Cricket velocity spread problem
Hi, I bought a used Kalibrgun Cricket recently and am having a problem with erratic muzzle speeds, best I have had from 14 shots was between 552 and 582 fps but have seen well over 100 fps spread on some series of shots, sometimes going into FAC territory.
My first thought was regulator so got a Lane Mk9 but it has not made any difference so wondered if anyone could suggest where to start looking for the cause of this.
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The tissues test, place a Kleenex over the receiver and make sure it covers over the pellet probe and barrel inlet into the receiver. Load up and fire ……..if it moves you have a leaky probe or barrel o-ring.
I’d try a new valve stem also.
Other than that it seems to be some what of a inconsistency issues with the springs.
Hammer, valve spring would be my bet.
Also why such a slow speed, between 552 and 582 fps ?
What are u shooting MK2 ?
My reg is set to 125 bar shooting 18g @ 880fps.
~ Greg
Thanks for the suggestions, been away a couple of days so they kept me busy a while last night.
Miksatx – Yes, new Lane Mk9, it’s .22
gku – could you give a bit more info on how to use tissues to test the O rings?
I am wondering about changing O ring size on the air cylinder where it goes into the block to something a bit thicker as was checking the valve spring retainer and thought the cylinder went back in very easily.
The valve spring retainer was in about 2 turns but 1 turn does not seem to make any difference.
It had a ‘huma’ reg in it when I took it apart to fit the Lane reg and sent the huma to xtxair for service and test and gun is still doing same thing when I put it back in. I am guessing the guy I got it off had had similar probs and changed to the huma reg.
It’s a .22, saw some hammer springs on ebay but thought a tenner was a bit excessive, I have found some that appear to be very similar, 10 mm OD and 1.5 mm wire dia at £3 for ten which I was thinking of taking a punt on. I have attacked it with the dremel to get the spring out and it is only 35 mm long, the ones on ebay were 57 mm, also been checking hammer etc., and all seems to move smoothly.
Tried new batteries in chrony last night but doesn’t make any difference, I did check it against a friends recently and very little difference between them. Spread on his HW100 is around 15 fps.
When I found the Lane regulator was not making any difference I asked them about it and they suggested a series of tests which are detailed in one of their guides, can’t find it now, that involved a few hundred shots all together as I ran them a few times and never noticed any significant change during them, I did notice first shot was often quite a bit lower than the rest of the mag.
Edit:
Check also the valve spring retainer, if it has backed out it should be 1 turn CW after contact.
Good luck ……
Hard to say ….
Use the tissues test to see if the Barrel O-ring or pellet probe O-ring needs replacement.
Poor crony fluctuation usually means u need to change out the smallest O-ring inside the reg …… but.
Check Hammer spring they seem to go bad sometimes.
Have a whole bunch of Hammer springs if it’s a 22 or 177 let me know.
Crony Battery change ?
Or do a long group shot to see a correlation proof with your data.
~ Greg
Was this a new regulator you just added? I’d think it might take a tin or so to break in? What ya think? By the way what caliber?
I changed the reg, also sent the one that was in the gun away for test and service and am told it was working OK.
Fps goes up and down, am not averse to a bit of meddling but I haven’t clue what could be causing this, from changing the regulator I thought it seemed a fairly easy gun to work on.
Think I’d start with the reg. Don’t know if you are a tinker. Does the fps climb each shot?
Which valve? There are no leaks from the main valve or the fill valve.
Did you check the valve? My have a worn o-ring.
Zonk
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Tried tissue test a few times but don’t see anything much, an odd slight movement that I put down to me moving or small drafts, is it usually very noticeable if there is a leak.
I am in England and we have some pretty draconian laws about most things that can be considered weapons, like a 12 ft/lb muzzle energy limit on unlicensed air rifles, the Cricket was fitted with an anti-tamper device, which was why I had to take the dremmel to it to get at the main spring and I am guessing the importer cut the main spring when they fitted the anti-tamper.
I’m also having problems finding a part supplier, the UK importer is very unhelpful, they just say send the gun to them and tried contacting Kalibrgun about parts and the problem but not had any replys.