I'm also wondering where the 3000 PSI came from. Doing a little research on what threads are used for CO2, I find that carbon dioxide goes liquid in the tank, and that limits the pressure to around 850 PSI at room temperature. If the gauge on the regulator really goes to 3000, it may be a nitrogen regulator. If the GAUGE READS 3000 PSI, it's either screwed up, or you have a bottle of some other gas... I hope not oxygen.