Elmer Keith recommended big bore rifles and to use them to take out the shoulders to stop a Griz charge.
In my opinion, it's possible to stop a griz charge with a 9mm about 1 out of 50,000 times.
The other 49,999 times the people attempting to do so will leave this world as a decomposing bear turd.
Elmer Keith recommended big bore rifles for squirrel hunting.