Great. How effective is a 357? I carry one.
Effectiveness depends on what load you carry and on shot placement.
What you want is a full power .357 load with hard cast lead bullets for deep penetration, like these: https://www.buffalobore.com/index.php?l=product_list&c=162
What you do NOT want to use are semi-jacketed hollow points, like the kind you would carry for everyday self defense. The key to stopping a Grizzly is penetration, and a hollow point won't give you that.