me sniper musket just fell apart.

the valve started to leak, i looked at it and realized that the air had gotten under the rubber around the shaft of the valve and burst the rubber there, when i tried to unsolder the chamber cap something very weird happened, the chamber caught on fire, as if there was some sort of flammable gas continuously pouring out of it, and the solder would not melt, i ended up over heating it and the chamber melted.... but the solder was still untouched. i may be able to cut off about 2 or 3 inches of chamber and put another cap on it, but the gun will be far less powerful. does anyone know what kind of valve i can use? i need something that my shock pump can use, so not a presta, iv'e tried those and there great but when i take my shock pump off it lets all the air out. i'm gonna try soldering the schrader into a piece of threaded steel and bolting that to the airgun, but i don't know if i can get the schrader insert clean enough to solder.

i really need some help here guys.