I've used them in .38/.357; .44 Special/Mag. and .45ACP. At snake killing distances, they are supremely effective. Loaded in a revolver of 1911 they are just what I want when crawling around in the brush looking for a wounded deer, etc. In such situations blundering up on a snake will be up close and very personal. At such in your face distances, I have no interest in a single round that must be precisely placed. The CCI snake shot loads will shred just about any snake one encounters at hard off the muzzle range. A very nice added advantage is that after one pops off a round and nails the snake, a very quick double-action follow up shot may be fired with almost no time wasted dealing with recoil. As well, if the first round is not precisely on the head or some vital area, it will almost certainly be enough on target to greatly damage the snake allowing one to quickly fire another round with more precision. The cost is not unreasonable for what such a very specific limited use round.
If one wants to try it, similar ammunition can be handloaded. George Nonte wrote and article or two on the subject of producing such type loads using components as well as using standard and modified cases for firing shotshell type loads from revolvers and pistols.