Dos Perros
WKR
“Energy” doesn’t matter, bullet construction does. Use a hard cast or solid copper penetrating bullet and it will effectively penetrate whatever you hit. The key being “hit,” misses don’t count and a non-vital hit won’t stop the charge no matter what you’re shooting. The primary appeal of the 10mm is that it gives adequate bullet weight and velocity- but with double or triple the number of shots vs a revolver. In my one and only bear encounter, I fired 8 rounds of 10mm in about 2 seconds.
What evidence do you have to substantiate this?