yhc:
Assumuing you plan to hunt the entire spectrum of Alaskan big game, I'd lean towards a 2 gun battery. Something on the order of a mid caliber rifle for sheep/goats/caribou and a larger medium bore for the larger animals such as moose & the large bears. I really like my .270 for sheep & caribou and would have to say that anything in the range of .27 cal (or maybe even 6.5 mm) up to & including .30 cal would be fine. For medium bore calibers, almost anything from .33 up to whatever you can comfortably & accurately shoot. I personally go to my .338 Mag for this. As was mentioned above, you don't want a heavy rifle to lug around on the sheep mountains. For moose, I could probably go as low in a cartridge as a .30-06 with a 180 gr. bullet. I've seen the '06 put moose down quite effectively but I'd prefer a larger caliber. In all cases,(except maybe deer) I wouldn't hunt up here with anything less than premium bullets. To me, that's a MUST.
Later, Bear in Fairbanks