Valve lock/sticking valve?

[HubenK1Sniper92]

Here’s my problem, I have a war flex .22 rifle that I haven’t shot in about 2 weeks because of work, etc.. decided to shoot it today and it was all over the place and didn’t sound like it used to(power wise) put it on the chrony and it’s only shooting like 630fps, it was currently tuned shooting the 34g beast pellets at around 940fps.. what the heck happend? I had the reg set around 2300psi, I turned it up too around 3000 and pretty much the hammer spring adjusted maxed out and the best it will do is around 820fps? Does letting them sit cause this?

 

[Airmanator]

I have guns that been sitting over a year and they shoot just fine. Leaving it without shooting it does not cause valve lock. Especially only 2 weeks. Valve lock is cause by too much pressure that the hammer can't strike hard enough to open. If you are getting lower fps, maybe check for o ring damage or missing. Usually ppl lose the o ring inside the breech/barrel that seal the probe.

 

[HubenK1Sniper92]

I have guns that been sitting over a year and they shoot just fine. Leaving it without shooting it does not cause valve lock. Especially only 2 weeks. Valve lock is cause by too much pressure that the hammer can't strike hard enough to open. If you are getting lower fps, maybe check for o ring damage or missing. Usually ppl lose the o ring inside the breech/barrel that seal the probe.

I’ll have to check that, come to think of it the pellets seem to seat in the barrel easier now but I bad blown out breech seals on other rifles before and I always noticed a loud pop, this one doesn’t do that

 

[Motorhead]

Looks like a WAR Flex rifle ...
Is this a stock rifle or one that perhaps has been retrofitted with a JSAR Balanced valve ?

 

[HubenK1Sniper92]

Looks like a WAR Flex rifle ...
Is this a stock rifle or one that perhaps has been retrofitted with a JSAR Balanced valve ?

It isn’t stock, the prior owner said it has the cothran valve

 

[Motorhead]

Valve may require getting serviced with new o-ring/s
When an o-ring is used in a DYNAMIC function as it ages it can become extruded out of round and start getting along side the two parts in motion, when this happens you can get a lot of sticksion and ultimate leakage.

Also on a cothran ..
( I've read ) that when the strike from hammer is just marginal ( As in really not enough strike ) the valve can chuff less than typical output.
Check to make sure hammer is still free moving within tube and if it is may want to put is a tad more HST.

 

[Scotchmo]

Another possibility on the Cothran Powerhouse valves: The screw that holds the piston to the grate can start to back out. That allows additional axial movement of the piston. Valve can still crack open but will not pull open as much. If that’s the problem, I’d recommend at least blue loc-tite to hold it in all the way.