I wonder how long it takes for a bear to recover from a snout full of pepper. I got charged by a black bear once, I was lucky that he stopped at the tree line and my porch/front door was 15ft from the tree line.... I was walking around my house and I could hear them hooting off in the distance and I was just kind of standing g at the edge of the trees where it gets very thick and I heard a lil bit of rustling around, then I smelled him, then I cocked my head over to my porch only to realize my porch was one trash barrel shy, and then the hairs stood up on my neck and I crouched down to get a better look through the trees and I heard a loud snort and then the sound of vegetation breaking, he was barreling through those saplings like a raped ape, I've never seen something so big move through thick brush like that but I moved with purpose and a will to live. I had a gun but it was so agile and fast that I think if it wanted me it could have got me.
Kind of like trying to get your seatbelt on before you wreck, it all just happened fast and I'm glad I didn't try to pull on this bear and instead made it to my door in 3 big bounds.... Bears are no joke, even big old black bears that you see lumbering through the woods and they look fat and slow, I assure you, they can take off like a bat out of hell. They are impressive animals. I think a 12ga is probably a safe bet, I think 10mm is probably better than nothing but I would opt for the 12ga because they can close distance very quickly and if your first few shots don't hit the light switch you could be in serious trouble....