Well it depends on the bear a 800 lb grizzly .338 if a 300 lb black bear a 7mm or .300 mag will get the job done. But honestly I would probably take my .270 for any of the hunts he mentioned. But if I had the itch for a new gun it would probably be a .300 win mag. or a .375 H&H. Then I can go to Africa if the need ever arises. Might need to go take out some rogue cape buffalo or something.