Impact experts please

[Keyman62421]

Gen One impact 700 Barrel power plenum, 25 Cal it quit shooting well I took her apart to the Bone checked plenum & valve, adjusted probe . reassembled she's shooting at 875 like a tack. regulator on 100 after 3 or 4 rounds she drops POI and FPS about 3 per shot . I quit @ 840! ( showed no sign of slowing the decent.
See no irregularity in reg gauges.
Some one has experienced this. How about giving me hint.

 

[Chuck-in-Ohio]

Only thing that comes to mind is C3 bumper going bad, c1 is working loose or possibly the reg needs rebuilt.

 

[Mrshosted]

Sounds like a c1 coming unscrewed or the set screw on the hammer adjusters need lock tight

 

[Lewis]

Agreed. I have experienced the same issue with a loose C1.

 

[Keyman62421]

I put purple lucite on cq yesterday. I'll check & c3. Thought it was okay yesterday! The gun is super quiet!
Don't find anything I'll pull the regulator