Doesnt matter, as long as the caliber starts with a "4".
I have a couple of 1911 .45's, LOVE the caliber!
Never been a fan of 9mm's, used the beretta M9 in the service, big heap of crap. IMO its to small for humans let alone bigger and tougher critters. (some will laugh at this remark, but when I whack somebody, I want them down RIGHT NOW regardless of where I hit em).
Theres some real nice small frame .45's out there today if you interested in concealed carry and home defense. But, im not a very big guy (6 foot 150 lbs) and I have no problems concealing my GI model 1911 at the small of the back position.
Springfield 1911, LOVE it.
Colt 1911, LOVE it.
1860 Colt Army .44 cap and ball. LOVE it. (Tryin to kill a poochie with it this winter yet).
If you want to hunt with it primarily. Probably want to stick with the large frame revolvers, something in a .357 mag, or .41 and .44 mag.
The .45 ACP isnt really a "hunting" caliber. Its meant for human targets. However, it can be done, stick with the heaviest JHP bullets you can find and keep the range close, im more concerned with penetration with this caliber vs expansion, the bullet alone is already almost half an inch in diameter. Ive used mine to dispatch crippled coyotes before, and thats the load ive had the best luck with.