I'm actually with YoBuck on this one.
The focus shouldn't be on the caliber, but the where and your ability with it.
When I still lived in the mountains of Idaho, all of mine fell to a single shot from a slower moving 165gr Hot-Cor from my 308.
MOST of the "problems" with bringing down really any game animal is the shooters failing, then typically from a poor choice in bullets.

Lots of folks over here in the desert like shooting 300WM with factory 150gr Core-Lokt bullets. Those bullets are WAY to soft for a mule deer if you hit bone. They love to Splash, then hear stories about ultra hard shoulders, 900 yard shots running, scopes that were off.... You get the idea.

Unless you really can't put the creep on an animal, there isn't much that won't be at operational velocity beyond what most hunters are actually capable of shooting accurately. So build what you want, or that intruiges you.