The OTHER Marauder. Regulated .22 Initial Results

[triggertreat]

It sounds like you may have a velocity regulator in the barrel......

Lol, I would certainly have that MM barrel spotless and pellets lubed for best velocity.

[ackuric]

There has to be either a restricted air way somewhere (barrel regulator, haha) or a significant leak that only allows so much pressure to build behind pellet before leaking?

I would go as far as tossing the .25 cal's plenum onto the .22 cal to see if it makes any significant difference having a slightly larger plenum, as it should...but that is a lot of work that I would personally do just to be conclusive!

[Dairyboy]

It sounds like you may have a velocity regulator in the barrel......

Lol, I would certainly have that MM barrel spotless and pellets lubed for best velocity.

Lol is right! Yeah make sure it's clean and also remember these barrels are tight! You lose a good 20-30fps from these barrels over the stock ones.

[n2omike]

This is how it did BEFORE installing the regulator...
https://www.gatewaytoairguns.org/GTA/index.php?topic=122114.msg1185274#msg1185274

All I did besides adding the regulator, is changed to a 0.160" trasfer port and a 39.5 gram hammer.  That, and I didn't need the depinger and gauge block anymore.  Even at 2000 psi, it was still shooting 906 fps through a 0.122" Transfer Port.  Go Figure...

Gen II .22 Marauder
WAR Depinger
Opened up Gauge Block
Hill Valve
Stock 0.122" Transfer Port
WAR TSS
WAR MDS 60 gram Nylon/Brass Hammer
Marmot Malitia Hammer Forged Barrel
18.1 grain JSB pellets.  Tin of 500 lubed with 20 drops FP-10 oil

FIRST trial...  and ONLY one for tonight.  Just a run-down to make sure it works.  lol
3000 - 2000 psi (30 shots)

Middle screw of TSS backed ALL THE WAY OUT on lowest setting.

1.  942
2.  933
3.  942
4.  966
5.  946
6.  965
7.  944
8.  942
9.  944
10. 946
11. 946
12. 945
13. 951
14. 947
15. 944
16. 942
17. 942
18. 966
19. 938
20. 936
21. 933
22. 933
23. 928
24. 925
25. 922
26. 921
27. 936
28. 907
29. 910
30. 906

[n2omike]

Don't know why any of you genius individuals didn't recommend this, but here's what I did to rule out the regulator/plenum...

I REMOVED the regulator, and pumped the gun up to the regulator set point, and tried it at that pressure...  sans regulator.

According to the data in the previous post, it SHOULD have shot around 906 fps...  and it did that with a 0.122 TP.  With the 0.160" unit, an even heavier hammer, and MORE spring tension, it should have shot significantly faster than that! 

Guess what?

SAME FRIGGIN 830 FPS!!!!!!!

So, there's a major restriction SOMEWHERE.  I have a stock .22 and a stock .25 valve I could try, and see if that changes anything.  I took the Hill unit apart, and didn't see anything wrong.  The plunger seems work just fine.  I'm about at a friggin' loss.  At least I know it's NOT the regulator or plenum. 

I love this gun...   

[ackuric]

Don't know why any of you genius individuals didn't recommend this, but here's what I did to rule out the regulator/plenum...

I REMOVED the regulator, and pumped the gun up to the regulator set point, and tried it at that pressure...  sans regulator.

According to the data in the previous post, it SHOULD have shot around 906 fps...  and it did that with a 0.122 TP.  With the 0.160" unit, and even heavier hammer, it should have shot significantly faster than that, even. 

Guess what?

SAME FRIGGIN 830 FPS!!!!!!!

So, there's a major restriction SOMEWHERE.  I have a stock .22 and a stock .25 valve I could try, and see if that changes anything.  I took the Hill unit apart, and didn't see anything wrong.  The plunger seems work just fine.  I'm about at a friggin' loss.  At least I know it's NOT the regulator or plenum. 

I love this gun...   

I suggested exactly this...restriction or air loss/leak

[n2omike]

I suggested exactly this...restriction or air loss/leak

Yea, there has to be a restriction or leak SOMEWHERE.

I just got finished taking the gun COMPLETELY apart.  There's really nothing to that valve.  It opens just fine.  The TP is metal, and uses the gaskets.  Hard to have much of a leak there, I would think.  Barrel port is aligned just fine with the Transfer.  When the lighter valve spring comes in, I'll re-assemble the gun with exacting care and all new o-rings/gaskets/seals, making sure everything is aligned just right, and will give the barrel another scrub down...  and we'll see what happens.  I've got the barrel out...  everything completely apart.

Fun Stuff...  Can't blame the regulator guy.  The one in the .25 works superb, and I gave him free reign on how to set that one up.  Guy really seems to know his stuff.  Maybe I'll install another Transfer Port, just in case this one might be cracked or something.  I've got another 0.160" unit.  I'll put it in there, along with some new gaskets.  Either that, or use one of the poly units.  Hill makes a REALLY nice one out of good material.  They come cut super straight, and are the perfect length to crush just the perfect amount.  Best ones I've seen from anywhere.  They work great in the .25.  That will be my next move if the next re-assembly once the new valve spring comes in doesn't work out.

On the other hand...  I'm getting a LOT faster at tearing this thing down and putting it back together!  LOL

Thanks for all the insight!  I'll keep you guys posted!   

[triggertreat]

You mentioned a 39 gram hammer at one point and waiting on a lighter valve spring.   Just make sure you have plenty of hammer energy to open the valve enough.  You stated you ruled out the regulator so it's got to be something simple along those lines.  Not much else left unless the poppet is not opening enough or gauge is way off.

[Christopher]

n2omike,
Does your MDS hammer have little grooves on the sides of the hammer to allow air to go past the hammer in flight? If the hammer is a little snug as far as tolerances it could be experiencing some sort of an air lock. I've seen some hammer with the little grooves machined down the sides and I'v also seen hammers with holes drilled through them. If you got your TSS from Travis you'll probably have a hole through your endcap where the adjustment screws are, that is there so "air cushioning" isn't a problem. Bob had a build one time with similar symptoms and I think Gippeto suggested this as the problem, IIRC.

Chris

[n2omike]

n2omike,
Does your MDS hammer have little grooves on the sides of the hammer to allow air to go past the hammer in flight? If the hammer is a little snug as far as tolerances it could be experiencing some sort of an air lock. I've seen some hammer with the little grooves machined down the sides and I'v also seen hammers with holes drilled through them. If you got your TSS from Travis you'll probably have a hole through your endcap where the adjustment screws are, that is there so "air cushioning" isn't a problem. Bob had a build one time with similar symptoms and I think Gippeto suggested this as the problem, IIRC.

Chris

Yes, the hammers from David (Rocker1) that I have in the .25 and .22 both have grooves in the side.  Plus, I have tried another, heavy hammer in the gun as well.  No change.  I've got the gun torn completely apart (barrel removed, valve apart etc)  Once the lighter valve spring comes in the mail, I will do a very careful re-assembly with all new o-rings and TP gaskets.  If it still won't "open up" I'll try a poly TP...  and maybe grab the gun by the butt stock, and use it to try and chop down a tree!  lol

There SHOULD be something obvious...  but, I'm just not seeing it.

Thanks, guys.

[ackuric]

n2omike,
Does your MDS hammer have little grooves on the sides of the hammer to allow air to go past the hammer in flight? If the hammer is a little snug as far as tolerances it could be experiencing some sort of an air lock. I've seen some hammer with the little grooves machined down the sides and I'v also seen hammers with holes drilled through them. If you got your TSS from Travis you'll probably have a hole through your endcap where the adjustment screws are, that is there so "air cushioning" isn't a problem. Bob had a build one time with similar symptoms and I think Gippeto suggested this as the problem, IIRC.

Chris

Yes, the hammers from David (Rocker1) that I have in the .25 and .22 both have grooves in the side.  Plus, I have tried another, heavy hammer in the gun as well.  No change.  I've got the gun torn completely apart (barrel removed, valve apart etc)  Once the lighter valve spring comes in the mail, I will do a very careful re-assembly with all new o-rings and TP gaskets.  If it still won't "open up" I'll try a poly TP...  and maybe grab the gun by the butt stock, and use it to try and chop down a tree!  lol

There SHOULD be something obvious...  but, I'm just not seeing it.

Thanks, guys.

Did you ever hear back from Lane on the plenum threads for the gauge? He was fairly dismissive when I inquired about it and refused to accept something was wrong with the threading.

[n2omike]

Did you ever hear back from Lane on the plenum threads for the gauge? He was fairly dismissive when I inquired about it and refused to accept something was wrong with the threading.

We exchanged about 25 emails.  I believe he realizes it, but he mentioned having about 100 plenums already CNC machined...  and I don't think he wants to throw in the trash.  lol

[ackuric]

Did you ever hear back from Lane on the plenum threads for the gauge? He was fairly dismissive when I inquired about it and refused to accept something was wrong with the threading.

We exchanged about 25 emails.  I believe he realizes it, but he mentioned having about 100 plenums already CNC machined...  and I don't think he wants to throw in the trash.  lol

Right on, I am not concerned as mine is leak free and I can achieve a seal.

[makoda]

did you double check the velocity port screw on the side of the gun to make sure it was still fully open?  sometimes when tightening the set screw it will screw in the other one as well.

[triggertreat]

did you double check the velocity port screw on the side of the gun to make sure it was still fully open?  sometimes when tightening the set screw it will screw in the other one as well.

In the OP he mentioned a Hill valve which does not have a VMS.

[n2omike]

The parts from Hill Air Guns came in today.  Got the 6lb valve spring, new gaskets, o-rings, even a new 0.162" transfer port!
Was careful, and put it all back together very carefully...   Even turned the regulator back down to 130 Barr.
Tested...
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810 fps.  This was with it turned all the way down...  so I turned up the compression of the inner spring of the TSS all the way up, and guess what!  NO CHANGE!!!!!   
LOTS of $(Q&*^$)#$*%^)$)%~@# ensued!!!!
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Didn't really like the transfer port arrangement for some reason, and decided to install one of the Hill 0.0187" poly units.  With it turned all the way down again, 900 fps!!!!         

I don't know WHAT the problem was with those other Transfer Ports, but will probably look at them, take some measurements, and compare the Hill 0.162" units to the stock ones, and see if there are any differences.  (gun without the regulator was shot with a stock 0.122" TP) 

But, first....   I'll load up some pellets, air up the gun, and do a shot string.   

To be continued!

[n2omike]

Okay, first shot string...  Starting at 3100 psi, down to about 1400 psi.  40 shots, and about 30-34 good ones...   or 3 mags. 
I'm not sure what velocity these Marmot Militia Hammer Forged barrels like with the 18.1 grain JSB pellets, but last I read, I think it was about 875-880.  Seems like it needs slowed down just a tad, and may be a little bit of an air hog.  May have to re-install the 28 lb valve spring.  lol  Might save a little air, and knock the velocity down just a tad.  Right now, I'm just glad it's finally working...  and I wasn't forced to try to take it by the butt stock, and attempt to chop a tree down with it!   

1.  907
2.  895
3.  896
4.  898
5.  894
6.  895
7.  902
8.  891
9.  901
10. 893

11. 904
12. 897
13. 898
14. 903
15. 892
16. 899
17. 903
18. 892
19. 902
20. 896

21. 895
22. 892
23. 901
24. 894
25. 890
26. 903
27. 890
28. 894
29. 887
30. 897

31. 888
32. 880
33. 879
34. 878
35. 847
36. 860
37. 865
38. 844
39. 839
40. 825

[triggertreat]

Now you're cooking with gas.  What was the ending pressure?  Looks like to me if you just backed off on the hammer you could level out the declining string.  It may take a little more tweaking but that would be a good start IMO.  The MM barrel does well around 850-890 for me.

[n2omike]

Now you're cooking with gas.  What was the ending pressure?  Looks like to me if you just backed off on the hammer you could level out the declining string.  It may take a little more tweaking but that would be a good start IMO.  The MM barrel does well around 850-890 for me.

I already pulled it back apart, and installed the 28lb valve spring.  I'll put it back together, and see what that one change does.  After that, we'll see about backing the hammer spring off. 

I did take some measurements of the Transfer Ports.  The Hill 0.162" has an OD of 0.192" where it fits inside the gaskets.  The stock valve measures 0.178".  This makes it really hard to install.  I can install one gasket on the TP, and use a flat screwdriver to squeeze the assembly down into the pressure tube, then stretch the second gasket on the TP...  and lower the receiver down onto it.  It SEEMS to go on fine, but I believe things go awry, and the gasket slips off.  Upon disassembly, there is a line on the gasket where it looks like the sharp end edges are just pressing on the end of the gasket, instead of being inserted into it.  Pressure hits it, and it leaks.  Hill's poly unit is cut to the perfect length, is the perfect material, and is dead straight on both ends.  Easy, peezy! 

Oh well, time to go put this thing back together for the 100th time!  lol

[pcp_Dave]

I'm glad you found it. I have been following this with great interest. maybe the seal was partially covering the port or leaking as you said. Either way it's wonderful that you're back up to power. I really want to do some work on mine just can't seem to get started.
Best.