The M3 became the main submachine gun over the Thompson for the U.S. and South Korean forces during the Korean War, because the Communists used the Thompson submachine gun, which the U.S. donated during World War II, as one of their main weapons during the war.

Nov 28, 2020 · Watch this "At The Range" video segment above to see American Rifleman Field Editor Martin K.A. Morgan shoot a World War II-era M3A1 "Grease Gun" submachine gun chambered in .45ACP.

Feb 24, 2022 · Commonly called the “Grease Gun” because it resembles the mechanic’s tool of the same name, the M3 first rolled off the production lines in May of 1943, seeing its first combat during the Normandy invasion a year later.

May 20, 2016 · The new variant, standardized as the “U.S. Submachine Gun, Cal. .45, M1,” dispensed with the unnecessary and over-engineered Blish locking system of the M1928A1 Thompson.

May 20, 2024 · Just about every military small arms enthusiast is familiar with the U.S. M3 and M3A1 submachine guns, better known by the nickname bestowed upon them by GIs during World War II, the “grease gun.”

Designed as an inexpensive replacement for the iconic Thompson submachine gun, this utilitarian firearm overcame early reliability problems to capably serve U.S. forces and their allies for over half a century.

Apr 14, 2017 · The M3A1 Submachine Gun was officially “replaced” by the M-14 Rifle in 1957. The Grease Gun held on because even when the bugs were worked out of the M16 the Grease Gun did things that the M16 couldn’t do.

May 27, 2018 · Here's a look at the M3/M3A1 'Grease Gun,' a .45 ACP full-auto submachine gun that delivered for the United States and its allies.

Oct 1, 2002 · The M3 and M3A1 grease guns are the only U.S. weapons adopted during WWII that continue to serve even today. Some weapons like the famous Thompson Submachine Gun endear, while others like the utilitarian M3-M3A1 grease guns simply endure. This article was excerpted from the book The M3 and M3A1 Grease Gun.

The .45 caliber M3 is an automatic, air-cooled blowback-operated weapon firing from an open bolt, which is driven forward by the recoil springs, stripping and chambering and firing a round in the same motion. The M3A1 is an improved, simplified variant of the M3.