7mm Rem. Mag. and 300 Win. Mag. will do the job on all big game species, EXCEPT for the dangerous game. The big bears, like brown, Grizz and kodiak. When you go hunting for these critters you could be the hunted not the hunter. Many if not all outfitters for this animal require at least 338 Win. Mag. The most popular is the 375 H&H Mag. with 270 gr. for the first and second shots with a 300 gr. solid as backup. Your guide will probably be carrying a 458 Win. Mag. or better as a last chance solution.[:-]