Pump FSDO

[cellophane]

I took the pump out this weekend and it worked great other than have some wicked FSDO. If I shot several times in a row it seemed to be fine, but the first shot frequently just kind of blooped out of the barrel and only went 10-15 feet. Marker chronoed about 285; paint sized a little smaller than .680, and i was using a .680 Stella barrel.

Marker Info:
PsychoBalistics Superbolt: Inception Designs pump kit, Ergo HPR, CP ASA, Ninja ProV2- about 400psi output.

Any ideas on what would cause that and how to eliminate it? The only things that I could think of offhand are tank output pressure or getting some rollout from the breech.

[dano_____]

Regulator creep causes this. You may need a new reg seat/rebuild. It may have been slight roll forwards, but if you hook your reg up to an air gauge and let it sit awhile you will be able to tell if the pressure is slowly going up.

[cellophane]

Just looked at Autococker Parts and they have 2 kits- one with a degas piston and one without. Short of tearing everything down, how do I know which one I have? I'm fairly certain it is the non-degas piston but want to make sure.

[Chuck E Ducky]

Both will work. One is designed to purge air when you turn your asa off or remove the tank. The other will hold a shot until you pull the trigger. I suggest the Degas option unless you are running 12g.

[Tracker]

a super grimy bottom tube would contribute to some velocity issues, but not quite like what your describing

[Trbo323]

I'm with Dano, reg creep can cause a "sub door effect" which results in low velocity but any follow up shots have less pressure acting on the valve and therefore proper velocity

Throw that reg on a pressure gauge and see what happens after 20 minutes or so

Sent from my Moto Z (2) using Tapatalk

[spikeball]

I'll third the reg creep. Had the same issue you've having. Rebuilt the reg and all was well.