Why does the military use the .223?
*pound for pound, grunts can carry butt-loads more .223 ammo on their person than .308
*30 round magazines (usually loaded with 28)
*Lighter recoil than .308
*less raw materiel needed to make a cartridge
*volume of fire...although we did go to 3 round burst on the M16A2 didn't we
After seeing the steel parts of a HMMWV that can be penetrated through-and-through by ball ammo from an M16A2... I would not want to be on the receiving end of this round!
True, it ain't a .308, but the grunts turn to the M60 MG or snipers for that, and the tankers have the M240 coax.
After slogging many miles with M14s and M16s, and given the nature of "the threat", I will take an M16A2 over an M14 any day of the week.
Just my 2 cents, and worth just that!