A military small & medium caliber ammunition collection

20 x 110mm HS404 United States

20 x 110mm HS404 TP  United States G.M.S. 1943 20MM M21A1. profile view.20 x 110mm HS404 TP  United States G.M.S. 1943 20MM M21A1. head view.

Details

TypeTP
Projectilesteel, aluminum windscreen, black, 1 copper driving band Driving Band Markings: GMI-1-1-129--53-20MM M99
Casebrass
Primerpercussion, flat, brass, 5-stake crimp
HeadstampG.M.S. 1943 20MM M21A1.
NotesThis may be a reload since the projectile isn't crimped, although it is very secure in the case.