weight (loaded) | 5100 g (179.9 oz) |
| Overall Length | 813 mm (32.01") |
| Barrel Length | 267 mm (10.51") |
| Height | 140 mm (5.51") |
| Width | 34 mm (1.34") |
| Action Type | Blowback |
| Firing Mechanism | Fixed Firing Pin |
| Trigger Type | Select Fire |
| Magazine Capacity | 30 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 280 m/s (919 fps) |
| Muzzle Energy | 585 J (431 ft·lbf) |
| Effective Range | 150 m (164 yd) |
| Maximum Range | 1500 m (1640 yd) |
| Rate of Fire | 700 rpm |
| Barrel Rifling | Right Hand |
| Rifling Twist | 406 mm (15.98") |
| Number of Grooves | 6 |
| Frame Material | Steel |
| Barrel Material | Steel |
| Stock Material | Wood |
| Finish | Parkerized |
Calibers
- .45 ACP · primary — also known as .45 Auto, .45 Automatic Colt Pistol, 11.43x23mm
Features
- Firing modes: Semi Automatic, Full Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Fire Selector, Grip Safety
- Features: Select Fire, Side Charging Handle, Fixed Firing Pin, Simplified Construction, Flip Up Rear Sight, Compensator
Variants
- Thompson M1928A1 — Earlier Model
- Thompson M1 — Simplified
- Thompson M1921 — Commercial
- Thompson M1923 — Military Trial
Base model
Service history
Operators
- United States Army · adopted 1942 · as M1A1
- United States Marine Corps · adopted 1942 · as M1A1
- United States Army Rangers · adopted 1942 · as M1A1
- British Armed Forces · adopted 1940 · as Thompson
- Canadian Armed Forces · adopted 1940 · as Thompson
- Australian Defence Force · adopted 1941 · as Thompson
- Soviet Red Army · adopted 1941 · as Thompson
- French Army · adopted 1944 · as Thompson
- French Foreign Legion · adopted 1944 · as Thompson
- Philippine Army · adopted 1942 · as Thompson
- Yugoslav People's Army · adopted 1950 · as Thompson
- South Vietnamese Army · adopted 1955 · as Thompson
- New Zealand Armed Forces · adopted 1941 · as Thompson
- Swedish Armed Forces · as Thompson
Conflicts
- World War II (1939-1945)
- Korean War (1950-1953)
- First Indochina War (1946-1954)
- Chinese Civil War (1927-1949)
Production
Estimated total produced: 1,500,000 · Production years: 1942-1944
Over 1.5 million Thompson submachine guns of all variants produced during WWII by Savage Arms and Auto-Ordnance; M1A1 was the most produced variant
Origin
Country of origin: United States
Designer: John T. Thompson
Discontinued: 1971
Notes
The M1A1 variant featured significant simplifications from the M1928A1: removal of the Blish lock (replaced with simple blowback), elimination of the finned barrel, removal of the Cutts compensator on some models, simplified rear sight (fixed aperture replacing adjustable ladder sight), and removal of drum magazine capability. Manufactured primarily by Savage Arms Corporation and Auto-Ordnance Corporation, over 1.5 million Thompson submachine guns were produced during WWII. The weapon was officially replaced by the M3 'Grease Gun' in 1943, but remained in widespread use due to soldier preference and existing inventory. North Vietnamese forces produced crude copies in jungle workshops during the Vietnam War. The Thompson's cultural impact extended far beyond military service, becoming one of the most recognizable firearms in history through its association with both WWII combat and 1920s-30s gangster era.
Background
The Thompson earned the nickname 'Chicago Typewriter' from its association with 1920s-30s gangsters like Al Capone, but became a symbol of Allied victory in WWII. The M1A1 was a radically simplified version that eliminated the complex Blish lock -- which turned out to have never actually worked as intended. The original M1921 cost $200 in 1921 (equivalent to over $3,000 today), making it one of the most expensive submachine guns ever produced.