HW100 hell, help needed!

[Rgrc29]

Ok, so mine hasn't been the tack driver it's supposed to be, ever.
I fitted the adjustable hammer kit on a year or so ago, to try and tune it, no joy.
I've taken it apart before christmas to clean and oil the hammer assembly, and have had absolute hell since.

Initially it was using loads of air each shot, and then vented and wouldn't refill.
Bought a seal kit, carefully disassembled the valve mechanism (except the regulator, no tester, so left this as it was) and replaced some knackered looking o rings.
Hey presto, it holds air, and fires again!!
But now shooting at about 8 ft/lbs, very consistently, never has it been that consistent, very small variation in the shots.
Attempted to return it to normal power by tightening the hammer spring, nearly got it to the right power (11.5 ft/lbs) when the hammer spring being screwed tighter starts fouling the cocking lever as it's closed. Wind it back half a turn and the bolt can be closed again, but power at 10 something . . .
Ok, bit of research, need to raise the regulator pressure(?????!!??) only by a tiny amount, and then i can balance it back down winding the hammer out again??
I do this, and get it to 11.5 ft/lbs, but the consistency has gone now, its all over the show.
I'm fed up and **** off by this point.
Left for 2 days, no air loss.
Day three, down to 50 bar, attempted to refill and it vented again :-(

Just taken it apart again and found a crushed o ring, replaced and rebuilt the gun. It holds air again!!
But back to 8ft/lbs, and not consistent.
Inched the regulator pressure adjuster in a little more (im talking maybe 1/15th of a turn) and start balancing with the hammer.
It's now running at 8ft/lbs when the air reservoir is at 180bar (my bottle is now running low from all this messing about), and as you get down to 110bar its nearly over the legal limit?!?!?!


I'm running out of options and ideas, and patience.

Help!?

[Jesim1]

I'm no technician, and you have already gone beyond what I could do, but in saying that, it also sounds like you have run aground yourself.

I think you may save yourself a lot of time and hassle by looking up a fairly local repair centre who can sort your issues out. Regs can need special skill to set up as well as tools, and since you have had the gun in bits several times now it could be something is wrong your just not seeing or the reg is just toast and will never work? So you could be totally wasting your time here? My main point is - you don't have a problem that someone can just say - replace x/y/z and it will be fine, it sounds like there are several problems combining to give you a general headache.

I know this is not the answer you were looking for - but it would solve your problem in an effective and less frustrating way.

James

[Knockedover]

Have you owned the gun from new and can confirm it hasn't been messed with? I recently had a basket case HW100 come to me for fixing and once all the various leaks and bodges had been sorted the power and power curve was awful, very low from a fresh fill and gradually climbing as pressure fell. I did a reg strip and rebuild and someone had stacked the Belleville washers incorrectly which had effectively increased the length of the stack and halved the pressure needed to compress them. The result was low reg pressure, giving low output,with no real adjustment and then it locked the reg open giving a horrendous power curve. Restacking the Bellevilles correctly fixed it straight away, proper reg function and consistency

[lensman57]

I bet that the REG is either knackered or it has been messed with and not put back together properly.

A.G

[Rgrc29]

I bought the gun new in jan 15, besides the anti tamper being removed I've left it alone.
The only thing I've not disassembled is the regulator, as I don't have the guage to set it back to the right pressure.
Thanks for your thoughts and feedback, I was hoping to avoid sending it off somewhere as that'll be a few hundred pounds I didn't really want to spend :-/

[Rickenbacker]

I'm usually the last person to mess about with a reg' (because I believe among other things, they can contain ghosts), but the HW100 reg' is just a chamber containing a stack of belville washers.

The only HW100 I've ever worked on (an old MK1 version), I found the reg' chamber half-full of rusty water - which was odd.

[Knockedover]

I bought the gun new in jan 15, besides the anti tamper being removed I've left it alone.
The only thing I've not disassembled is the regulator, as I don't have the guage to set it back to the right pressure.
Thanks for your thoughts and feedback, I was hoping to avoid sending it off somewhere as that'll be a few hundred pounds I didn't really want to spend :-/

If you're competent enough to reseal an hw you're competent enough to do a reg rebuild there is very little to them. Best fitting does a reg tester for under 30quid and there is a couple of very good instructional videos on YouTube. It really is simple, a few o rings and a bit of spare time is all it takes

[Artfull-Bodger]

Ok, your chasing your tail,
First off there is a set sequence to assembling a HW100, and you MUST have a reg tester to be able to set it up, you can't guess.

You need one of these - http://www.hw100tuning.co.uk/Regulat..._15939020.aspx

This guy gives a good run down, not perfect but its pretty good- /forums/showthread.php/182879-hw100-stripdown-service

There are a few things you need to know which make all the difference,

Install the barrel LAST, the firing valve cap must be seated and torqued up before fitting the barrel, this is due to the barrel retaining screw being set at 45 degrees and pushes the barrel against the firing cap to seal it.

the air cylinder needs to be tightened up correctly , which means the brass valves and the collar the cylinder screws into in the regulator housing must be properly fitted and correctly tightened up, this is to prevent the cylinder rocking on it's threads disturbing the o ring which sits on the brass spigot the cylinder screws into, 90% of HW leaks are here, its a little O ring but by heck does it cause problems if it's not assembled correctly.

Back the hammer right off, set the reg to 90 bar (.177) or 85 for (.22) then dry fire the rifle adjusting the hammer in slightly each time until you get a solid bang from the muzzle, this ensures the pellet does not end up sitting in the barrel due to lack of air, then put it over the chrono, you should be able to set to 11.5ftlbs easily on the hammer and this will then be set to factory spec, you can mess about with reg pressure and hammer balance but that's for experienced guys, just use the factory spec.

If you strip the reg out clean all the belville washers wipe them with a little oil before assembling and stack like this (())(())(())(()) on a screwdriver or rod and then slip them in on the screwdriver so they all stay lined up.

Most important, keep everything clean, work on a cotton sheet or newspaper, dust and grit is the biggest enemy , clean it properly, it's amazing how many rifles get assembled dirty!

If power is increasing as the pressure drops this points to the reg being over pressure, the hammer can barely open the valve until the pressure drops, you really need to set this accurately with a reg tester, theres no real option , the HW100 is a very good rifle, but like all complex machines needs to be set up correctly, once you get it shooting get back to us and we can have a look at why you think the accuracy is wanting.

[GrahamHenderson]

For Sale, HW100, one careful owner from new, . . . . . .

It's now running at 8ft/lbs, and as you get down to 110bar its nearly over the legal limit?!?!?!

haha! classic power spike, turn your reg down a tad

clean and oil the hammer

DO NOT OIL THE HAMMER
the oil will cause drag, sounds silly but its true!

DON`T dissasemble the reg, you will only add more grief

[mikehill]

Will it really cost a few hundred quid to get someone to fix it ?

[Artfull-Bodger]

NO it just needs putting together properly, its a case of lots of enthusiasm but little experience, there's nothing here that can't be fixed easily , ONCE you know what's wrong.

[Rgrc29]

I've ordered the reg tester, some more seals, and likely a new set of belville washers.
The regulator is the only thing I've not dissambled and cleaned, I'll give this a go and then work my way back through.
I've investigated getting it tuned by a professional, and including postage most of them cost upwards of £150 - 250.

The hope is I can sort this myself and learn a bit about the system on the way.

[Rickyg]

defo spiked the reg..you need to get it back to factory spec.

is it .177? if so they can be super pellet fussy.

As you are not far from me, once you have gotten the reg back in line I can lend you another barrel to test accuracy and I have a shed load of different brands, weights etc from when I did my testing on my KTL. I did have a reg tester but lost it and no idea where its gone otherwise I could have done it all for you as I have tonnes of O-rings etc.

I thought mine was knackered and ordered a spare barrel...got the same results pretty much. I have two 100Ks and both prefer heavier pellets.

1: JSB heavy - Great pellet and a true tack driver.
2: H&N barracuda
3: Bisley Magnum (same pellet as above just not sorted as well)

JSB exacts...I might as well not bothered. So many wild flyers its untrue.

[UrbanFox]

defo spiked the reg..you need to get it back to factory spec.

is it .177? if so they can be super pellet fussy.

As you are not far from me, once you have gotten the reg back in line I can lend you another barrel to test accuracy and I have a shed load of different brands, weights etc from when I did my testing on my KTL. I did have a reg tester but lost it and no idea where its gone otherwise I could have done it all for you as I have tonnes of O-rings etc.

I thought mine was knackered and ordered a spare barrel...got the same results pretty much. I have two 100Ks and both prefer heavier pellets.

1: JSB heavy - Great pellet and a true tack driver.
2: H&N barracuda
3: Bisley Magnum (same pellet as above just not sorted as well)

JSB exacts...I might as well not bothered. So many wild flyers its untrue.

Sorry to butt in on this but did you find this using the mags or single pellet loader or both. Just interested.

atb

Bri

[Rickyg]

both, made no difference.