interesting I’d always heard hogs/pigs had an extra bone in their forehead that deflected lower powered cartridges. So I wouldn’t have expected a .22 to do the trick. Especially after a young lady when I was in high school a long time ago tried to commit suicide with a .22 to the temple and lived when the bone deflected it enough.
My dad put three hogs down with three shots. I’ve seen on Swamp People that aligators have a hard head and you have to hit them at the right angle or it bounces off. Of course on that show they also say the kill spot is the size of a quarter.
I raised a few hogs is high School. Come butcher time, the guy came out, started his trough of boiling water and grabbed his .22, put two shots (with shorts) right between the eyes from five feet. The pig just stared at him, he loaded up a LR and that put it down. When he halved him we poked around the 1/2" thick skull and found the shorts just flattened out on the bone.