I recall an article about a man who stopped a grizzly with one shot from a 9X19mm. Seems the bullet lodged in the one perfect spot in the shoulder to jam it up and prevent movement of the foreleg, thus the bear's face hit the ground and he skidded like in the cartoons. This doesn't make the 9X19mm a bear round, and most of us can't depend on miracles to save us. A .44Mag with 300 gr hard cast bullets would be a minimum if you're going to depend on a handgun to save your bacon. The BFR in .45/70 seems like a good choice.