7mm/08........
Shoot them through the lungs with just about any decent bullet, follow the blood for 40 to maybe 75 yards, and get your knife out and start field dressing.
I've used everything from Barnes X to CoreLokts and the result is about the same with the possible difference being that they don't go as far when hit with a softer bullet like a Sierra or a CoreLokt.

The 140 gr. Sierra Pro Hunter is the best in my experience.