Just FYI, that's a .45 cal. Submachine Gun, , M3, M3A1 aka a "grease gun" he's holding. Not that accurate but has the stopping power of a sledge hammer! A cool weapon to carry.
Looking closer I do believe you're right, vinylscrubber. Initially they appear similar. The Mp40 was earlier than the WWII M3 or M3A1 which was carried on at least into the Vietnam era.
[startquote from vinylscrubber]Not that it's worth arguing about, and I'm hardly the expert in firearms around here, but I believe Mr. C is sporting a German Schmeisser machine gun.