No one I know who hunts big bear uses calibers as low as some here offer up
Given most bears like lions are shot within charge range ....pinpoint pronghorn accuracy is not a factor
Energy displacement is
I have never been on a big bear hunt but I do read a lot.
There seems to be a rough agreement that the .375 H&H is the minimum for the large brown bear or Grizzly.
You still often read of guy killing them with small calibers.
Amen to that. Suggesting that anyone should hunt big brown bear with a .243 or similar round is very stupid and could end up fatal for those who take that advise.
Call any of the bear guides in Alaska and ask them what they suggest and what their minimum caliber is. I guarantee you that it will have a lot more energy than a .243. I can't figure out if advise like this is due to total ignorance or just plain stupidity. I'm a gunsmith, a life long hunter, and yes I have hunted brown bear and grizzlies. Someone was talking about 160 gr bullets as being heavy bullets. No they are not. They may be heavy for a, "undersized bear caliber" but they are not heavy for anything suitable for hunting big bear. Try a 338 wm pushing 220 gr or bigger and stay completely away from any bullet that does not expand. It seems that some people think that the lighter smaller calibers are more accurate than the bigger bore rifles. Not true at all. Take a look at what the snipers are using at 1000 yards + and what the 1K meter and 1K yard comp shooters are using. You will not find any small bore rifles in that bunch. I've also often been ask what it the best handgun to pack for emergency use in big bear country. That answer is simple, none. Pick up a cheap 12 gage and stoke it with it with heavy slugs sling it across you back and don't even go to the bathroom without it. Leave the handgun at home and pack more slugs. I'm sorry if I offended anyone in this post but even suggesting that it is OK to use a small bore rifle on big bears is just stupid.