Bullets are designed to destroy. How much destruction involves velocity at impact, bullet construction, and target.
I once jump-shot a pheasant with an ounce and a quarter of #6. I'm sure every pellet hit the cock because there was just enough left of it to throw it away. What a waste. I was a young pheasant hunter. Had I been wise I would have used an once and an eighth and would have allowed distance between bird and me before firing. It was a costly education.
I have had a few gnarly wounds using 150 grain BT's out of my 7MM Rem Mag. I'm going back (I should have never left) to my .270 Win for deer and almost assuredly elk.
I love my 7MM Rem Mag. It is a fabulous cartridge. But dead is dead. A .270 will destroy hearts & lungs just as surely as will any other big game cartridge.
Antelope have a hide that I found is pretty thin and prone to opening up like that exit wound, especially if any bone was hit going in or coming out. I shot a pretty buck one year with my 30-06 and 165 gr. Nosler solid base boattail at 500 yards. The bullet hit a rib going in on a shot placed directly behind the shoulder. It expanded well and went out the other side leaving about a 50 cent piece sized exit hole. The left side (entry side) had a hole in it that had to be seen to be believed. There was nothing but a hold that was about 4" from side to side and 2 - 2.5 inches from top to bottom. Ribs and everything was gone! Only thing I can figure is that the bullet hit a rib centered going in and it acted like a grenade and tore the surrounding hide and destroyed a rib or two on either side at the same time. Sometimes bone, hide, and animals just don't look like you might expect from a very good shot placement. It happens. I shot a spike bull another time at about 150 yards right through the lungs behind both shoulders. He ran about 50 yards and dropped. The entry and exit appeared as I would have expected. Performance looked great. When I skinned that bull I have never seen so much bloodshot in the ribs on both sides of this elk before or since. Sometimes it happens.