With a 68/3000 and LP mod, we regularly get 850 shots at 290FPS.
Without the LP mod, you can expect between 800 and 1000 shots per tank.
If you use a preset, you need a good inline reg like a Vigilante, Palmer Stabalizer of Gladiator whether you use LP mod or not.
If you have an adjustable, set it at 500 PSI into a stock setup or start at about 200 PSI into a LP marker.
With my present setup consisting of a 88/4500 centerflag, a Macdev gladiator and LP mod with volumizer and milled regulator housing, I get about a case as fast as I can pull the trigger with no shootdown.
Original Timmy Whisperer, Voider of Warrantys and Healer of Unicorns.
Petty Paintball - www.pettypb.com