It doesn't really matter much what you shoot a hog with if you put it right around or in his ear. Any centerfire with a decent bullet will do the job when you shoot them there. If you start shooting them in the body, then you will probably want somethng bigger than a 22 caliber because the wounds can seal up and make a hard tracking job. The last one I shot down south of San Antonio a couple years ago was with a Sako .243 right between the eyes at 85 yards and he went down without a squeal! I would have rather waited for a broadside shot in the ear, but I was losing light fast and he didn't want to turn.