Up here in Canuckistan we are generally not allowed to possess a loded handgun even on our own property, but when I go out checking trails and cutting firewood I carry a 12 ga with slugs on my quad, or my .44 mag with hollowpoints.
As mentioned here by others already.... proficiency and shot placement are probably most important than firearm type.
We run across bears and mama moosies frequently. From past run ins, I fear the moose to a higher degree as the bears usually don't want any problems.
They frequent our yardsite and as long as they don't return...they survive. Bears do what mother nature designed them to do so you can't blame them for how they react to situations, BUT they are more than capable of defensively 'swatting the head off your shoulders'...or injuring my grandkids playing in the bush around the yard. So I err on the side of caution and shoot 'loiterers'.
Oh, and we do have a dog, but sometimes the critters do not care about the dog's barking.
Last week the dog and I ran across a bear previously seen around the yard and treed by the dog (distinctive mink brown color). The dog and it went round and round trying to intimidate the other...both barking and woofing. I was ready to retreat when the bear focused on my direction, puffed up and began snapping its jaws. That was enough to remind me I had decided to dispatch it the next time I saw it.
I am have 40 yrs experience backyard plinking/target shooting with my model 29 - .44 mag, so I am not totally incompetent.From about 50ft I shot twice at its chest just down from its throat, without actually aiming fot its heart. It didnt react to the shots at all other than to dance a few ft closer to me. I shot once more and it turned and started to run, then folded.
I had assumed I had missed with the first 2 shots, but upon closer examination, there were 3 holes...not good groups, but all fatal.....but not placed for immediate incapacitation.
It was not a huge bear, either...about 300lbs.
I asume if it had been charging I probably would have missed in my target completly in the excitement. At least until it was chewing on my leg....then I would go for a head shot.
I have great respect for those who are actually competent when 'under fire'.