Dave,
Lighweight is fine, especiallyin the mountains. But don't think of lightweight as also being a smaller caliber. I wouldn't go smaller than a .270Win and only then with premium bullets. Better yet a 30-06. Another to consider, a Kimber Montana in .308 - 5#'s 2 oz. or a Montana in 300WSM - 6#'s 3 oz..
Good luck.
