The Thompson submachine gun, with a delayed blowback operation, was designed by General John T. Thompson in 1921. It was immediately put to work by military and law enforcement organizations around the world. The Thompson's high rate of fire of the .45 cal. ACP round gives the weapon tremendous stopping power. The Thompson was issued to airborne, armored and reconnaissance units among others.
M1928A1 Thompsons, Fort Benning, Winter 1941 Photo courtesy of Gabriel Benzur whose father took the photo. Thanks to 'NaMe LeSS' for correct ID of the Thompsons.
Two Marines, Davis P. Hargraves with Thompson submachine gun and Gabriel Chavarria with Browning Automatic Rifle (BAR), of 2d Battalion, 1st Marines, advance on Wana Ridge, Okinawa on 18 May 1945.
M1928 and M1928A1 Thompson Sub-Machine Guns
The M1928 Thompson Sub-Machine Gun ("Tommy Gun") was adapted from the civilian model of 1921, but with a rate-of-fire reducer. It has a vertical fore-grip, ribbed barrel and top-mounted cocking lever. The M1928 was the first Thompson purchased by the U.S. military in quantity, primarily the U.S. Navy and Marine Corps. The M1928 was replaced by the M1928A1 with a horizontal forend, removable buttstock, and swivels for attachment of a military sling. It was selective for semi- or fully-automatic fire with the .45 cal. ACP cartridge in 20- or 30-round magazines, or a 50-round drum at a rate of fire of 600-725 spm. It had a leaf with aperture notch battle sight.
The M-1928A1 was relatively heavy, and expensive in use of materials, machine time, and machine tools. Records indicate total production of 562,511 by the end of WW II with production variants stemming from the M1/M1A1 design, including a fixed rear sight without the triangular sight guard wings and a non-ribbed barrel.
M1 & M1A1 Thompson Sub-Machine Gun
Thompson Submachinegun, Cal. 45, M1.
The M-1 / M-1A1 was also a blowback submachine gun, selective for semi- or fully-automatic fire. It fired the same .45 cal. cartridge in 20- or 30-round box magazines with a rate of fire of 700 spm in full automatic mode. The gun was reliable, and continued to operate when similar weapons would have failed due to exposure to battle-field conditions. Production was 354,000 weapons.
The M-1 Thompson was a redesign of the model M-1928A1 to simplify production. The M-1 had a permanently attached buttstock and a spring-loaded firing pin like the M1928A1. The M-1 would not accept the M-1928A1 drum type magazine. The M-1 had a simple fixed aperture rear sight.
The M-1A1 differed from the M-1 only in having the firing pin machined into the face of the bolt. The M-1 and M-1A1 models of the Thompson were developed by Savage Arms.
The loading lever is in a horizontal position on the right side. The butt is fixed in place by two screws. The Thompson is 32 inches long and weighs 10 3/4 pounds. It has a muzzle velocity 920 fps (feet per second).
Paratroopers commonly used a 20-round magazine. By the time the M-1A1 was in production, the 30-round magazine was common. Manufactures of this weapon were Thompson, Colt and Savage. The USAF had a holster assembly for the Thompson.
Recommended Books about the M1 & M1928 Thompson Submachine Guns
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