There is probably no better medicine for NA big game than the 300 Win Mag and good 180 grain bullets. The 30-06 is dern near as good and the 270 is cetainly in the same ball park. I dont like the recoil so my limit is the 308 which is just as good. If I absolutely need something bigger, its the 45-70. A oldie but goodie like me, At least the oldie part.