No experience with bear but I was in South Africa for a week in April with 9 other hunters. I used the Federal Factory Ammo to kill blue wildebeast, wort hog, and smaller critters, one hunter shot through and through an eland. Of the 10 hunters all but one used a 375 rifle or encore handgun and of them all but one used the nosler, all performed very well. That being said for a big bear I think I would go with the 270 triple shock.