does anyone have any info on these guns i have tried the internet with little success has anyone any ideas where i might find some good info ?

If you want to see one in action, watch the orginal "Jaws" movie...

There is a little info and a good photo of one in a recent article by Ross Seyfried. He said something about wanting to shoot a croc with one.

Jaws you say? I guess I don't remember that. Seyfried did say he wanted to shoot a great white with one but that it's not PC anymore.

Always seemed like a neat gun to me too.

I remember that quite a few years back, they were marketed here in the USA by H&R Firearms. Maybe you can scare up an OLD (1960's?)catalog!
Sorry, that's all I can give you.

these are still sold by navy arms in new jersey i believe. i haven't gotten a dealers catalog from them recently