cliff 87 Posted February 28, 2014 Report Share Posted February 28, 2014 Hi all, I have asked this on the air arms site but no help, i have had a good lad send me his Chrono to sort my air rifle out, the only thing is the power is going all over the place from 12lb+ down to 10lb, what could this be down too ?? Quote Link to comment Share on other sites More sharing options...
evo Posted February 28, 2014 Report Share Posted February 28, 2014 firstly , can you be a bit nearer the goal post,,ie what model Air Arms is it ie s200 s410 s510 secondly when you say it is chronoing all over the place is this pellet tested with a full air cylinder ie 190 bar also has any work been done on the rifle recently or has it been shooting ok and then just started jumping all over the place cheers Evo Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted February 28, 2014 Author Report Share Posted February 28, 2014 yes sorry i had the air rifle back of a so called friend that ****ed it up and left it on my door step for a hr, i took it all apart and got it working again, it is a air arms s410 .22 and i do take it up to 190 bar ,hope that helps Quote Link to comment Share on other sites More sharing options...
evo Posted February 28, 2014 Report Share Posted February 28, 2014 cliff by the sound of it mate it could be a number of things but the first thing that I would do is strip it back down and change ALL the seals, be extra careful when putting it back together, then put it back over the chrono with around 150bar in the tank and see what it is reading then, write down the results from a 20shot chrono reading , for it to be all over the place it could be numerous things but I would start with the seals first, don't forget to change the seal on the bolt also let us know the readings bud cheers Evo Quote Link to comment Share on other sites More sharing options...
turbo33 Posted February 28, 2014 Report Share Posted February 28, 2014 But first.........is it a combro chrono? If so make sure you fire the rifle with it horizontal as you would through any chrono. If you don't you will get erratic readings. Quote Link to comment Share on other sites More sharing options...
chrisjpainter Posted February 28, 2014 Report Share Posted February 28, 2014 But first.........is it a combro chrono? If so make sure you fire the rifle with it horizontal as you would through any chrono. If you don't you will get erratic readings. It's not! it's my Xcortech 3200. I lent it to Cliff, but first ran my Tench regged R10 over it and it's performing spot on , reading the same figures as my gunshop's F1 Chrony Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 1, 2014 Author Report Share Posted March 1, 2014 What I will do then is buy the seal kit off ebay if anyone know if they are anygoog, I only had them done last year by the shop. I do no that the seal as gone under the pressure gage I did try just puting a round one in it and is holding the air in but then the gage don't work, if its not the seals what do i look for then ? Quote Link to comment Share on other sites More sharing options...
NIGHT SEARCHER Posted March 1, 2014 Report Share Posted March 1, 2014 (edited) I would do a strip and clean and oil before spending money. I was asked to look at two guns by members of HFT club with a similar problem to yours. One was a Logun pro and the other a Daystate huntsman. On stripping them down one had a chewed up pellet in front of the hammer. And the other had shards of lead and other crud in the hammer slide slowing it down. The mashed pellet was stopping the hammer hitting the hit valve properly. And the other was the hammer being slowed down and not hitting the valve hard enough. After a very good clean and oiling and new hammer springs in them. Sorted. I set them both at 11.5 ftlb Bisley mags and they were consistent over 70 shots over the chrono. Edited March 1, 2014 by NIGHT SEARCHER Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 1, 2014 Author Report Share Posted March 1, 2014 Hi night searcher thanks for your post It as been the 2nd time this week i have strip and clean and oiled i did it last night, how would i know if i needed a new hammer spring, I just dont know why it is doing it Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 1, 2014 Author Report Share Posted March 1, 2014 just been and put 20 more pellet in it and got these readings 16.34. 16.74. 16.35. 17.07. 16.14. 16.55. 16.46. 16.05. 16.08. 16.85. All these are in Joules and not Ft/lb 16joules is 11.8LB Quote Link to comment Share on other sites More sharing options...
NIGHT SEARCHER Posted March 1, 2014 Report Share Posted March 1, 2014 (edited) Hi cliff. The hammer spring may feel a bit weak or the gun very easy to cock. I tend to put a new one in if the Rifle is a few years old or it`s had a lot of use. www.gunspares.co.uk A new hammer spring for your AA S410 is £3.58p. And a full seal kit is £4.45p. If you go to there web site there`s 3 pages of spares and an Exploded view of the S410. Ho **** 17.07 Joules == 12.6 ftlb It looks like your hammer spring is fine. It needs tweaking down a bit. Hit Valve or Transfer ports might be worth looking at. Edited March 1, 2014 by NIGHT SEARCHER Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 1, 2014 Author Report Share Posted March 1, 2014 hi yes i have just been looking at that site too lol what do you think it could be down to did you seen the out come i just got, would the seals make it go all over the place it dont sound like i have any air leaks Quote Link to comment Share on other sites More sharing options...
NIGHT SEARCHER Posted March 1, 2014 Report Share Posted March 1, 2014 It`s a mystery your getting a .75 ftlb difference over a 20 shot string. Ho **** 17.07 Joules == 12.6 ftlb It looks like your hammer spring is fine. It needs tweaking down a bit. Hit Valve or Transfer ports might be worth looking at. Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 1, 2014 Author Report Share Posted March 1, 2014 I can turn it down if i can get the same reading, what am i looking for i know where the hit valve but what about the transfer port Quote Link to comment Share on other sites More sharing options...
cliff 87 Posted March 4, 2014 Author Report Share Posted March 4, 2014 Hi all again I have asked this on air arms forum but will ask on here again, I have put the new seals in what come today but it is still shooting from 15.61 up to 16.03 this is in Joules 16 joules is 11.8lb the hammer spring seems fine what could i try next ? Quote Link to comment Share on other sites More sharing options...
pabs Posted March 5, 2014 Report Share Posted March 5, 2014 190 bar is too high a fill. Try a 160 bar fill and run it over the chrony again. Quote Link to comment Share on other sites More sharing options...
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