Pressure drop

[west country warrior 0]

hi guys

 

after a little advice please. apologies if this has been discussed before (did a quick search and couldn't see anything)...

 

as with the title, have a HW100, and love it (if a little heavy), but over the last couple of months after charging to 200bar off a dive cylinder on a friday night before heading up to the girlfriends farm, come saturday morning with out firing a shot the pressure is down to 150bar. And by Sunday evening if left will be stone empty!

 

initially after charging and replacing the dust plug, then left for 24 hours the pressure would drop. upon removing the plug there would be some resistance and then a little 'phut' of air. this drew me to the conclusion that the cylinder seals were on there way out, so off to hull cartridge co for a refurb.

 

this was returned a couple of weeks back, and the dust plug is now a slightly different design, was returned fully charged to 200bar (which it maintained for 4 days-ish, until a free weekend allowed). after recharging it now drops pressure again, 150bar in 24 hours, near rock bottom in 48. but this time no back pressure building up in the cylinder against the dust plug.

 

Have also noticed when fired back to back against my brother in laws and his mates AA pre charge rifles i'm getting significant pellet drop and lack of range (theres are fitted with pressure regulators and chronographing 11.8ftlb) could this also be a sign/indicator?

 

has anyone come across this before? if so can you suggest possible problems and or cures?

 

any help very much appreciated, so want my baby back in 100% health for some more great lamping sessions!

[garfield 23]

get straight back on to hull cartridge mate it sounds like its leaking from the valving(its not really a regulator ) but they should sort it for you in no time hope this helps

[Marksman 934]

Sounds like the tiny cylinder o ring has gone mate. Wor kid had the same problem, we got some o rings off Adi at A & M Custom Gunsmiths fitted it now all sorted

 

Darryl

[garfield 23]

ahh forgot about the fact you can unscrew the bottle on these yupe then what he said

[west country warrior 0]

thanks for replies.

 

have cylinder off gun now and pressured up to 170bar. going to leave it overnight and see if its directly the cylinder, then a buzz to A&M me finks...

 

just out of intrest, once pressured up, how long should it hold it for/what time frame should it discharge it's self over?

 

apologies not had the gun long (second hand from my little bro, to gooda deal to miss after reading some reviews etc), more a shotty/bolt action kinda guy..

 

chris

[Marksman 934]

the cylinder shouldnt use any pressure at all mate

 

Once the cylinder is unscrewed have a look where it screws into the action there should be a small o ring I think that is your problem

 

Darryl

[RiffRaff 5]

sounds like the o-ring, but you could also have alook at were it screws in to the action the valve the cylinder screws on to might not be tight enough,, o-ring is a doddle to replace tho just pushes on might have to wip it out the stock if you cant get yah fingers in, i use a pair of plastic tweesers from a kids game to put the really small ones on

 

Niel

Edited March 2, 2011 by RiffRaff

[west country warrior 0]

thanks for all the help guys..

 

have had the cylinder charged to 170bar for the last 36 hours and not a drop in sight... so leads to the gun its self having the leak!

 

managed to find a strip and replace guide off an airgun forum, quick cut and paste into a word document with some piccies and print and i'll be off to the farm suppliers for about £6 worth of 'O' rings, the guy even attached a shopping list of the sizes handyly.. so allen keys ooot next weekend it is, and get this little badger all sealed back up again!

[Sweeney-Todd 208]

Hiya WCW.

 

HW100s......dont you just love em

Will send you a PM buddy, hope it helps you out.

 

ATB.

 

 

Bill.