HST adjustment
Well, I did the delrin replacement for the brass piece a couple weeks ago. I also did the o-ring mod at the same time. Anyway, I counted the revolutions when I removed the HST adjuster. I thought I put it back right but it seems the head is deeper into the action than before – not sure. This is on a 22 caliber. Well, yesterday I had the opportunity to chrony the gun. When I got the gun, Tony sent chrony results that averaged about 930 with 18 gr jsb. We further adjusted the gun to get it back to 930. Now the head of the HST is pretty far into the action. Is there a possibility that it is screwed in too far but gives the same fps as a looser adjustment? Whereby I’m simply loosing too much air? How far in do others have theirs on a 22? Flush, 1/8 inch, 1/4 inch, 1/2 inch?
How should this initially be adjusted? Should it be simply screwed in until flush with the action, chronied to see where it is and then make say 1/2 turns until it is back up to 900 plus?
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I think I may soon be attempting this. I’ve ordered replacement o-rings for the gun and also for the bled screw mod. Hopefully, they will arrive next week and if I have time I may tackle this next weekend. Really didn’t want to randomly adjust the regulator and test – lots of time involved to determine setting this way. I have sent PM’s to reg tester builders to see if any are available and at what price. Not sure I want to spend a lot for a 1 time 1 gun brand purchase. Sure would be nice to have a universal tester. Is there such a thing?
Regarding how the gun shoots now, I’m not a very good shot but I’ve been hitting / removing “gumballs” (sweetgum tree fruit) from a tree about 80 yards away and 75 – 80 ft high about 4 times out of 11 shots. Pretty impressive to see the gumballs shake when hit and better to see them fly off. Using a MTC Connect 3-12X 32 scope with SCB reticle. Probably could do better if I had higher magnification but I really like the Connect.
Benj If you are considered that your regulator is set to high let´s say 160bar it´s easy to lower it. Simply open the bleed grub screw after your cylinder is empty. Then remove the regulator and make 1/4turn CW with regulator setting screw. Back regulator to airtube and check the status.
I did it couple of times without reg tester and I was always successful.
That doesn’t look good at all. I’m confident you’ll get better results with the AA.
All the top FT guys here have gone over to AA. Very uniform stuff.
I hope they arrive on 28.12 till end of year… I enjoy to them. And I always cleaning the barrel after pellet changing. 😉
Whatever. Get the reg down and try 16 fr pellets instead.
You , and your Gun , will thank me later.
I’m not trying to get 930 out of 18 gr. I’m trying to get a flat shot string. It appears the fps and flat string are dependent on reg pressure. Based on several strings my reg is about 160. One string suggested 180. Maybe I misread or that was a fluke. I don’t know. I haven’t adjusted the reg from factory setting. Seems like a lot of trial and error without a tester.
Haven’t you got them yet ??? Clean the barrel before you try them. They might be disgusted by the JSB lead .. 😉
That doesn’t look good at all. I’m confident you’ll get better results with the AA.
All the top FT guys here have gone over to AA. Very uniform stuff.
Hi Ville,
today I shoot some older pellets 1,03g/16grain
I tried various speed from 270-282mps but result is terrible.
I´m curious for AirArms pellets 
what would be the power if the reg was permanently open? anyone seen an unregulated power curve of a Vulcan?
Guokyotoyota is right about everything. You 18 gr afficionados should understand one thing though , and i repeat myself here : The gun is thought out to shoot 16 gr pellets at 930’s. Not 18 gr. If you have to use 18 gr ( i don’t know any good reason to that though ) then the reg needs to be set at unnecessary high pressure. Less shots / fill.
is that a coming off reg spike at all? … almost looks like as if your gun had two levels of power hehehe some kind of flow problem
you really need to see what is the reg output when the input is 90,120,150,180,210bar.
turn the reg down a bit to 120 and let us know if it helped.
Thanks for the information but I have a 22. I wonder how the hammers are different.
Hi benj397
Just my cents worth. I have a personal e mail from Pigrov Evgeny stating that a new free hammer will be available on request at the end of Jan 2016 for .25 owners. Curing spikes in Shot string. Seems worth waiting and chewing the cud in the interim.
Merry Xmas to all
EDIT: Well I was responding to a post from Kris after my last post but it is now gone. How do posts disappear?
I’m not sure what you mean. I’m trying to set the HST so that I get a flat shot string before it falls off the regulator and fps simply drops. As in this thread:
http://talonairgun.com/forum/viewtopic.php?f=54&t=33544&p=343949#p343949
This should give the most consistent shots while not changing POI. And by having it set this way, I shouldn’t be wasting air so I should also gain more shots per fill theoretically.
I have plenty of spring adjustment – it isn’t collapsed.
I haven’t changed the reg at all – still at factory setting. Don’t want to go that deep into the gun. Would prefer it to be 120-130 range to get more shots.
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It looks like John hagen is working on getting a universal reg tester built. Check him out
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