Why not just use a pistol?
Astute question. Future article.
Exactly, get something like a Taurus Judge. Shoots .45 colt or 410 bore shot shells. Varmit revolver right there.
My choice is a .410 pistol with #9 buckshot for snakes. There is also many useful loads for those pistols.
In a .22, the patterns through rifled barrels are terrible, useful to maybe 15 feet.
In larger calibers, with larger shot, not only are the patterns terrible, but the shot is dangerous to much longer distances. #9 shot can be dangerous to 60 yards.