30-06!! I'd even go so far as to say that IMHO, the 30-06 with the 180 gr. Nosler Partition is suitable of any big game, short of those VERY big and nastys. Those extra 2-4" at 400 yds won't make a good shot out of a poor one, and a good shot can do it with either cartridge. Plus, I think those bullet weights of 200 & 220 grains could be a real advantage in certain circumstances.