I have been out with DSL problems... I THINK I am back now...
Quick and others that said don't be so quick to judge... Jebus its ONE shot on ONE animal!!
I do like the 440WFGC bullet from Ranger Rick and it is the best for consistant accuracy from my gun. But that XTP if you have good accuracy should be a good one, at least all the XTP's I have shot performed very well.
I haven't shot near as many hogs as Jmayton, but of the ones I have I have seen but one bangflop on a pig. That was a brain shot my buddie did. I wasn't there but he video it. My 300gr with WW296 from a 45Colt Bisley.
From the sounds of your bullet placement, it was a heart lung shot, that will be a quick kill but rarely an instantaneous one. You have to hit bone for the electrifying bang flop. I like high shoulder or base of the neck if the game is close.
My 2cents of the the car penetration, its apples to oranges and to my mind proves nothing. Penetration, as long as its adequate, doesn't kill. (It is GREATLY prefered for good blood trail.)Shooting a boar, thru the lungs, with a 460 Weatherby mag and solids, (Insert any 45 caliber with buku penetration) or a 45 auto shooting 230 ball will both provide IDENTICLE results. BOTH will penetrate completely thru the animal. Both will kill the hog. Yet even though the 460 would likely do this to 4-5 hogs all lined up and the 45 auto likely wouldn't exit the second one. they both killed the hog in the same amount of time and distance. My point is, remove bullet diameter and expansion and a bullets lethality of same caliber is near identical. (as long as adequate penetration is achieved.) the 500 is 50caliber, the 45 is smaller and needs to expand to disrupt the same amount of tissue. The more tissue that's disrupted, the more vascular damage results. All equals a larger wound channel and faster kills.
I think your load is fine, shoot for bones and you will see faster incapacitation.
CW