the shoulders and the front chest plate are strong on big hogs, and you'd be surprised how many big hogs i see take a shoulder shot, and when we finally find em, they are still alive and runnin 35mph away from us.
Bingo!
i have seen 175 pound hogs absorb 150 grain .30 caliber bullets that hit the shoulders and never even slow down. i've killed hogs that had wounds to the shoulder where bullets had come apart.
Double lunged hogs do not always fall dead where they stand. I have seen hogs hit in both lungs go 400 yards. Hogs are not predictable. Sometimes a gutshot hog will just fall over and die, usually they do not.
IME: The .50 muzzleloader seems to kill hogs much better than most .30 caliber rifles. One of my favorite muzzleloader bullets is the 240 grain .430 XTP. When a hog is hit low behind the shoulder that bullet sheds petals and lead. It shreds the heart, lungs and diaphragm. I now hunt mostly with the .50 350 grain FPB bullet. Hog fat is not going to plug up the two holes made by that bullet.
Good luck with your hog hunting.