I've got a TM Hi Capa I've done some stuff to over the course of time... aluminum slide, aluminum Outer barrel, reinforced nozzle, aluminum piston head, upgraded recoil/hammer springs, C02 mags. I've had no real trouble with it for the most part, but last time I was out on the field it would blowback, and then the bb would just roll out of the barrel. More research on this led to me 1. making sure the hop wasn't off (it wasn't) and 2. the nozzle valve was stuck. So I took it all apart, cleaned the valve and the inner nozzle, reassembled and it it shot like a dream... once. and then it stuck again. disassembling and reassembling did the same thing. shot once, stuck in blowback mode. Anybody encounter this before? do I just need a new nozzle valve, or is there something else that might be the problem?