How Long Should A PCP Hold Air??

[Ronno6]

I understand that a PCP gun should definitely hold air.
But, should it hold air indefinitely??

[avator]

I understand that a PCP gun should definitely hold air.
But, should it hold air indefinitely??

Most if not all of my do. I had 1 slow leaker but it was sold.

[tennx]

I dont know about indefinitely……..and I cant speak to the notos as its new…….but 1358,urban 2 years and sentry 1 year…..knock on wood…good luck

[nervoustrigger]

For all practical purposes, yes it should hold air indefinitely.  Granted it is true that common O-ring elastomers are somewhat permeable to gases but it’s so slight that you probably wouldn’t notice it unless you’re keeping written records or leaving one idle for a year plus.

[anti-squirrel]

They should not leak, but they all will eventually.  Leaks will be caused by any of a number of imperfections in valve seats, valve discs, regulator seats, nicks in o-rings etc.  I base this on my experience with real HP systems for submarines, not the mini-systems we see in use on PCPs.  I should add this includes HP gas (air, N2, O2, etc) and HP hydraulic valves that saw PCP-style pressure on one side and atmospheric on the other yet they sat rock-steady for years.  Other valves that would get cycled very regularly but never ever not ever never never leaked.

And I also saw valves worth beaucoup bucks that couldn't hold air if you wined, dined, and treated them to ice cream.  Imperfections no matter how small impact these systems; air is a fluid and fluids seek the path to lowest pressure, always. 

[Back_Roads]

 My recluse has been holding air solid for close to 10 years, I expect that to change any day LOL

[Pellethuntr]

I have had my Discovery for around twelve years and I have replaced the o-rings due to a leak three times. I always figure that if one is leaking I might as well replace them all so I don't have to tear it apart a week later.

[avator]

If you think about it... unless you've degassed a gun or it leaked to zero, they've held some level of air since you've owned them. I have guns I've had for nearly 10 years and have yet to degas.

[anti-squirrel]

If you think about it... unless you've degassed a gun or it leaked to zero, they've held some level of air since you've owned them. I have guns I've had for nearly 10 years and have yet to degas.

My PR900 is one of those non-leaking PCPs, now that I think about it.  I've had to degas it each time I do any work on it (which ain't much).  For such a cheap rifle, it's been a winner excepting the putty-soft aluminum receiver and the original barrel. 

My wife's Lelya is another non-leaker; never been taken apart since I bought it used over 3 years ago.

[JimD]

My experience is relatively recent, I did not buy my first PCP until 2020.  Two of my guns have leaked, three have not.  My Avenger was fixed under warranty, it arrived with a leak.  My P35-177 developed a leak after I'd owned it about a year.  I replaced 3 O-rings in the front end of the gun and it is back to not leaking now.  I try to make sure I have O-rings on-hand just in case. 

I don't write down the pressure when I put a gun away, however.  If it seems like it fell I start tracking it and if it is leaking it will show a decrease over 24 hours.  I declare it fixed when it doesn't show a decrease over several days.  I know I've let guns sit weeks if not months and they still had plenty of air the next time I picked them up.  I decided to repair my 177 when I was out of town for a week and came back to a gun with nearly no air left in it.  Over a few hours the pressure drop was not big but over a week it went down over 100 bar. 

[tennx]

I will say this…Ive preordered a compressor….and unless a gun degasse over night ..as long as it will hold air for a shooting session Im good…will just add air as needed …@ the moment Im hesitant to have to repair one….lol..good luck

[avator]

I will say this…Ive preordered a compressor….and unless a gun degasse over night ..as long as it will hold air for a shooting session Im good…will just add air as needed …@ the moment Im hesitant to have to repair one….lol..good luck

Yep, those guns I've had in the past that just had a slow over night leak I just left as they were in most cases. I just aired them up as needed during shooting sessions. I may give them one try at replacing orings but if that didn't cure them, so be it.
Less than 30 seconds to fill them with the Yong Heng.

[anti-squirrel]

I concur with you guys... slow leak?  Meh, not a concern. 

If it dumps the charge fast or worse yet, instantly, I'll fix it. 

[avator]

I concur with you guys... slow leak?  Meh, not a concern. 

If it dumps the charge fast or worse yet, instantly, I'll fix it.

If it noticeably reduces my shot count during a string I'll address it.
If I fill it at night and it's zero by morning I'll address it.
If it loses a couple hundred psi overnight I'll let it go. Normally a leak like that will only drop so far and the hold.

[Ronno6]

Man says his Marauder won't hold air...
I put 2200# in it yesterday afternoon.....
Still has 2200# today............

[kbstingwing]

some hold forever, some hold for less, if it holds long enough it will due.... until I get bored, then I'll tear it apart as many times as needed...

[Back_Roads]

 If one leaks down in a month I know it will need attention soon, if it goes down in a week it get put up for repairs. Now that leaker tire on my truck can wait another year 

[Madd Hatter]

My Sumatra has held air for a couple of months. My sentry has never not leaked. My liberty has been a long fight but I think I've won that battle so far. Biggest problem with it is if it gets real cold the Orings or maybe just 1 Oring shrinks and it will lose pressure. Haven't had the impact long enough to know what it will do but don't expect to have any problems.

[3crows]

My expectation is that a gun should hold air pressure. If it is 3000 psi one day then a month later it should still be 3000 psi, ambient conditions might cause a small deviation due to temperature.

[StockClassDD68]

Yup, most, if not all of my pcp airguns hold for as long as I've owned them, ranging from 6 years to 6 weeks. Simple designs with quality manufacturing practices tent to do well I'm my case. My .22 taipan vet and leahiy classic have both been great for 6 years, fingers crossed I get another 6 years!