I never passed a shot at one for any reason with any gun when I lived where they live, even killed them with a shotgun and birdshot. Vermin is all they are to me, though I do eat them, they are too destructive to the native wildlife as well as agriculture to give them a pass. And I don't get too worked up if I loose one that runs off to die. Flame me all you want and I won't change my mind, I've farmed where hogs moved in and it isn't pretty.
A buddy did have good luck head shooting some pretty fair sized porkers with his 17hmr and the 20gr FMJ. He picked his shots precisely at closeish range and had an extremely accurate rifle. He was also hunting in a rimfire/shotgun only area. I'm pretty sure after seeing his results that an accurate 22 magnum rifle could be made to work okay in a pinch, using FMJ ammo and precise shot placement. I just had less than stellar results with the low velocities achieved in my handgun.
I did kill numerous beavers with headshots at ranges up to 50yds and the LR cylinder. Killed a running coyote with the LR cylinder and a single heart shot at 73 paces once too. So ymmv.
