Researcher and all, thanks for the info. Someday soon I'm gonna try to make up some .44XL shotshells and try my Stevens 101 out on cottontails with a little load of 4s or 5s. I've fired it with single.427 roundballs and seen no danger signs. It dates from the smokeless powder era and is chokeless.
I only mess with poisonous snakes when they are in areas frequented by lots of kids and dogs. We have LOTS of rattlesnakes here but they are really very unaggressive. You just need to know where they are and where your hands and feet are and make SURE they are not the in same place. And keep your kids and dogs under strict control (not a bad idea anyway). I shoot snakes when they get into or under buildings, including but not limited to outhouses.
Cottonmouths scare me, but then I'm a squeamish Yankee....