I shot 140grn BT's out of my .270 and have shot many deer with them. Some went right on through without hitting bone, result dead deer, some hit bone and core separation occurred, result dead deer, some did both with complete mushroomed bullet retrieved, result dead deer. I think that faster these projectiles are pushed they tend to break apart. I now use 140grn Accubonds for all my hunting and have not recovered a projectile that has come apart they have either exited or are located on the hide. not sure how they would perform on thin skinned game like whitetail though.