I'd have no problem taking a .308 bear hunting in the Brooks. I've never specifically went after grizzlies with a .308, but that's just because I'm not big into bear hunting and I have other rifles that I prefer if I do go after bears. It's been over 15 years since I've bear hunted in the Brooks range, but I have killed two bears up there (used a .375 H&H), but I didn't own a .308 at the time. I have since bought a .308 and used it down on Kodiak this past year goat hunting, and although it wouldn't be my rifle of choice for Kodiak brown bears, I did kill a decent billy with it. After seeing how well it performed on that goat, using 150gr Barnes TTSX factory ammo, I would definitely feel comfortable taking it into the Brooks to chase grizzlies.