I use my Ruger 22/45 with iron sights. Never seemed to need much more around here. If you sit still enough for 10 minutes you can knock over 1 or 2 under the same tree. Rarely a shot more than 20 yards.

I do want to try some Colibri ammo to try to get more than one or two without scaring the others away. Think it has the penetration power needed?

Chubber