Ya know, I'm a big fan of the .45 ACP, but it's the last thing I'd want as a primary weapon for hunting. Hell, for that matter, as a secondary weapon as well. The .45 ACP, regardless of FMJ, SP, HP, etc., wasn't designed as a hunting weapon; dear Mr. Browing intended it to be a defensive weapon against people.
If you have to resort to a secondary handgun during a bear hunt, you're already in deep do-do, and whatever you choose better be 100% capable of doing the job. I'm thinking a minimum of a .357 mag. stoked with 180 gr. hard cast Buffalo Bores.
Comparing the .45 to broadheads pushed by a 70# or more draw compound bow is apples and oranges. Broadheads are designed to kill large animals, and they do it very well. The stops may not always be quick, but any hit COM will result in death eventually.
I don't even have to think about this one; leave the .45 at home and take a few extra arrows.
--Capt. Charlie, who own & uses 3 .45's AND a compound bow
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