I have killed several with my GP 100 and CCI snake shot. It never took more than one shot. Killed one with a Taurus Judge using a 2 1/2 in .410 loaded with #6. Dead right there, no twitching. My 1911 with a CCI shot shell worked well, too. One shot kill at 20 ft. 9mm shot shell works well, too. All the above hang kinda heavy on the belt.
I have considered a small .38, but a man I know only uses his Bearcat to shoot snakes. I wanted to hear how the .22 worked for others who have used it. I've only used the .22 on mice.