6.5 CM served me well in the past five years. Harvest 4 coues deer and 2 cow elks, range from 300 to 550, all with one shot and quick death. I am now looking for a bigger caliber that has excellent BC and terminal energy. I am planning to use it for Bear, Bison and Moose. I'd like hear some suggestions, especially from someone had success on these ultimate big games.