Originally Posted by ECAPNation
Tippmann style air restriction screw?
Would probably work, but would sacrifice efficiency in the process. Figuring out a way to put a palmer cart reg or CCI reg in place of the black 12g tube seems to me like it would ultimately be the best solution, but also not something that the average DIY-er could do. I'd imagine decreasing the pressure with CO2 would not only bring it field legal, but result in more shots per cartridge.