Hey Zoinks...they only call it "the Grease Gun"..but its a 45cal sub-machine gun that was used by crewmen on Tanks...
These things were stamped steel and had about 5 parts to em, every part was interchangable with any other grease gun...
We used to take 10 of em apart and throw all the parts into a pile and then re-assemble them as fast as we could...then test fire em...
I think the ones we were issued in 84' came outta sealed creates marked from the 40's, and beleive me they had many many more still unopened at that time...
Tank