Two words: head shots.

but, re. this whole silly line on .45s: can you possibly concieve of how much game was taken all over the world with black powder loadings of .45-70, or .45 cal muzzel loaders? The ballistic performance of a modern .45 ACP is far greater than that wonderful old cartridge. As for the 1911, many, many of these weapons are more accurate than a trapdoor springfield ever thought about being.

The difference is the package and the shooter: can you hit a 4-6" circle at 50 yards over and over and over, If not, don't handgun hunt, if so, go for it.