M-3/M3A1 Sub Machinegun Grease Gun
by Tim Davis

In WWII the US Army was searching for a feasible replacement to the Thompson M1A1 sub machinegun. The military reviewed various plans, but they simply could not get the idea across that they wanted something lightweight and rugged, not something that looked good and had a stock made out of polished wood. The British Sten and the German MP40 provided a good example of what the Army was looking for. Frustrated, the Army took on the task themselves. They assembled a team at Aberdeen Proving Grounds and came up with the M3. The gun was made from stamped metal, fired a .45 caliber round but could also be modified to fire the 9-mm parabellum. The weapon was adopted and went into service in December 1942, and remained in first-line service until 1960.

A finger hole was drilled in the bolt which allowed the soldier to pull it back. This was the version my father used in Korea and I was first exposed to as a kid. Re-designated the M3A1, the gun was also modified with a magazine loading device attached to the wire stock. A flash suppressor could be fitted to both models. Some of the 9-mm M3's were also fitted with sound suppressors for clandestine use.


M3 Grease gun Army Ranger Weapon


Primary Function Close Quarter Battle
Manufacturer General Motors Corporation
and Ithaca Gun Company
Caliber .45 or 9-mm parabellum
Length
   ·Extended
   ·Retracted
 
29.3 in
22.4 in
Weight 8.1 lbs
Effective Range 100 m
Operation Blowback
Type of Fire Automatic
Muzzle Velocity 280 m/sec
Sight Front - blade
Rear - aperture
Magazine 30 rd box type
Cyclic rate 350 - 450 rpm