I have not used much CO2 since I started practicing over a year ago, but had used up a 24 oz. bottle little by little during that time. When the bottle ran out I got it refilled and started working on a small project on a gun. I was AMAZED but in about 15-20 minutes the bottle was out. I was using a Classic at about 60 lbs. with a tungston piston. Could this heavy set-up, with higher pressure, be what drained the bottle that fast?