"The problem with "in the ear" is that it is rather vague. Here is a double, "in the ear" shot as well as a head shot. This hog should be dead three times. It was with a .308 hollowpoint. It was well less than 100 yards and was not effective. This hog had to be dropped while running and then finally a coup de grace shot was administered once downed."
....... To add to what Brian said, we went to my dad's for Father's Day weekend and my brother in law encountered a zombie hog for his first hog kill. It was about 130 lbs and about a 60 yd shot with a 6.8 spc/ 120 hornady sst. Took FOUR neck shots to finally anchor him (video tmrw.. Almost done condensing and editing the story/videos from the weekend). Here's a pic with his thumb, middle, and fore fingers over 3 possible entrance wounds. We think the obvious trauma on his neck was from a grazing bullet.
So if a 130 lb hog might need 4 neck shots (in rare circumstances, but nonetheless... I watched it happen fri night and will post vid tmrw) from a 120 grain .277 cal bullet traveling 2400 fps, then I'd say that a .22 mag isn't a great option, unless you're dispatching them in traps at close range or unless u can quickly easily and repeatably hit a quarter at 100 yds with one.