I finally wrote up my full story on the 9mm bear incident and it's in the 2021 Gun Digest with numerous photos.
Before I carried I tested the Buffalo Bore ammo against known deep penetrating loads, including the 30 Tokarev, 357 , 44 mag and 475,Linebaugh and was confident it would work.

Power and bore diameter or great , but the ability of the shooter to make quick, multiple hits while under stress is of even more importance. Self defense , where the ability to make hits quickly while under stress, is not the same as stalking close and carefully placing a single hit on an unwary animal