blank cell Model 1928 M-1A1
Stats listed on pg. 291 of the Delta Green sourcebook
COMBAT USE: US Armed Forces, British special forces

Perhaps the most well-made submachine gun of the war, the Thompson was noted for its accuracy and reliability. Whereas most submachine guns of that period were designed first for mass-production, the Thompson was designed to the exacting standards of a service rifle. Besides that it was expensive and difficult to produce, the Thompson's only real drawback was its heavy weight, though this did serve to reduce recoil.

While the civilian Model 1921 gained infamy as the "Chicago Typewriter" of Prohibition-era gangsters, the Thompson had always been meant for military use, and in 1927, a small number of Thompsons were issued to US Marines in Nicaragua. This model had a compensated muzzle, a horizontal fore-end and used a 50-round drum magazine, and in this configuration was known as the Model 1928. In 1938, the US Army adopted a similar version with a 20-round box magazine known as the Model 1928A1.

In 1940, Britain acquired the Model 1928, with a pistol-grip fore-end and drum magazine(top picture above), and issued them to their new commando units. After quickly replacing the drum magazine, which rattled during silent operations, with a 20-round box magazine, this model was adopted by the British for all forces.

Requiring an easier-to-produce model, the US Army adopted the Thompson M-1 in early 1942, which did away with the compensated muzzle, made the weapon lighter, and accepted only 20/30-round box magazines. The similar and even easier-to-produce Thompson M-1A1 (bottom picture above) appeared shortly thereafter, but the Army still required a submachine gun better to mass produce, and the Thompson was replaced by the M-3 "Grease Gun". Both the Model 1928 and M-1 versions of the Thompson remained in service with American troops throughout the war, and continued to be highly prized by those soldiers lucky enough to be issued one.