Brocock/BRK Another question/test for you all

[bchannell]

I pulled out my Brk Sniper 22 to do some shooting and noticed it empty.
When I went to fill it, the reg pressure went right up with the fill pressure, and way above reg setting.
No big deal, I'll reseal the reg.
I found some strange findings, at least to me. From the photo below
#1&2 orings look ok, at least they certainly didn't look like they were leaking
# 3, 4, 5 and 6 were in good shape
#7 looked great
#8 looked horrilble, aha! found the culprit.

OK, but then it hit me. If #1 went bad, the reg would leak out the bottom of the gun at the reg face
If # 2 leaked the reg pressure would go up as I describe above, it would match fill pressure
If # 7 or 8 leaked it would leak out the atmospheric vent, and likely would not overfill the plenum

I did not notice, and I checked, leaks at the atmospheric vent hole before emptying the rifle.

So my question is, if #8 is the only bad oring, how did it not leak out the vent and never pressurize the plenum?

 

[bigHUN]

Usually when I take anything apart on my pcps I replace every each oring on that given part, I don't even bother inspecting.
From a pressurized state to ambient pressure the oring rubber may or will morph, also some microscopic burrs can make things worse.
Otherwise I have no comment on this your Reg.

 

[sb327]

Was #8 extruded down the sides of piston? If so, it could have ‘locked’ the piston in place but still have sealed. This would keep the piston from moving and allow plenum pressure to rise with reservoir pressure.

Dave

 

[bchannell]

Was #8 extruded down the sides of piston? If so, it could have ‘locked’ the piston in place but still have sealed. This would keep the piston from moving and allow plenum pressure to rise with reservoir pressure.

Dave

That sounds reasonable.
I for sure will replace all the orings. I thought I had plenty, but did not so am waiting on more to come in.

 

[Trucker3573]

Over thinking…probably isn’t the only bad oring. Easy to just rebuild and be good to go. My only question is let me know if you find a source for the whole rebuild kit. I need that as I need the little delrin disk not necessarily orings. A of A out of stock forever and no way I’m paying what one costs with shipping from Huma. Can’t find a source. Assuming all the international shipping hassles stirred up by the ridiculous tariffs are why A of A hasn’t had any in forever.