Hi, I have shot hundreds of roe and some red, stags and hinds, with a .243. It will kill them all with proper bullet placement, but can cause massive carcass damage. I currently use three different rifles, one in 7mm rem mag, one in 22/250 and the other in .25/06. All ballistics (killing factors) depend on bullet type, weight and placement. Your .308 is a good choice, but again you need the right bullet at the right speed in the right place, as with ANY caliber.