I have used 60 grain Partitions and 55 grain Sierra Gamekings. Both will spit right through any deer broadside lung shots. Gamekings offer a more immediate kill while wrecking the insides. Partition out of my 22-250 shot through both shoulders of a 250+ pound whitetail at 15 yards and dug his antlers in the dirt. If shooting a 223 again I would go with Gk's in either 55 or 63 depending what the rifle liked.