I'm very glad this helped out. I'm usually trying to find cheaper ways to do things just because I hate paying $15 for a hunk of plastic (Speed Feed... you apparently can use a Pringle's can cover and slice arms into it) and whatnot.
I did think about the pressure that can still be left in the gun... fortunately enough I haven't had to change the CO2 in the middle of a game. (Haven't taken the PGP into a real game yet... just casual games in the woods.) I didn't think that it could literally shoot out like a rocket. I was just worried about not losing the plug due to it unthreading...
