Can someone tell me the reason for this new caliber and gun to shoot it? Other then generals in Washington need to make it seem they are doing something constructive and of course open up the opportunity to get financial kickbacks from the arms/ammo suppliers buying favors. The 5.56 and M16/M4 have been around since the mid 1960's. Yes I am cynical. I only speak from being 72 years old and 2 years in Vietnam and using an M16. It worked.