So, I'm having a couple issues trying to up my reg pressure. I would like to increase the pressure to gain some efficiency and decrease the noise. Twice, I've turned the nut 1/4 turn CW while holding the inner hex key stationary. The reg pressure hasn't changed. It's stuck at around 90bar. (I'd like to be closer to 115 - 120 Bar.) Also, when I pull the bottle, the reg is dumping its air too. Is there a seal that's bad in the reg?
The reg was previously at about 90 - 100 Bar, based on shooting over a Chrony and watching the speed drop. Each time I adjusted the reg, I filled the gun up to 120 bar and shot it until I saw a consistent drop in speed. The first 2 times I turned the nut 1/2 turn CW (while holding the inner hex hey still and not turning the stack) and saw a drop in speed at the same point - at about 90 - 100 Bar. I just tightened the reg nut another 1/2 turn CW, and still didn't see a change. This means that I've gone a full turn CW on that nut WITH NO CHANGE??? My understanding is that the RAW regulator increases the output pressure by 5 - 10 bar with each 1/4 turn clockwise. Something is definitely wrong???
Any guidance would be greatly appreciated.
Thanks!
Change the washer stack to (()) and so on
Quote from: Dave74 on November 05, 2022, 12:23:03 AM
Change the washer stack to (()) and so on
That's how it's set up now.
Mine was originally a sub 12 and at 40 bar it's now on ticket and set at150 bar .
Fairly sure mine is ((()))(((
Unless it has the MFR type reg the gun will dump the air, it doesn't necessarily mean that the reg is leaking. Some regs hold air for a few minutes .some dont.
If its dumping air now that you have adjusted the reg- as you tighten the stack core travel is reduced.
I guess that there's a faint possibility the nose contact is lighter.
I wouldn't trust either dive cylinder or QF gauge to be that accurate, I checked my cylinder against the large dial reg-tester and a digital gauge edit it was reading under so my fills were + 7bar.
If you're not using one screwed directly into the bottom of the block perhaps a more accurate gauge is in order instead of trial and error?
Could be a light seal on the valve face, if it's relatively noisy ( or has been getting noisier with more air use) perhaps its the exhaust valve? Stem o-ring? A 10p part failure.
Shouldn't be any need to go above 90-95bar with a sub-12 177, my Rapid runs quietly and efficiently at 95....same 480cc bottle gives 500 shots at 230bar.
That's with a 19" barrel and the shortest hammer spring I can get away with.
120bar seems a bit excessive, factory Rapids were set high 1700psi/117bar but as Kev will tell you 1350psi/93bar is his optimal pressure.
I started at 85, it was noisy- thrashing the reg with a low shot count.
The extra block volume of the 1000X should negate that issue.
Aggy would be able to tell you how he progressed with his conversion but iirc he was getting mid-30s from sub-12 spec at 130 bar?
have you seen how it behaves on ta reg tester its not just about the set pressure. when they say it should respond a certain way by each 1/4 of a turn is a load of rubbish as each reg can be different.
KevG
you may need a couple of extra bellevile washers on it.i always set the .177 to 1500 psi on the theobens and hm1000 but 1600 psi on the TM1000.
KevG
I'm sorry guys, I didn't quite give you enough info. This is a RAW HM1000X. I'm trying to tune it to shoot at 19.5fpe. Unfortunately, there isn't a reg tester available for the HMX series regs. I tried to find one but couldn't. I can't even find a way to attach a gauge to the bottom blanking plug. :-\
You guys have given me some great ideas of things to check - THANK YOU!
If the bottom blanking plug is still 1/4BSP it should be easy enough to get an adapter, believe HUMA sell digital gauges to suit if you can't find sepatates.
Ah...FAC, always help to have all the info.
1/4" bspp to 1/8" bspp adapter... Hose and gauge
(https://photos.imageevent.com/scl_electronics/gun/air/websize/guage.jpg)
screws into the bottom blanking plug.....
Stuart
I use a Parker service pro digital, not cheap but very good
Quote from: Ca_Varminter on November 05, 2022, 05:15:31 PM
1/4" bspp to 1/8" bspp adapter... Hose and gauge
(https://photos.imageevent.com/scl_electronics/gun/air/websize/guage.jpg)
screws into the bottom blanking plug.....
Stuart
Stuart, is the bottom blanking plug on the current RAW HMX rifles 1/4" bspp?
Also, I emailed HUMA about their gauge, but they couldn't confirm if it fit current production rifles.
Thanks again for all the info!
I believe so....
I don't own one ...
Raw list a 1/4"bspp plug on their site fore Rapids and Raw guns.....
Maybe someone who actually own one will chime In..
Or maybe KevG, he may have worked on one or two......
Stuart
They are the same as rapids , the same thread as the air cylinder , yes it does screw in
I found and ordered these parts - thank you so much for the help!!! What size o-ring do I need for the 1/4" BSPP connection to seal it against the block?
You don't use an O-ring here...
A Dowty sealing washer!!
(https://photos.imageevent.com/scl_electronics/gun/air/1_4%20bspp%20qf.jpg)
Stuart
Quote from: Ca_Varminter on November 07, 2022, 06:32:37 PM
You don't use an O-ring here...
A Dowty sealing washer!!
(https://photos.imageevent.com/scl_electronics/gun/air/1_4%20bspp%20qf.jpg)
Stuart
Ok thanks! Ummm what size do I need?
1/4" BSP..
Stuart
One last question on this - what size o-ring fits on the bottom blanking plug, in case I need to replace it?
If the bottom blanking plug I ring is crushed, leave it there and use the Dowty washer from the adaptor.
All of mine from the Theoben has been a Dowty washer.....
The only one I have seen that use an O-ring is Dr Bob's slimline blanking plug!!!
(https://photos.imageevent.com/scl_electronics/misc/drbob/websize/S%20line%20plug%201.jpg)
Stuart
Thanks!
The bottom blanking plugs I bought from raw in the theoben spare parts section has Orings not dowty washers, they have a groove machined on the flat part with an oring
I found an old post that states that it's normal for the plenum to degas if the pressure is lower than the reg set point. Is this true?
Thanks!
Yes....
It is called...Falling off the Reg....
Since there isn't enough pressure to close the Reg..
It will Free Flow...
Stuart
Quote from: Ca_Varminter on November 12, 2022, 05:22:55 PM
Yes....
It is called...Falling off the Reg....
Since there isn't enough pressure to close the Reg..
It will Free Flow...
Stuart
Thanks for the confirmation Stuart!
Just as follow up, I bought the HUMA gauge that is supposed to work with the RAW HM1000X rifles. Unfortunately, this gauge doesn't work. The tip of the threaded end hits the reg before it can screw in all the way. It only screws in as far as the red line shown in the picture.
I had to spin my adapter down in the lathe so that didn't happen
Quote from: Ca_Varminter on November 05, 2022, 05:15:31 PM
1/4" bspp to 1/8" bspp adapter... Hose and gauge
(https://photos.imageevent.com/scl_electronics/gun/air/websize/guage.jpg)
screws into the bottom blanking plug.....
Stuart
From my earlier post.....
That is why I went the hose route....
The 1/4" bspp fitting doesn't protrude that far into the receiver to interfere with the Reg.
Stuart
thats the way I usebto do them Stuart before I made a reg adapter tester.actualy its a good way of seing how the reg is ballance to the regulator
KevG