My time on POW was about thirty five years ago and things might be/probably are changed now. At that time, while not often, it was still occasionally possible to encounter grizzly sized blacks on the island. I personally witnessed the weighing (on LP scales, I assume to be accurate) a 440 lb bruiser that my pal had shot. If Phil says a .357 is adequate, then you could take that to the bank as gold advice, however, I would FEEL better with my .45 Blackhawk loaded hot with Buffalo Bore. That’s if you needed a backup at all, I’d just keep my rifle within close reach all the time. YMMV
