I just purchased a S&W .44 mag with an 8" barrel for hunting. I saw .44 mag shot shells at the gun shop. Can I use those for squirrel hunting and will they damage my barrel by shooting them?
They are supposed not too. I have shot them before. They are really meant for snakes and such. You are not going to get any type of pattern out of it for squirrels unless they are really close.
I don't think they are going to hurt your barrel, but I do question whether they will have anything like an effective range for squirrels. My guess is that they won't give you an effective pattern beyond 15-20 ft. Get a box and pattern it at various ranges - it would be interesting to hear what you find out!
I've shot some of them over the years, and personally i think they are a poor choise for squirells... Like was already said, you need to pattern them, but the ones i shot had a very small shot size, and would be a poor choise on squirell size game animials...