A .45 is gun enough if you put the ball where you want it. I took my first deer (that I didn't hit with a car) with a .45 Hawken, shooting a linen patched .445 over 75gr of 2F Goex. He was about 25 yards out when I squoze the trigger, and he ran about 20 feet before he piled up, dead as a hammer. Recovered the ball from inside the opposite shoulder blade.
This past November I took that Hawken out again with 80 gr 2F and a greased Maxi-ball conical I'd cast, mostly lead, but some wheel weights in the mix. I hit a doe just a bit forward, and she ran a few hundred yards, jumping both fences of my neighbor's horse pasture as she went. The bullet passed clean through. You can see the entrance hole in the photo with my dog, and the exit in the photo with the gun. Range was about 30 yards.
This past November I took that Hawken out again with 80 gr 2F and a greased Maxi-ball conical I'd cast, mostly lead, but some wheel weights in the mix. I hit a doe just a bit forward, and she ran a few hundred yards, jumping both fences of my neighbor's horse pasture as she went. The bullet passed clean through. You can see the entrance hole in the photo with my dog, and the exit in the photo with the gun. Range was about 30 yards.