Many many years ago in the late 60's or early 70's I read in article in (I think) Western Outdoors. It was about a woman trapper somewhere in the West around the 1950's or so. She was checking her traps and carried a .22 semi-auto rifle to dispose of any critters caught in her traps that were not dead.
Upon reaching one of the traps, a huge Grizzly stood up behind a bush. She emtied the .22 into it's skull and killed it. Turns out they found like 12 holes in it's skull. The story said the bear was a Plains Grizzly, thought to be extinct in recent past when the Buffalo ran out. That was their main prey. This bear then was one of the largest ever taken. The Plains Grizzly was common around the Los Angeles area about 10,000 years ago and several species are shown at the La Brea Tar Pits. They were able to kill giant ground sloths, large bison and even small mammoths or mastodons. Just about anything they wanted to eat.
I'm wondering if that isn't the same bear you you mentioned, Eddie? It would interesting to find out, assuming the article was true.