Originally Posted by Uziel Gal
In stock configuration (in other words, if you have the stock reg spring installed rather than the LP reg spring), the Geo reg is intended to be used with an HP output air system, not an LP output system. That is why your reg out put pressure cannot get up to 135psi, and why you are having to turn your adjustment screw all the way out.
That might be contributing to your inconsistency (though a maximum variation of 15fps isn't horrendously bad), but that could just as easily be down to the reg needing to be cleaned, the solenoid's back check ball being dirty or damaged, the ball being too small (between 4.00mm and 4.10mm is optimal, and outside of this range, it is better for the ball to be a bit larger, rather than smaller), the battery being low, or the dwell being too low.
ok....thanks Uziel Gal! my ball is good (4.2mm) and my dwell in the 14.5 battery is new.... so i will to exchange my air system to the HP! try again!