Off Regulator...? How do you know? Regulator pressure?

If you fill with a bottle (or hand pump), fill gun, close valve and let the fill assembly charged (don't bleed). Turn your hammer spring in to "over strike" so that you will know exactly when it comes off. Shoot over the chrony noting the speed and the pressure. When you get a drop in FPS you will know when the gun is off regulation.

Exampe

3000 - 900

2950 - 901

2900 - 900

2850 - 905

2800 - 900

2750 - 903

2700 - 875

2650 - 850

With the above string you would see the reg is set to about 2750.
 
x2 on what BTB said. When your hammer strike is well adjusted, the setpoint will be masked because you will get some number of shots of consistent velocity after the pressure falls below the setpoint. By deliberately giving it too much hammer strike, the velocity will begin to fall as soon as the pressure falls below the setpoint. Often times you’ll even be able to tell just by how it sounds…hmm, that last one sounded a little different.


 
If you fill with a bottle (or hand pump), fill gun, close valve and let the fill assembly charged (don't bleed). Turn your hammer spring in to "over strike" so that you will know exactly when it comes off. Shoot over the chrony noting the speed and the pressure. When you get a drop in FPS you will know when the gun is off regulation.

Exampe

3000 - 900

2950 - 901

2900 - 900

2850 - 905

2800 - 900

2750 - 903

2700 - 875

2650 - 850

With the above string you would see the reg is set to about 2750.

Thank you for the quick lesson!