I have 22 cal break barrels that tosses out Beeman extra heavy 21 gain pellets at 800-900 fps. The lighter ones get to 1000 fps. My preference for rabbits & squirrels is the Gamo ~15.5 grain round lead balls.
Nothing to mess with. They will shoot more than an eye out.
I used a Daisy pump up air rifle to kill 4 snakes in our implement shed earlier this year. 3 of the 4 were large rattle snakes. Did little or no damage to our barn.
Polish the barrel with Johnson paste wax, use the larger diameter BBs and it is very lethal. One shot between the eyes of a rattler, he dies instantly.
I have a Gamo Whispercat that excretes a pellet at the speed of sound.
The little sonic boom is very loud, even with the integral suppressor, which I assume is legal because, well, it’s integral. I bought it off Amazon.
It shoots through schools...of squirrels.