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Issue with RAW Reg

Started by Zack, November 04, 2022, 11:37:30 PM

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Zack

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!

Dave74

Change the washer stack to (()) and so on
Fit like n !!!

Zack

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.

Aggy

Mine was originally a sub 12 and at 40 bar it's now on ticket and set at150 bar .
Fairly sure mine is ((()))(((
Raw HM1000x fac .22
Skout Epoch .25 fac
Beretta 680

Ruger m77 mk2 .223
Many many many others been and gone

Squinty

#4
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?

KevG

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
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Regards KevG.
Administrator

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
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Regards KevG.
Administrator

Zack

#7
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!

Squinty

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.

Ca_Varminter

1/4" bspp to 1/8" bspp adapter... Hose and gauge

screws into the bottom blanking plug.....

Stuart
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Aggy

I use a Parker service pro digital, not cheap but very good
Raw HM1000x fac .22
Skout Epoch .25 fac
Beretta 680

Ruger m77 mk2 .223
Many many many others been and gone

Zack

#11
Quote from: Ca_Varminter on November 05, 2022, 05:15:31 PM
1/4" bspp to 1/8" bspp adapter... Hose and gauge

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!

Ca_Varminter

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

Aggy

They are the same as rapids , the same thread as the air cylinder , yes it does screw in
Like Like x 1 View List
Raw HM1000x fac .22
Skout Epoch .25 fac
Beretta 680

Ruger m77 mk2 .223
Many many many others been and gone

Zack

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?

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