The caliber you choose will be of little consequence but the detachable magazine idea is a great one. If u spend any amount of time getting in or out of a truck durring a hunt. I bought a 7mm-08 savage with a detachable magazine for coyote hunting near mountains I wanted to load some 110gr.bullets for the coyotes and have them in one magazine, and have a backup mag. loadedw/some 140 gr or larger for larger animals i didn't intend to call in.