A .45 would work but hubs said you gotta be up close. And it could be messy. (.22 is .22 of one inch, .45 means it's .45 of an inch. A .45 is twice the bullet size)

.22 is smaller hole and cleaner. My hubs father killed 100's of cattle Brahma/Beefmasters type with a .22 long rifle for his meat market slaughterhouse. (also horses but obviously not for meat lol) Cattle have thicker skulls than horses. When I was a kid my dad also used a .22 LR for our Herefords and a few horses over the years.

ButIWantedAPony wrote:
I'm pretty much dead inside.