Thompson Submachine Gun


Method of Operation–Selective Fire
Caliber–.45 ACP
Weight–11 pounds
Maximum Effective Range–50 yards
Cyclic Rate–725 rpm

(left) Sgt James Moll, A 1/7, poses with his M1928A1 Thompson on Pavuvu following the Peleliu campaign, Fall 1944. Photo courtesy 1stSgt Charles Owens


The Thompson Submachine Gun was one of the 20th Century's most legendary weapons. Marines used the "Tommy Gun" is various roles from the 1920s through the Korean War era. Its dependability and stopping power provided Marines an edge in the tough battles of the Pacific campaigns.

(above) Pvt Roy Grier, 1st Marine Raider Regiment, looks at a captured Japanese pistol following the Bairoko raid–July 1943. His weapon is the M1928A1 Thompson USMC

Firearms designer and retired Soldier John T. Thompson began development of his automatic weapon during World War I. He called it the "trench broom" and designed it to use the .45 ACP cartridge. Thompson later changed the name of his weapon, coining the term, "submachine gun," for it.

Mr. Thompson established the Auto-Ordnance Corporation in 1919 to assemble and market his gun. Marines first tested it at MCB Quantico in the Spring of 1920. The results were favorable, but the Thompson Submachine Gun was not adopted, mostly because the armed services couldn't afford to officially adopt any new weapons.

Even though the Thompson was not type-classified, the Marine Corps still bought about 700 of the guns in the mid-1920s. These weapons were used in combat in Nicaragua, guarding the mail in the US and in China. The Thompson quickly became a popular weapon with Marines.

The Thompson Submachine Gun was produced to a high standard of quality. It was a complex weapon that used the patented Blish Lock. The guns were made with a deeply blued finish and beautiful wood stocks. They could accept both stick and drum magazines and came with a variety of accessories.


Auto-Ordnance produced two models of the Thompson prior to World War II- the M1921 and the M1928. The latter gun was modified in the early 1930s and became the M1928A1. Both guns were identical in their method of operation, using the delayed blowback principle.

At the start of World War II, the Thompson was the only submachine gun in the US inventory. Demand skyrocketed and simplified methods of production had to be developed. In early 1942, the Thompson was completely redesigned. The new weapon was type-classified in April 1942 as the Submachine Gun, M1.

Gone was the pre-war blued finish, replaced by the GI-issue parkerization. The newly redesigned Thompson would only accept stick magazines. The Blish Lock was retired after Auto-Ordnance found out it was unnecessary to the Thompson's operation. The M1 was still manufactured to a high standard of quality. It was further simplified as the Submachine, M1A1.

(left) A smiling Marine poses with his M1928A1 Thompson on Okinawa, 1945. His weapon has a 20 round stick magazine.

USMC Photo

As the war progressed, HQMC decided to replace all submachine guns with M1 carbines. This goal was never achieved, although the number of submachine guns in front line service decreased with each new Table of Organization.

Thompsons were widely issued to the Raiders and Paramarines. For example, in the 2nd Raider Battalion, each fire team was equipped with a Tommy Gun. In line divisions, Thompsons were issued to various Marines, dependent on the Table of Organization. At various times in the war, rifle platoon sergeants and guides and mortar squad leaders were issued with these weapons.

Marines either loved or hated the Thompson. Some valued its high volume of fire at close ranges. Other felt the gun was worthless because of its short effective range. Many Marines swore by the stopping power of the .45 ACP cartridge. Others felt the gun was much too heavy.

The Thompson was a intelligently designed, reliable gun that served Marines well for many years. It was also an example of the best in American firearms design and production. It earned its place among the weapons of the World War II Gyrene.

(left) A Marine war dog handler and his K-9 partner in the South Pacific–1943. The Marine is armed with an M1928A1.

USMC Photo

(left) A Marine of the 1st MarDiv fires his Thompson at a Japanese bunker on Cape Gloucester, January 1944.

USMC Photo

(left) Marines of 2/1 fighting on Wana Ridge, Okinawa–18 May 1945. At left, Davis Hargraves provides covering fire with his M1 Thompson while BAR man Gabriel Chavarria moves.

USMC Photo










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