Thompson M1A1
Type: Submachine Gun
Nations: United States, Philippines, South Korea, South Vietnam
Branch: Armed Forces
Time Period: 1942-1970s
Conflicts: WWII, Korean War, Vietnam War
Other Names: Tommy Gun, Thompson
Cartridge: .45 ACP
Info: The M1A1 Thompson is the final version of the Thompson series which saw the most simplification. On the M1, the charging handle was moved from the top to the side, simplifying the receiver from the M1928A1. There were also no accommodations to accept the drum magazines, the rear sights were simple stamped sheet metal, the stock was not removable and there were no foregrips, compensators or finned barrels. Although being adopted in mid 1942 and later being replaced by the M3 “Grease Gun” in late 1943, these would be used up until the end of the war and into the 1970s before being completely phased out in the US military.