Choices choices…
Ok, my valve seems to be doing pretty good but the fps deviation is a tad more than I’d like (14fps). I’m getting similar upper-numbers from both of the following:
10mm of spacer with a 100g hammer.
17mm of spacers with a 50g hammer.
Which config would offer better long-term consistency do you think?
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I’m done messing with this rifle right now. I’m just going to shoot it and take a reading each time and see how it goes for a couple of hundred rounds. The valve’s certainly not coming out again until it’s to fit the regulator.
I’ve done a 12-string, all good. No air blowing anymore, and I got a big fat crow with the last one which the cat is now enjoying.
LOL…Well congrats…..Whatever you did worked…Do you think the 2,300psi fill helped?
Are you mixing me up with Maw? 😆
Awe Man….Sorry…You’re right…
I’ve done a 12-string, all good. No air blowing anymore, and I got a big fat crow with the last one which the cat is now enjoying.
LOL…Well congrats…..Whatever you did worked…Do you think the 2,300psi fill helped?
Are you mixing me up with Maw? 😆
😳
That’s pretty damn sweet for the weight and psi. 😀
I’ve done a 12-string, all good. No air blowing anymore, and I got a big fat crow with the last one which the cat is now enjoying.
😳
Well I have a 20 string with the 42’s, my tank is low so I was short of my 2500 fill, the starting pressure right around 2300:
872
879
882
882
885
882
884
880
880
872
870
862
861
854
846
844
839
838
831
822
I’ll check ending pressure now 1800 ending. I wish I could of had alittle more air pressure to begin with.
I don’t have a tophat, I have a loose-fit collar that cannot vary once the breech is locked against it. It’s delrin though; I think I’ll make a steel one just to rule out possible deformation (clutching at straws with that idea).
I don’t think so, otherwise the inconsistency I’m getting would be consistently inconsisent instead of occasional. I get a good consistent string, then the next one goes to hell. High number followed by low number followed by high number etc. This is why I can make no sense of what’s happening, other than the delrin plug does something weird under pressure. But why doesn’t it do it consistently?
I have no confidence in my chrony right now, even though I think it’s functioning correctly. I have a springer though, so I guess I can put it on that and test it.
Could the delrin be getting hot and providing some sort of liquid state of
lubrication then cooling and attaching itself to the shaft?. WHat is the
amount of time between shots? Does time make any
difference? .Checking the chrony is a must…At this stage you need to
remove all the variables…..
These things are theoretically possible Mam, but massively unlikely. They might cause a first-shot anomoly if they were happening, but not up down up down, preceded by a good string. I thought possibly the nylon seal was sticking to the delrin plug if left for a while, but again that would be a first-shot problem I’d think. And I’ve done strings straight after a fill and a while after one and found no correlation to explain the issue. It appears to be totally random.
I should add that with the exact same valve design, but with the aperture cut straight through the brass instead of through a delrin plug, I’ve had none of these issues. So logically it has to be the delrin…but how and why? What could possibly cause a random inconsistency like this? There is not one single contact-surface that isn’t sliding like teflon under manual testing, and I’ve pushed real hard to try and find a snag or jam (hard enough to hurt my thumb). And that’s on the assumed possibility that under high-pressure firing conditions the stem could be pushed hard enough sideways to encounter such an issue. And if it could, why not every single time instead of randomly?
Sudden thought…maybe the forward breech o-ring is malfunctioning occasaionally and allowing air into the frame. That’s easy to test…
check the tophat gapp to make sure it isn’t moving out while sitting mine has done that before.
No, I’m not using lube of any kind. The delrin is slick as teflon and I can’t get it to snag or jam etc no matter how hard I try. I’ve put lateral forces on it that could never happen in normal use, it still slides sweet as a nut.
Everything I’ve thought it could be I’ve either ruled out with testing or fixed.
Jeeze, that would really piss me off to no end if my gun shot like that. don’t break anything no matter what you do, just remain calm, till help arrives.
I don’t think so, otherwise the inconsistency I’m getting would be consistently inconsisent instead of occasional. I get a good consistent string, then the next one goes to hell. High number followed by low number followed by high number etc. This is why I can make no sense of what’s happening, other than the delrin plug does something weird under pressure. But why doesn’t it do it consistently?
I have no confidence in my chrony right now, even though I think it’s functioning correctly. I have a springer though, so I guess I can put it on that and test it.
Could the delrin be getting hot and providing some sort of liquid state of
lubrication then cooling and attaching itself to the shaft?. WHat is the
amount of time between shots? Does time make any
difference? .Checking the chrony is a must…At this stage you need to
remove all the variables…..
I don’t think so, otherwise the inconsistency I’m getting would be consistently inconsisent instead of occasional. I get a good consistent string, then the next one goes to hell. High number followed by low number followed by high number etc. This is why I can make no sense of what’s happening, other than the delrin plug does something weird under pressure. But why doesn’t it do it consistently?
I have no confidence in my chrony right now, even though I think it’s functioning correctly. I have a springer though, so I guess I can put it on that and test it.
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Great idea….Enjoy…..