Ive heard about less expansion at short distances with high speed. Idont think ive seen any proof of it though. Theres alit that can happen during a shot. Alot of different factors. You cant expect good results all the time. I shot a ptetty good buck with a 257wbymag ttsx, high shoulder shot. No exit wound. No blood. He reared up like a horse and fell over backwards dead. Front shoulder destroyed, back shoulder broke bad, the inside cavity of the deer looked like the bullet had exploded, everything turned to mush, broke ribs. That deer wasnt going anywhere.