hi can anyone help please have a 30ft lb huntsman in.22 hardly done any work less than 150pellets from new,last week filled up with air put gun away came back next morn and all air gone zero pressure.tried to re fill and air just seems to be leaking out from trigger area,so was wondering if seal gone oe possible pressure valve stuck open any ideas please and anyone know where I can obtain a manual to repair gun from thanks jinksy