Vulcan firing valve tension
Anyone know the correct way to set the tension on the Vulcan firing pin valve?
My .25 Vulcan developed a rattle from the end of the cylinder, just stripped it to find the spring and tensioner cover floating about loose inside the cylinder!
Looks like it could have done with securing with thread lock.
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there is always the on-going discussion about if it is ok to dry fire a pcp (to empty the cylinder).
if your return valve adjuster is way too deep and your hammer preload is huge, shooting the gun will damage the valve. yes.
under normal operating conditions the knock open valve NEVER opens fully i.e. more millimetres
this becomes critical only if your cylinder is empty/off reg
Yes, ignore the threads showing. The only thing people need to know is the valve pin to spring squish.
My threads aren’t even showing at all IIRC
For some reason I thought Evgeny was Czech, apologies Evgeny (if you ever read) anyway, he seemed to read Czech better than English.
if you look closely at the crossection picture, i can clearly see 3 threads visible from the regulator side.
for me it is more like the maker is saying check if the valve pin is not bottoming out.
my return spring adjuster is not that deep in.
by the way, the maker is russian, his production is where the embargo does not appy
in my understanding it does not tune much on a high power .25, go a bit more cw so it does not uncrew itself next time. if you overdo may be missing some fps.i remember zonk was saying his was 3 full turns and that was too much?
zonk were the 3 the numbers of threads visible?
you really want a few treads to hold it in.i dont remember seeing any visible threads so mine is not very deep in.
That I can’t say because Ernest did the work on it. He made a U-tube video using my Vulcan and how to set the valve if I remember right.
Note the firing pin has a slight dome to it, that should be proud while the outside is flush with the body as the spring is compressed solid.
Thanks, that is very helpful
Can’t access the link requires login
https://www.youtube.com/user/AirgunRegulators/videos
Might be worth noting that the first video doesn’t relate to the Vulcan firing valve. The Vulcan valve does not have the same entry as the one shown in the video and will not close up or be restricted when the spring is bottomed out. It has a series of holes round the outside of the tensioner cover rather than through a central hole.
a la..
I’ve pinned it in the tech section on bullpup mad forum
Don’t know for sure yet kris. I broke the sacred rule which says “Don’t fix what is not broken” and guess now I am possibly dealing with consequences.
was it yours drunk with the big SD spread because it was way too deep in? 😉
I did ask him if the spring being solid is so there is no bounce and he said “yes, that’s correct”.
I guess the valve coming to a stop against the spring prevents it flinging further inside the valve and wasting air and being able to bounce.
Please post the pics with comments james.
for anyone interested, in these videos you will find what tunes and how. around the knock open valve area and regulator.
https://www.youtube.com/user/AirgunRegulators/videos
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Interestingly I’d been using the gun with no preload on the firing valve (as the cover and spring were rattling around loose in the cylinder). Didn’t even notice any difference with the shooting, chronograped the same etc. I’d imagine it was no doubt more wasteful of the air though.
When I emptied the gun I expected it to dump the air really early, but it held on until maybe 60bar or so.