So, I wonder when they are going to pass some laws banning Pit Bulls? I mean they seem as dangerous as guns to me based on what the media tells me all of the time but I have not seen anything on capital hill about the possible banning of pit bulls! Sorry, I had to. If you don't see the sarcasm here then...nevermind. Just to clarify, no, I do not mean anything bad against pit bulls or their owners in general, nor do I really have any problem with guns.
To the original poster, IMO, you did what you thought you had to do. I can tell you that Pit bulls are no joke and I do not play around with them based on some incidents I had as a kid. Do not ever let your guard down against one. Sounds to me like it was kind of a close call, playing or no playing, you did what you thought you should do. So, stand behind that. Considering you said you could not get the dog off it does not sound like it was playing to me and in all honesty I am not sure what i would have done in that situation but it sounds like you handled it well. I was not there but if it had been me and one attacking my dog like that then I might have shot it, I just cannot say without being there. As far as I am concerned attacking my dog is no different than attacking family. At the very least I hope you gave the owners a serious earful. I might have even called the cops as having the dogs off the leash is against the law, at least where I live.
Oh, and just for the record, No, I don't think all pit bulls are bad! I believe a lot of it has to do with how they are raised. I have some friends with 2 pit bulls and they are the nicest most well behaved dogs I have ever met, even more-so than my own dogs. However, I still do not let my guard down with them or any dog for that matter!