I had an M3A1 hanging next to my driver's hatch on my M113A1 back in '68. I never did have an opportunity to actually use it in combat, but when I did dump a couple mags through her, she ran just fine. The mags were a major pain to reload, even with the round depressor built into the wire stock ... and 30 rounds of .45ACP is HEAVY! I had a bag of mags ... must have been 8-10 and THAT was a heck of a load ... good for Mech units only ... hate to have to pack that load as a leg Infantry guy!