The .308 does its best work with 150-180 grain bullets (though the 180s are excessively heavy for deer)...my favorite bullet for deer is the 150 grain Winchester Ballistic Silvertip...highly accurate and has performed very well for me even on shoulder shots.
For performance on larger game, I prefer the old 180 grain Nosler Partition usually from Federal's Premium line (anything heavier than this starts robbing the round of case capacity).
I have not tried the new performance ammo from Hornady nor have I used their Light Magnum ammo.