A European Informational Website
learn more
The M3 "Grease Gun" (more formally United States Submachine Gun, Cal. .45, M3/M3A1) was a submachine gun developed by the United States during World War II as a cheap substitute for the Thompson. It was nicknamed the Grease Gun because of its resemblance to an automotive grease gun, as well as for the fact that it contained an oil reservoir in the grip.