I whacked my first deer with a frontal chest shot using a 150 gr Hornady Spire Point at about 25 yards. The recovered bullet weighed 33 gr and the rib cage was full of shrapnel. Went to 180 gr bullets of same make/type and haven't had that particular problem since. However, that was out of a .30-06. My load development with 165 gr 180 gr bullets in .308 seems to show both at about the same velocity. Slight edge to 165 gr I guess.
If you've gotta go lead free, the Hornady all copper bullets do well in my little 7 x 57 mm carbine. But I haven't managed to get a deer to cooperate yet, so no performance report.