Choosing between a 7mm and 300 magnum is like picking heads or tails on a quarter. The animal you are shooting at will never know the difference. The result will still be a dead animal. 24 thousandths of an inch is not a whole heck of a lot to be worried about. 160 grain 7mm bullet vs a 180 grain 308 bullet. The difference at 400 yards is equal to a 17HMR. Not too much huh.