But remember also, that people poaching to survive in the great depression weren't under pressure to make it count. They weren't like modern hunters who might only have one chance, to kill one animal, with one shot, once a year. (If that.) They didn't usually have big freezers to store a kill, and they didn't usually travel as far to hunt as modern hunters. They are looking for targets of opportunity, they aren't restricted by bag limits or seasons, and they aren't under pressure to take the biggest animal they can find. If they nick an animal with a .22, they will just wait for another one. Stealth and convenience were more important than clean kills.
Here's the thing about .22s. It's not so much that they will or won't do anything as much as they are UNPREDICTABLE. (All bullets are unpredictable, but .22s are much more so.) They MAY do a traditional wound cavity, or they MAY change direction because they have so little mass and energy they can get knocked around. When I was in high school, a friend of mine got hit right below the ribs with a .22 when we were out in the desert zapping jackrabbits. (We don't know who hit him. I know it wasn't me, I was reloading a 10/22 magazine when it happened, we think it might have been a ricochet.) It entered in the front, and exited out his back right below the ribs. We said a naughty word, carried him back to the truck, and drove as fast as we could to the nearest hospital, about 30 min away. He walked out 20 minutes later with two stitches and a band-aid, because the bullet had entered at an angle, skimmed the outside of his ribcage, and exited after having done a near 180. Like I say, we don't know if he was hit directly or by a ricochet, that bullet may have had reduced energy.
I think it is POSSIBLE but highly unlikely that a .22 can ricochet around someone's head. The sabot round from an M-1A1 120mm smoothbore can have this effect at the edge of its effective range. It doesn't have enough energy to scream straight through a target tank, so it will enter and spall, (push in a chunk of the tank's armor,) and the pieces will bounce around shredding the crew and touching off the ammo, but the circumstances where a .22 might do this would have to be perfect. I think most of the stories where they 'bounced around' in someone's head come from laypersons who just don't realize that any given gunshot wound may appear very devastating.