Can't say I agree with the "any" CF right behind the ear will work thought. With many other things, just what size hogs AND also what sex they might be matters, whether some think so or not. A very large boar will have a shield of 1-2.5" and will affect any bullet from behind the ear to behind the shoulder.

Figuring hogs of 100 pounds or so, zero problem with any decent .243 load. Figuring hogs of 200- 500 pounds, not so simple, especially if they are boars. I've killed a very large boar that had a thick shield of no less than 2.5" and that also turned two bullets, 270gr JFN .44 mag loads from a Marlin Carbine and then required 3 more shots to kill him.

Again, small hogs are NOT difficult to kill. Large boars can be a chore and if they are not dead as you get close to check, you may have a surprise you weren't counting on or prepared to face.