Tuning BRK Ghost .22 HP not producing power any suggestions?

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robertwalsh1981

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Jun 3, 2024
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I have been tinkering with my Ghost, swapped springs out for the White spring and then Blue spring, and testing different reg pressures and now it is only able to achieve ~620 FPS with the following configuration.

BRK Ghost .22 HP
23" barrel
Red Hammer Spring
Tank ~190 BAR
Reg ~165 BAR
PW Max
JSB Exact RS Diablo 13.43 gr.
FPS = 622 (highest)

When it first arrived it was cranking the JSB Hades 15.89 gr pellets at close to 1030 FPS with the following configuration:

BRK Ghost .22 HP
23" barrel
Red Hammer Spring
Tank ~190 BAR
Reg ~150 BAR
PW Min
JSB Exact RS Diablo 15.89 gr.
FPS = 1030

I am charging it from a Yong Heng compressor with this secondary water/oil separator in line between the compressor and the gun.


I should also mention that when degassing the gun it is taking 15+ shots with the PW on MAX setting before the reg pressure drops below 50 BAR, not sure if this is relevant, but from my limited experience/knowledge it seems to indicate that perhaps the valve is not opening fully?

Any thoughts or suggestions on what might cause this behavior?
 
Last edited:
Have you ever pulled the barrel?
If you put it back in with the transfer port "up" you'd certainly have a hard time making any power, even with a a 165bar reg pressure.

That's the first thing that comes to mind, transfer port is pointed the right direction to accept the full flow of air from the valve below.
 
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Franklink said:
Have you ever pulled the barrel?
If you put it back in with the transfer port "up" you'd certainly have a hard time making any power, even with a a 165bar reg pressure.

That's the first thing that comes to mind, transfer port is pointed the right direction to accept the full flow of air from the valve below.
Click to expand...
I have pulled the barrel, I thought that I made sure to put it back the way it came out, but... I will go verify my work. 😅

Thank you
 
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Definitely off. For reference, mine sends Hades at around 940-950 fps on PW Min (or 1, I forgot since it’s been a while that I shot super light pellets with it) at 142ish bar and with the blue spring.

Ideas:

- Pellet debris blocking hammer/spring
- Hammer damaged
- Barrel o ring (TP, probe). You should feel a blast when taking a shot though and I wouldn’t expect that to take this much speed
- valve locked mechanically somehow, debris or similar

Your best bet are frankling and zx10wall, they know the Plattform inside out.
 
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With a 23" .22 and 165 bar reg pressure you should be supersonic with 13.43gr pellets. Shouldn't need the reg anywhere near that high for that pellet.

Is there a way the springs could be mixed up? With a really light hammer spring, I wouldn't be surprised at some partial valve lock with a reg pressure of 165 bar.

I'm sorry I don't know the colors of the hammer springs. But the 0.047" wire diameter hammer spring, and a reg pressure down 100bar should be netting you much more reasonable speeds from that pellet...I'd estimate something like 850-950fps.
 
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Franklink said:
Or a missing probe oring (groove inside the barrel) maybe...
Click to expand...
The oring appears to be in place and I cannot see any apparent damage to it
20250120_114851.jpg


I just finished firing multiple shots and listening/feeling for any air leaks near the magazine, else ware and I am not finding anything. I suspect a field stripping of the hammer is in my near future.
 
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Franklink said:
@greenbeans suggestion of a smashed pellet (or pelletS) in the hammers raceway is a very good suggestion too.

They can fall backwards from the loading area and end up in front of the hammer.
Click to expand...
Didn’t realize you were already on it helping our fellow ghost shooter out, when I started typing the threat didn’t have any comments but then I got distracted :)

robertwalsh1981 said:
The oring appears to be in place and I cannot see any apparent damage to itView attachment 530943

I just finished firing multiple shots and listening/feeling for any air leaks near the magazine, else ware and I am not finding anything. I suspect a field stripping of the hammer is in my near future.
Click to expand...
Seems like you gotta take the hammer out indeed. Ghost is a pleasure to work on though, so not a big deal to take a look inside :)

Also just put the .22 HP barrel back on and shot a couple of different pellets to give you a reference (had a 28 inch .25 barrel on it):

142ish bar - as per my reading of the baby gauge
Blue spring
Hades: PW min 935fps
AEA 18gr: PW 6 980fps
AEA 22gr: PW 11 960fps
AEA 25gr: PW 16 950fps
 
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robertwalsh1981 said:
The oring appears to be in place and I cannot see any apparent damage to itView attachment 530943

I just finished firing multiple shots and listening/feeling for any air leaks near the magazine, else ware and I am not finding anything. I suspect a field stripping of the hammer is in my near future.
Click to expand...
Here is some examples of where you should be based on a collaborative data thread on the ghost:


.22 barrel (23inches, 5 groove polygonal, choked, 1:30)
Franklink (Cole)


28.55s @ 960fps on MAX

  • Extended pin probe
  • 545grain hammer (non-adjustable preload with this hammer)
  • 0.051” wire hammer spring
  • Regulator at 150 bar
  • Hammer spring tension on MAX


Ghost XR Carbine = As received from AOA. Spring used is unknown (assume white) ?

JSB Exact Jumbo 18.13 @
902 FPS avg.
900 min. / 905 max.
Spread 5
Standard deviation 2
Regulator @ 100 BAR / Power Wheel on 10



10/13/24 add:



23" .22 barrel. (Goal was testing of some 23grain .22 pellets).

Only change was the barrel.

To recap from my earlier post here....
18.9s at 910-915fps on MAX (35fpe)

  • Extended pin probe
  • 455grain hammer (skeletonized)
  • Preload adjustment about 1/8” proud of hammer body (threaded insert in nose of hammer on the earliest Ghosts)
  • 0.051” wire hammer spring
  • Regulator @ 122-124 bar


23grain .22s with all of the above, maxed out at 983fps (978-983 for 5 shots) (49fpe)
Cross section (0.20 versus 0.217) and a difference of about 5 inches worth of barrel.



From AOA YouTube:



23”barrel, .22 jsb, JSB 18 gr, white spring, reg at 140

Pwr wheel at min = 495 fps

Pwr wheel at medium 10 = 645 fps

Pwr wheel at max 20 = 760 fps



Switching to Yellow Spring, adjusting pwr wheel only:

23”barrel, .22 JSB 18 gr, yellow spring, reg at 140

Pwr wheel @ min = 870 fps

Pwr wheel @ 10 / med = 950 fps

Pwr wheel at max 20, = 980 fps



.22 Barrel @ 23” Multi-Pellet Weight(s) optimum balance tune w/o spring or reg change. This is a great one barrel multi pellet weight tune and maximizes air usage. NOTE: older springs/newer springs may vary FPS results in addition to 3-5 shots to settle when changing power wheel setting – remember to only adjust power wheel with breech closed.



White Spring, Regulator set to 115 Bar



Min PWR 15 Gr .22’s at 880



Med PWR 18 Gr at 880



Max PWR 25 Gr at 870



22 HP 23 inch barrel, reg 152ish (damn baby gauges…), blue spring:

AEA 25.3gr at 950fps on PW 16
AEA 21.9gr at 915fps on PW7
Hades 15.89gr at 940fps on MIN (they’re surprisingly accurate at that speed).

Could obviously shoot 18gr as well but the gun/barrel likes the 3 mentioned above so no need to try a 4th :)



My .22 Ghost Carbine as received from AOA:

JSB Exact Jumbo 18.13 @ 902 FPS avg.
900 min. / 905 max.
Spread 5
Standard deviation 2
Regulator @ 100 BAR / Power Wheel on 10



.25 barrel (23inches, 5 groove polygonal, choked, 1:17

23” Barrel, 145 bar, red spring, PWR Wheel 5, 33gr JSBs @ ( fps? ) reports sub moa group at 50 yards
 
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robertwalsh1981 said:
I have been tinkering with my Ghost, swapped springs out for the White spring and then Blue spring, and testing different reg pressures and now it is only able to achieve ~620 FPS with the following configuration.

BRK Ghost .22 HP
23" barrel
Red Hammer Spring
Tank ~190 BAR
Reg ~165 BAR
PW Max
JSB Exact RS Diablo 13.43 gr.
FPS = 622 (highest)

When it first arrived it was cranking the JSB Hades 15.89 gr pellets at close to 1030 FPS with the following configuration:

BRK Ghost .22 HP
23" barrel
Red Hammer Spring
Tank ~190 BAR
Reg ~150 BAR
PW Min
JSB Exact RS Diablo 15.89 gr.
FPS = 1030

I am charging it from a Yong Heng compressor with this secondary water/oil separator in line between the compressor and the gun.


I should also mention that when degassing the gun it is taking 15+ shots with the PW on MAX setting before the reg pressure drops below 50 BAR, not sure if this is relevant, but from my limited experience/knowledge it seems to indicate that perhaps the valve is not opening fully?

Any thoughts or suggestions on what might cause this behavior?
Click to expand...

Brocock/BRK - Ghost collaborative data request

I’m trying to create a cheat sheet for the FAC Ghosts when wanting to change calibers or barrel length and or pellets efficiently. I have ALL barrel(s) lengths and calibers, including a .20 available to me. I want to hear from folks who have found the perfect combination of: Regulator pressure...
www.airgunnation.com www.airgunnation.com
 
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Franklink said:
With a 23" .22 and 165 bar reg pressure you should be supersonic with 13.43gr pellets. Shouldn't need the reg anywhere near that high for that pellet.

Is there a way the springs could be mixed up? With a really light hammer spring, I wouldn't be surprised at some partial valve lock with a reg pressure of 165 bar.

I'm sorry I don't know the colors of the hammer springs. But the 0.047" wire diameter hammer spring, and a reg pressure down 100bar should be netting you much more reasonable speeds from that pellet...I'd estimate something like 850-950fps.
Click to expand...

Unfortunately I don't have a way to measure the hammer spring wire diameter, but per the documentation this is the color coding.
SmartSelect_20250109_154026_Gallery.jpg


I have taken apart the rear of the gun and the hammer assembly, there does not appear to be any damage or debris present.

The probe oring has been lubed, and I also tried changing out the springs to see if it makes any difference, below are my findings.

These settings were the same for all shots, only change was swapping out the springs.
Reg = 115 BAR
JSB Exact RS Diablo 13.43 gr.
PW=Max
11 shots

White spring:
Hi=482 fps
Low=471 fps
Ave=475 fps

Blue spring:
Hi=531
Low=522
Ave=529

Red spring (Factory):
Hi=550
Low=545
Ave=548

Red spring (Kit):
Hi=552
Low=543
Ave=548

Black spring:
Hi=568
Low=559
Ave=563

Green spring:
Hi=571
Low=557
Ave=563

Yellow spring:
Hi=587
Low=582
Ave=584


I then increased the reg to 140 BAR and reshot the Yellow and blue springs:
Reg = 140 BAR
JSB Exact RS Diablo 13.43 gr.
PW=Max
11 shots

Yellow:
Hi=652
Low=633
Ave=641

Blue:
Hi=594
Low=585
Ave=588

Not sure if it matters, but with the reg set to ~115 BAR wouldn't I expect to see the fps flatline at some point with the stronger springs as eventually all of the stronger springs should be opening the valve completely?

Out of time today to continue shooting, now for research to see what else I might look for. @greenbeans mentioned possibly "- valve locked mechanically somehow, debris or similar" if I end up needing to pull the valve I will have to order a valve tool or some snap ring pliers.

Any additional thoughts or suggestions are appreciated.
 
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cavedweller said:

Brocock/BRK - Ghost collaborative data request

I’m trying to create a cheat sheet for the FAC Ghosts when wanting to change calibers or barrel length and or pellets efficiently. I have ALL barrel(s) lengths and calibers, including a .20 available to me. I want to hear from folks who have found the perfect combination of: Regulator pressure...
www.airgunnation.com www.airgunnation.com
Click to expand...
Thank you, I follow that thread and it has been quite useful. I intend to contribute to it once I get this issue figured out and I can get some decent info for it.
 
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Struckat said:
Is the chrony working properly?
Click to expand...

Or the regulator gauge?

Is this a relatively new Ghost? Or did you pick it up used?
Where I'm going with that question is that early ones had a threaded extension in the nose of the hammer....if that's the case, and it worked its way loose, that would make it very hard to increase the fps, as your hammer "throw" would be minimized by the effectively longer hammer, and reducing the hammer strike on the valve.
 
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robertwalsh1981 said:
Unfortunately I don't have a way to measure the hammer spring wire diameter, but per the documentation this is the color coding.
View attachment 530987


Not sure if it matters, but with the reg set to ~115 BAR wouldn't I expect to see the fps flatline at some point with the stronger springs as eventually all of the stronger springs should be opening the valve completely?
Click to expand...


Yes, when you're at a relatively low reg pressure, in your example, 115 bar, you get to a point that hitting the valve harder doesn't increase the fps. That's because the low reg pressure is the power limiting factor.

But it sounds like you've swung through the reasonable reg pressures and still aren't getting the power you should be.

Head scratcher.
 
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robertwalsh1981 said:
Unfortunately I don't have a way to measure the hammer spring wire diameter, but per the documentation this is the color coding.
View attachment 530987

I have taken apart the rear of the gun and the hammer assembly, there does not appear to be any damage or debris present.

The probe oring has been lubed, and I also tried changing out the springs to see if it makes any difference, below are my findings.

These settings were the same for all shots, only change was swapping out the springs.
Reg = 115 BAR
JSB Exact RS Diablo 13.43 gr.
PW=Max
11 shots

White spring:
Hi=482 fps
Low=471 fps
Ave=475 fps

Blue spring:
Hi=531
Low=522
Ave=529

Red spring (Factory):
Hi=550
Low=545
Ave=548

Red spring (Kit):
Hi=552
Low=543
Ave=548

Black spring:
Hi=568
Low=559
Ave=563

Green spring:
Hi=571
Low=557
Ave=563

Yellow spring:
Hi=587
Low=582
Ave=584


I then increased the reg to 140 BAR and reshot the Yellow and blue springs:
Reg = 140 BAR
JSB Exact RS Diablo 13.43 gr.
PW=Max
11 shots

Yellow:
Hi=652
Low=633
Ave=641

Blue:
Hi=594
Low=585
Ave=588

Not sure if it matters, but with the reg set to ~115 BAR wouldn't I expect to see the fps flatline at some point with the stronger springs as eventually all of the stronger springs should be opening the valve completely?

Out of time today to continue shooting, now for research to see what else I might look for. @greenbeans mentioned possibly "- valve locked mechanically somehow, debris or similar" if I end up needing to pull the valve I will have to order a valve tool or some snap ring pliers.

Any additional thoughts or suggestions are appreciated.
Click to expand...
Yeah you would expect fps to flatline (almost) at some point at that pressure. But there isn’t too much of a difference between blue/red/yellow so the relation of speeds make sense to me.

That said, there seems to be something stopping your valve from fully opening and the stronger the spring the more it is opening. Did you check the hammer for “lost” pieces? I think to remember that someone had a damaged hammer (which would give you a lighter hammer - too light). If that isn’t it either you’ll have to pull the valve I guess. Ah and maybe check that the power wheel is properly aligned and not loose (there is a set screw in there, if it’s loose you may basically be shooting on min all the time).
 
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