The M3 submachine gun, also known as Grease gun, was developed as a cheaper war-time alternative to famous Thompson M1 and M1928 submachineguns. M3 and M3A1 were developed and manufactured by General Motors Corp. M3 was introduced in 1942, and simplified M3A1 was introduced in 1944, and remained in service (in the USA) until 1960. M3 is full-auto only, blowback operated firearm. The retractable stock, made from steel wire, could be used as cleaning rod (when detached), it also featured a magazine loading tool. Some M3s and M3A1a were also fitted with flash hiders. The sights were fixed and were located at the top of the receiver.

M3A1 details
	Detail	Value
	Ammotype	0.45 ACP
	Clipsize	30
	Damage	65
	Inaccuracy	0.1
	FireModes	auto