Saying things like this is just more ammo for the anti gun crowd. Guns are not destructive devices by nature. When you shoot a deer do you aim to destroy it or do you aim to kill it while otherwise not damaging the meat? When someone breaks into your home do you try to do as much damage as possible or do you first show the intruder you're armed so he'll leave before any damage is done and only fire if absolutely necessary? In combat you come across a man with 60+ lbs of explosives and shrapnel strapped to his chest in a crowded market. Do you aimlessly start shooting and hope for the best or do you take him down without setting of the explosives and save hundreds of lives?
Back to the large caliber fun! Legal or not bigger bullets are always better, rate of fire is just icing on the cake.
I was refering to the cartridge which is used in many weapons, not the actual M2 browning machine gun.