GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Jacob_M on April 09, 2020, 03:14:16 AM
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Today I got back out there and put my .25 Raptor through another shot string with new found settings. This has been the best shot string so far and even confirmed the tuning method with another member and it worked for him as well.
Here is the string:
Start : 3700 PSI
End : 2000 PSI
Reg Set Point : 2000-1950 (Somewhere inbetween there)
Pellet : JSB King Heavies 33.95gr
885
891
887
891
879
891
880
886
890
888
883
886
883
884
886
888
881
885
888
893
874
885
878
880
891
887
880
886
895
883
894
894
886
893
894
885
887
882
878
880
890
877
880
883
874
885
878
878
887
880
885
878
883
877
878
884
872
874
There was also 5 shots on the same fill with 28gr AVS slugs, I wanted to test the FPS with ammo that was more precise weight wise.
955, 954, 953, 951, 954.
Total of 63 Shots.
Stats for 58 shots of JSB's 34gr.
Hi : 895
Lo : 872
Avg: 884
ES : 23
SD : 5
According to the Efficiency Calc. = 1.18 avg FPE/cuin per shot. ( this is assuming the Raptors plenum is 90cc) (I think this was correct.)
Anyways I am very happy with this tune right now. Here is how I got it.
TUNING METHOD
Since this valve is SUPER easy to open, you will find your optimal adjustments in a very small tuning window. Make sure to use very small adjustments at a time. We are talking 1/8 turns of the allen key.
Set Hammer Adjuster where it is recessed into the adjustment range. 2 or 3 threads should be visible.
Turn Hammer Buffer CCW until the gun does not fire.
Increase Hammer buffer 1/8 Turn at a time and fire the gun through chrony.
As you are doing this you will find your gun hits a max fps and if you continue to turn the buffer your velocity will begin to fall. Once Velocity falls turn your buffer back to your max FPS setting.
Now turn your hammer spring adjustment in CW, you will find your velocity increase to a point and then it will begin to decrease. Now turn the adjuster back to your max FPS setting.
Check your hammer buffer settings again now that you have a new hammer spring setting. Use TINY adjustments CW or CCW and just double check your buffer setting is still optimal.
Shoot over the chrony and see if you are hitting your desired FPS. If not, adjust regulator up or down until you hit desired power level.
I have not tested if changing regulator pressure requires you to re-adjust hammer and buffer settings. I'm ASSUMING that if anything needs to change, it should only be TINY adjustments.
ADJUSTABLE REGULATOR
I don't know if this will be the same for everyones Raptor, but for mine I feel my gun is MOST consistent when I fill to only 3600-3700psi. Any higher than this and my Extreme spread widens.
The reason for this is my regulator pressure will actually be 100 psi HIGHER when my bottle pressure is 4350-3900 psi. My first 10-15 shots will have higher velocities. Once my bottle pressure reaches
3600 psi or so, my reg pressure reads what I set it to. From 3600-3700 psi down all the way to 2000 psi my gun maintains a nice extreme spread for my uses.
I am still very happy that I can use 1700 psi worth of air and get 65 shots at 58-60fpe.
If I ever increase my regulator pressure to 2500psi + again I will revisit the idea of filling to 4350 psi.
There is not very many people putting out info on the Raptor even though there are so many out there. I hope this guide helps those who are trying to get theirs dialed in still.
Tuning the Raptor is unlike any gun I've tuned before. Big Learning curve and not for someone wanting a turn-key rifle. But if you enjoy the tuning process this gun will put your skills to the test lol. NOT for beginner pcp owners.
Raptor Saga Continues!
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If that regulator is creeping 100 PSI at 4350 PSI then I'll bet it is still creeping at 3700 PSI and under.
Here is what JSAR Nighthawk .30 got at the same reg pressure with 4500 psi fill:
https://www.gatewaytoairguns.org/GTA/index.php?topic=153807.msg155704345#msg155704345 (https://www.gatewaytoairguns.org/GTA/index.php?topic=153807.msg155704345#msg155704345)
Created: 02/06/19 02:15 PM
Description: JSAR Nighthawk.30
Notes 1: 4500-2000
Notes 2:
Distance to Chrono(FT): 1.00
Ballistic Coefficient: 1.000
Bullet Weight(gr): 50.00
Temp: 43 °F
BP: 30.23 inHg
Altitude: 0.00
# FPS FT-LBS PF
81 803 71.60 40.15
80 808 72.50 40.40
79 811 73.03 40.55
78 810 72.85 40.50
77 812 73.21 40.60
76 812 73.21 40.60
75 813 73.40 40.65
74 811 73.03 40.55
73 813 73.40 40.65
72 811 73.03 40.55
71 809 72.67 40.45
70 808 72.50 40.40
69 811 73.03 40.55
68 810 72.85 40.50
67 813 73.40 40.65
66 807 72.32 40.35
65 811 73.03 40.55
64 811 73.03 40.55
63 811 73.03 40.55
62 811 73.03 40.55
61 812 73.21 40.60
60 813 73.40 40.65
59 811 73.03 40.55
58 813 73.40 40.65
57 811 73.03 40.55
56 812 73.21 40.60
55 812 73.21 40.60
54 810 72.85 40.50
53 811 73.03 40.55
52 809 72.67 40.45
51 813 73.40 40.65
50 812 73.21 40.60
49 813 73.40 40.65
48 811 73.03 40.55
47 813 73.40 40.65
46 812 73.21 40.60
45 812 73.21 40.60
44 812 73.21 40.60
43 811 73.03 40.55
42 811 73.03 40.55
41 811 73.03 40.55
40 811 73.03 40.55
39 811 73.03 40.55
38 808 72.50 40.40
37 810 72.85 40.50
36 808 72.50 40.40
35 807 72.32 40.35
34 810 72.85 40.50
33 810 72.85 40.50
32 809 72.67 40.45
31 806 72.14 40.30
30 810 72.85 40.50
29 809 72.67 40.45
28 813 73.40 40.65
27 810 72.85 40.50
26 812 73.21 40.60
25 810 72.85 40.50
24 813 73.40 40.65
23 811 73.03 40.55
22 811 73.03 40.55
21 809 72.67 40.45
20 808 72.50 40.40
19 809 72.67 40.45
18 810 72.85 40.50
17 809 72.67 40.45
16 812 73.21 40.60
15 807 72.32 40.35
14 807 72.32 40.35
13 808 72.50 40.40
12 810 72.85 40.50
11 813 73.40 40.65
10 810 72.85 40.50
9 808 72.50 40.40
8 811 73.03 40.55
7 809 72.67 40.45
6 812 73.21 40.60
5 812 73.21 40.60
4 812 73.21 40.60
3 810 72.85 40.50
2 814 73.58 40.70
1 815 73.76 40.75
Average: 810.6 FPS
SD: 2.0 FPS
Min: 803 FPS
Max: 815 FPS
Spread: 12 FPS
Shot/sec: 0.0
True MV: 811 FPS
Group Size (in): 0.00
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( this is assuming the Raptors plenum is 90cc) (I think this was correct.)
I noticed the Raptor HP says it has a titanium plenum.
Does anyone know what the volume of that is?
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I noticed the Raptor HP says it has a titanium plenum.
Does anyone know what the volume of that is?
My HP .257 Raptor came with a Chrome Molly plenum, not Titanium.
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Thank you Jacob! This sounds pretty close to what I ended up doing with mine, but I'm going to try it again following these steps to see if I can get any improvements. Do you know if the Plenum on the Mini is the same as the regular Raptor, or is it smaller? I'll also have to check mine to see if the regulator fluctuates with tank pressure. Thanks for the heads up on that!
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During the course of my shooting I closely monitor my reg pressure. Once I get to 3700-3500psi the amount of creep is not noticeable if there is any.
I am able to verify this by getting a nice consistent string all the way down to my
2000psi set point.
Now that I’m thinking about it, the benefit to not filling to max pressure will save me some wear and tear on my compressor and adjustable regulator.
Paul,
The plenum on the mini is smaller. If I remember correct someone said it was 60cc. That’s my best guess, I think think the info for that # was in the jsar gate.
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The plenum on the mini is smaller. If I remember correct someone said it was 60cc. That’s my best guess, I think think the info for that # was in the jsar gate.
Which, unfortunately, is now gone! Oh well, there was a lot of good info there, maybe it will come back one day. Anyhoo, that for clearing that up! I'm looking forward to following your steps to see if I get an improvement over what I already have. You make a good point on the fill pressure to, since UPS seems incapable of delivering a compressor without destroying it, I'm stuck using my little Spark, and it really struggles doing a full 300 BAR fill!
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The plenum on the mini is smaller. If I remember correct someone said it was 60cc. That’s my best guess, I think think the info for that # was in the jsar gate.
Which, unfortunately, is now gone! Oh well, there was a lot of good info there, maybe it will come back one day. Anyhoo, that for clearing that up! I'm looking forward to following your steps to see if I get an improvement over what I already have. You make a good point on the fill pressure to, since UPS seems incapable of delivering a compressor without destroying it, I'm stuck using my little Spark, and it really struggles doing a full 300 BAR fill!
There is a OPEN vendor area for all vendors now and for the forseable future but that doesnt stop you from starting a tuning thread in the vendor area to expand apon.
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The plenum on the mini is smaller. If I remember correct someone said it was 60cc. That’s my best guess, I think think the info for that # was in the jsar gate.
Which, unfortunately, is now gone! Oh well, there was a lot of good info there, maybe it will come back one day. Anyhoo, that for clearing that up! I'm looking forward to following your steps to see if I get an improvement over what I already have. You make a good point on the fill pressure to, since UPS seems incapable of delivering a compressor without destroying it, I'm stuck using my little Spark, and it really struggles doing a full 300 BAR fill!
There is a OPEN vendor area for all vendors now and for the forseable future but that doesnt stop you from starting a tuning thread in the vendor area to expand apon.
I was referring to the old JSAR Gate that had a ton of information on a variety of products... Any chance of bringing that back and putting it in the Vendor area? It was just much more convenient to have one place to search instead of the entire forum.
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That's true as there was a LOT of info I wish I could look back on....Oh well the powers that be say no
Robert
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ADJUSTABLE REGULATOR
I don't know if this will be the same for everyones Raptor, but for mine I feel my gun is MOST consistent when I fill to only 3600-3700psi. Any higher than this and my Extreme spread widens.
The reason for this is my regulator pressure will actually be 100 psi HIGHER when my bottle pressure is 4350-3900 psi. My first 10-15 shots will have higher velocities. Once my bottle pressure reaches 3600 psi or so, my reg pressure reads what I set it to. From 3600-3700 psi down all the way to 2000 psi my gun maintains a nice extreme spread for my uses.
How much time do you take between each shot?
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For this shot string I waited about 5 seconds in between shots. There were a couple of 1-5 minute breaks in the shooting. After those breaks my velocity was still consistent.
The tune that I posted a couple weeks ago, I had a declining shot string. I did the same and waited 5 seconds in-between shots. At that time my hammer and buffer settings were not optimal and I was over dwelling the valve.
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The tune that I posted a couple weeks ago, I had a declining shot string. I did the same and waited 5 seconds in-between shots. At that time my hammer and buffer settings were not optimal and I was over dwelling the valve.
Looking at the data in the opening post of this thread...
The last group you shot (the 13 shot one) had the most velocities (Seven) in the 870s range + the lowest velocity overall as well at 872. This followed by the second to last group (which had 3 in the 870 range with a low of 874). The 2nd group you shot ( had only 2 velocities in the 870s). The first group you shot had the lowest number of velocity in the 870s range (only one) and it was 879.
Also notice the last group you shot (the 13 shot group) has no velocities in the 890's (highest is 887) whereas the other 3 groups that preceded it each have at least three velocities in the 890s.
Here is what I think might be happening:
https://hardairmagazine.com/ham-columns/tuning-regulated-pcp-airguns/
(https://hardairmagazine.com/wp-content/uploads/2019/03/HAM-3-Regulated-Tunes.jpg)
Note that even above the setpoint the velocity does not tend to be absolutely flat. This is because most regulators have some “creep”, ie the output pressure is slightly higher when the bottle/HP reservoir is full than when it is just above the setpoint pressure.
This difference is probably only 50-100 psi, but if you are tuning regulated PCP airguns on the plateau (blue curve), it may be enough that you see the velocity falling slightly even though you are well above the setpoint.
Conversely, if you are tuned on the downslope (10% or more below the plateau velocity – the grey curve), as the bottle pressure falls, and the output pressure creeps downwards, the velocity increases slightly.
Then when you hit the setpoint, and the regulator stops regulating, the output pressure starts to drop more rapidly. Then the velocity INCREASES, developing a bell-curve, just like an unregulated PCP. (Because below the setpoint, it is unregulated).
At somewhere around 3% below the plateau velocity (the red line – note all these percentages are just an estimate), the gun is operating near the peak pressure of what would be the bell curve at that hammer strike. This makes the velocity very stable over a wide range of pressures, and you should see no trend either up or down to the velocity above the setpoint.
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All of these shots are within a perfectly acceptable Extreme spread. All pellets were also pulled from the tin, no sorting involved.
I haven't seen that graph before. That does make perfect sense for my previous tune.
For my current tune I might be right on or right below the plateau. + or - 1%. The difference might be a 1/8 turn in the buffer or hammer adjustment.
What I have noticed with the balanced valve is getting below the plateau by 3 to 5% introduces more variance shot to shot.
Unless there is something else I am missing with the Raptor tune.
The report of my shot does sound more efficient. Much better than it was a week ago. Pretty quiet for 58-60fpe.
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Jacob, you are doing a GREAT job in posting your raptor tuning method. It will save use a lot of time and pellets for us Northerners that live in cold climates.
Right now it is too Rainy and cold to enjoy any outdoor tuning. Thanks for your reporting.
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Bob it's colder than average here too, we're even getting a little snow in parts but nothing that'll stick and it's windy too. I might do some chrony work today.
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Bob it's colder than average here too, we're even getting a little snow in parts but nothing that'll stick and it's windy too. I might do some chrony work today.
Wayne, most of this week it has been 35-40 degrees and raining, not my type of tuning/shooting weather.
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Bob it's colder than average here too, we're even getting a little snow in parts but nothing that'll stick and it's windy too. I might do some chrony work today.
Wayne, most of this week it has been 35-40 degrees and raining, not my type of tuning/shooting weather.
Got to love this New England weather. Or not. :'(
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I haven't seen that graph before. That does make perfect sense for my previous tune.
For my current tune I might be right on or right below the plateau. + or - 1%. The difference might be a 1/8 turn in the buffer or hammer adjustment.
What I have noticed with the balanced valve is getting below the plateau by 3 to 5% introduces more variance shot to shot.
Unless there is something else I am missing with the Raptor tune.
The report of my shot does sound more efficient. Much better than it was a week ago. Pretty quiet for 58-60fpe.
If you are right on the plateau then there is more room to reduce hammer spring. You want to get from the blue line to the red line on the chart.
If reducing hammer spring just a little bit results in more shot to shot variance then I would decrease reg pressure a little bit as the next step.
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Does anyone know the twist rate of the TJ's barrel liner in this .25 Raptor?
How about the maximum length projectile the magazine could hold?
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I will try and reduce hammer spring a little bit. A 1/4 turn will make a difference. Then I would need to run a shot string to see what’s going on.
The barrel is a 1:22 Twist TJ barrel.
Update on slug shooting:
Tried some 38gr AVS slugs, they were only going 850fps, but the first 3 shots went into the same hole at 30 yards!
Next 2 shots were about a half inch higher.
That is a first for this gun!
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isn't the length 3/4 of an inch?
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The barrel is a 1:22 Twist TJ barrel.
Update on slug shooting:
Tried some 38gr AVS slugs, they were only going 850fps
Do you know the groove diameter on the TJ's barrel?
The reason I am asking is because the AVS .25 slugs are sized .254" rather than .250" like the Neilsen slugs.
P.S. 850 FPS is a good velocity for a 38 grain slug (60 FPE).
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Messing with my tune again, just for the *(&^ of it.
Filled to 3500 psi.
Reg pressure at this fill is about 2250-2200. Max FPS with 34gr jsb is 934fps.
turned my buffer 1/8 turn and now my max FPS is 896.
Very consistent velocities from 3500-2700. Lots of 885-895 fps.
After 2700psi it was mostly 880-888 and gradually decreased till I got 874-880.
So, from this data, I believe that I CAN fill higher, maybe to 4000? or 4350 and see if my velocities start in the 880's and work its way up to the 890's.
Kind of feels weird that I have to follow the bell curve of my regulators set point.
Learning to get along with creep!
Filling higher I can probably get 70-80 shots at 57-60 fpe. If all shots stay within 875-895 fps I guess that is only a 20 Extreme spread.
Has anyone else had to do this with ANY other guns?
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Filled to 3500 psi.
Reg pressure at this fill is about 2250-2200. Max FPS with 34gr jsb is 934fps.
turned my buffer 1/8 turn and now my max FPS is 896.
Very consistent velocities from 3500-2700. Lots of 885-895 fps.
After 2700psi it was mostly 880-888 and gradually decreased till I got 874-880.
Sounds like you are still on the back side of the hammer spring bell curve. (reason: velocity is still dropping as bottle pressure decreases).
I suppose you have two choices at this point (from a purely reg pressure and existing hammer spring standpoint).
1. Decrease hammer spring once again. (with some risk of increasing shot to shot variance)
2. Keep hammer spring the same and increase reg pressure. (Could also risk increasing shot to shot variance if reg pressure is increased too much...this first starts occurring when bottle is at high pressure.)
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I’m going to increase my reg. Just a little bit and see what happens.
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The barrel is a 1:22 Twist TJ barrel.
According to the Kolbe twist calculator you could use any of the AVS .25 slugs (which as previously discussed are sized .254".)
(https://i2.wp.com/avsslugs.com/wp-content/uploads/2019/12/25-cal-AVS-sizes-DISH-scaled.jpg?fit=2560%2C933&ssl=1)
Up to 48 grain also works well with the plenum size of 90cc.
(Not sure how the stock transfer port factors in.... but at least those other two specs (rifling twist rate and plenum size) dovetail nicely)
P.S. For the 48 grain I calculate a sectional density of .106......so slightly below 2000 PSI would be the minimum pressure needed under ideal conditions for 950 FPS in a 24" barrel.
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The barrel is a 1:22 Twist TJ barrel.
According to the Kolbe twist calculator you could use any of the AVS .25 slugs (which as previously discussed are sized .254".)
(https://i2.wp.com/avsslugs.com/wp-content/uploads/2019/12/25-cal-AVS-sizes-DISH-scaled.jpg?fit=2560%2C933&ssl=1)
Up to 48 grain also works well with the plenum size of 90cc.
(Not sure how the stock transfer port factors in.... but at least those other two specs (rifling twist rate and plenum size) dovetail nicely)
P.S. For the 48 grain I calculate a sectional density of .106......so slightly below 2000 PSI would be the minimum pressure needed under ideal conditions for 950 FPS in a 24" barrel.
I am sizing the AV slugs to .250 as per the actual slugged Raptor bbl. Which is 22 not 24 inch. Twist has nothing to do with weight. Strictly length.
.254 is far too large in Dia. with huge friction which will kill fps.
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The barrel port must be enlarged. Factory is .167 unless recently changed. ;)
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.254 is far too large in Dia. with huge friction which will kill fps.
Oh so it does have a .250 groove diameter.
Here is what I posted earlier--> https://www.gatewaytoairguns.org/GTA/index.php?topic=171682.msg155932888#msg155932888 (https://www.gatewaytoairguns.org/GTA/index.php?topic=171682.msg155932888#msg155932888)
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.254 is far too large in Dia. with huge friction which will kill fps.
Oh so it does have a .250 groove diameter.
Here is what I posted earlier--> https://www.gatewaytoairguns.org/GTA/index.php?topic=171682.msg155932888#msg155932888 (https://www.gatewaytoairguns.org/GTA/index.php?topic=171682.msg155932888#msg155932888)
Yes Sir, and sing down to .250 (mine are .2497) will give a huge boost in velocity. ;)
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So there is more to the Raptor tune!
My guide earlier in the topic is still good to go. It can be used to find your MAX fps for given regulator pressure, with the MINIMUM amount amount of poppet lift, and JUST RIGHT amount of hammer spring.
Now its time to walk the tight rope!
Turn your hammer buffer in CW maybe 1/4 to 1/2 turn. Your FPS should drop. (Mine dropped about 30fps)
Now Turn your hammer spring adjuster CCW a little bit at a time until you find your MAX fps again.
Now that you have found your Max FPS setting again, its up to you to determine how far you want to be down the plateau, by turning your hammer spring adjuster CCW until desired FPS and Consistency is reached.
Notes:
I would not use the hammer buffer to tune on the knee of the bell curve. When I tried to do this My raptor didn't respond well, just increased my ES.
When turning up regulator, my shots started to drop in velocity once I was 400-500psi above the regulator setting I adjusted my hammer spring for.
After I did this to my Raptor, my shot report got a little more quiet. Even at 950 fps with 34gr jsb.
AND
I filled to 4350 and shot down to 2400. My FPS stayed within 955-935. MUCH better. I would get a lot of inconsistency when filling above 3500psi. This was probably due to very little poppet lift and regulator creep.
I am by no means an expert. This is just what worked for me.
Good luck guys!
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Thanks Jacob,
I will try that on mine tomorrow.
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Excellent results .... balanced valves are another Animal for sure !
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I would not use the hammer buffer to tune on the knee of the bell curve. When I tried to do this My raptor didn't respond well, just increased my ES.
I believe you are, in fact, tuned on the knee of the curve for the higher reg set-point. This because if you increased hammer spring your velocity would increase right?
EDIT: You are saying the best way to tune on the knee is keep hammer spring at some minimum acceptable level and then make adjustments by increasing reg pressure in steps. Yep, that can work.
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I would not use the hammer buffer to tune on the knee of the bell curve. When I tried to do this My raptor didn't respond well, just increased my ES.
I believe you are, in fact, tuned on the knee of the curve for the higher reg set-point. This because if you increased hammer spring your velocity would increase right?
EDIT: You are saying the best way to tune on the knee is keep hammer spring at some minimum acceptable level and then increase reg pressure in steps. Yep, that can work.
Thats what you do .... smallish steps in speed / velocity changes best done via Pressure changes at the regulator.
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I would not use the hammer buffer to tune on the knee of the bell curve. When I tried to do this My raptor didn't respond well, just increased my ES.
I believe you are, in fact, tuned on the knee of the curve for the higher reg set-point. This because if you increased hammer spring your velocity would increase right?
EDIT: You are saying the best way to tune on the knee is keep hammer spring at some minimum acceptable level and then increase reg pressure in steps. Yep, that can work.
Thats what you do .... smallish steps in speed / velocity changes best done via Pressure changes at the regulator.
Yes, small reg pressure changes followed by hammer spring changes as appropriate.
Actually I got to thinking perhaps reg pressure could be increased more than normal before making hammer spring changes in the case of switching to a high velocity (1050 FPS) aerodynamic projectile from a heavier and slower moving one. (re: even if valve dwell time decreased at the higher reg pressure it may not matter because the faster moving aerodynamic projectile is farther down the barrel than the slower moving and heavier one would have been.)
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My current Max FPS is 950fps and there is more then 1 way to get there.
Minimal Poppet lift : High hammer spring
Moderate Poppet lift : Medium hammer spring
Lots of poppet lift! : Low hammer spring.
When following the instructions you should end up on the “minimal” poppet lift setting.
And then make your way to the “moderate” setting. Which is where I believe the gun is most happy.
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I know it is NOT the way JSAR is doing it ... but having been around the balanced valves now nearly as long as anyone, likely manufactured more versions ( R&D ) than anyone have found that there are better ways and more stable miens to operate the firing system.
JSAR has approached a One Hammer does all with a One Valve does all with one Transfer Port does all .... While this certainly eases the manufacturing process and creates a uniform tuning procedure across ALL CALIBERS. it falls short of being ideal :( :(
Using a BUFFER hammer system where you have direct control over poppet lift is not without its shortcomings however.
Namely being UNDESIRABLE rebound if & when the hammer spring energy is too high and the hammer is violently slamming into the buffer ring. * It is of my opinion and that of many I've spoken with that it's use is a Crutch to allow having some control of the valves HEAVY BREATHING attributes.
My work around and how my personal guns using these valves ( versions of etc ... ) has been to use MUCH lighter hammers and control them via SSG spring devices.
* This also has a downside ... We loose the WIDE tuning range afforded by the factory configuration, but GAIN a lot more control being one can change hammer weight and spring force to a specific caliber and power setting. This eliminates the need for a buffer with a result the guns are far more stable being also a whole lot easier to get a solid tune.
** Also in this alternative set up I use TAPERED throat Transfer tubes to create sonic choking which also further help stabilize the output swings these easy opening valves experience.
Scott S
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Would lighter weight Marauder MDS hammers work?
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Would lighter weight Marauder MDS hammers work?
Not likely ... the hammers overall length is critical to the triggers reset mechanics as is the cocking lug position. with some fiddling you may be able to get something working but not sure.
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Took the raptor outside for the first time in a few days.
First shot over the chrony was 976 for 71fpe with the king heavy lol.
After that shot reg settled back down and the next 10 shots were all around 950fps.
Scary quiet , even at 71fpe!
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Took the raptor outside for the first time in a few days.
First shot over the chrony was 976 for 71fpe with the king heavy lol.
After that shot reg settled back down and the next 10 shots were all around 950fps.
Scary quiet , even at 71fpe!
Were you just checking the numbers? Or, are you also shooting targets? Would like to read your take on accuracy with slugs and/or pellets.
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I was checking numbers and also shooting casually at 100 yard 2 1/2 spinners.
It’s been a while since I shot at paper to check groups with the raptor. Now that I got a consistent tune, this will be the next step.
During my causal shooting I have had no problems hitting the 2 1/2 spinner , bottles, and pellet tins at 100 yards with 34gr jsb.
I have not found much success with NSA slugs. I need to give them another try.
I have had success with AVS slugs.
I need to order some of the promising slugs.
Really want to try HN, jsb and fx .25 slugs. Whenever they come out.
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Jacob, have you tried any Griffin slugs? So far, the Griffin TC 20gr (freebies) have given me the tightest groups (1/3” CC) so far with me tuning for only 18gr JSB’s since I received my Raptor back with retrofitted adjustable regulator. Mike, the owner said these should group tighter with a 950fps (the speed he knows they perform best at) and I shot them at a little over 900.
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The reg creep has me a bit concerned, hope it settles down!
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The reg creep is not that bad. Now that my gun is tuned properly, the first shot was only 26fps higher. Then the rest were consistent.
I’ve done some reading and it seems like many guns across different brands need 1 shot to clear the reg of any creep.
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The reg creep is not that bad. Now that my gun is tuned properly, the first shot was only 26fps higher. Then the rest were consistent.
I’ve done some reading and it seems like many guns across different brands need 1 shot to clear the reg of any creep.
I use to do a lot of benchrest shooting, with powder burns, and the first couple of shots where conditioners and to warm up the barrel before you would see consistent shots.
So now with air guns I just ignore the first of shots and treat them as conditioners. I'm sure that we would love to see no creep valves & regulators.
Even my expensive TIG and MIG gas regulators creep, to some degree, when setting on overnight.
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My Bantam Sniper HR (Huma Regulate) has been at 150 BAR since September 2019 and has not creeped at all. I’m lucky in that I get to shoot almost everyday. One of my routines is to take that first shot of the day. Whether at paper or a small object. Either at 40 or 50 yards. Which so far the gun passes with flying colors. During the course of my day I bring out the Bantam for a few shots here and there at small objects and can consistently get first round hits out to 66 yards. My gun continues to amaze me with its accuracy and consistency. I don’t believe creep is something you have to live with if you have a good regulator. All of my chronoed shot strings have SDs: under 10 FPS. Good luck with the Raptor.
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Ernest Rowe, who is a wonderful tuner of pcp’s said that if your regulator is not set to a higher working pressure then the first couple of shots could be off a little in fps...
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Set your velocity 5% below your max at a given set point and you won't have to worry so much about a little creep. Be sure your hammer energy can handle the first shot after a fill without ambient temp issues.
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** Also in this alternative set up I use TAPERED throat Transfer tubes to create sonic choking which also further help stabilize the output swings these easy opening valves experience.
Scott S
Is the smaller opening of the taper toward the barrel? Sounds like "sonic choking" is similar to the "venturi effect" that surfboard makers create with angled fins " / \" to cause the water going between them to increase speed.
Found this when looking up sonic choking..wonder if something like this could be incorporated into the porting system of airguns..
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In my situation, the only way the reg creep affects me now is my first shot will be 20-30 fps higher than the rest of my string. Not a big deal to me.
Set your velocity 5% below your max at a given set point and you won't have to worry so much about a little creep. Be sure your hammer energy can handle the first shot after a fill without ambient temp issues.
I found this very hard to do with the balanced valve. If I am currently shooting max 950fps and drop my fps down to + or - 905fps by adjusting the spring, I get a higher Extreme spread and more shot to shot variance.
If I keep it more tight, say 1-3% then ES is much better.
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I haven't played with my Raptor in it's current configuration to know if the adjustable reg creeps, so leaving that out of this and making general statements here.......
Most regs have some........performance issues that unregulated guns simply don't deal with.
My Veteran (the gun that everyone loves) has reg creep, or whatever else you like to call it. First shot will always be low fps. I know about it and blow off that first shot and life is good.
Regulation brings an increased level of complication and failure rate to a gun.
It's not a popular view, but for 99% of us airgunners, extreme spreads of less than 25 or so fps are not necessary, which means that neither are regulators. I'm taking about those of us that hunt or pest or even shoot paper in our yards. The current groundhog or starling doesn't care if it was killed with 12 more or less fps than the last one. And as far as impact points go, unless you're trying to make head shots on house sparrows at 125 yards, the difference in impact points due to fps changes within 25fps are neglible.
They do increase the tech level of a gun though, and open up further tinkering venues, all of which is the draw for some.
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I know it is NOT the way JSAR is doing it ... but having been around the balanced valves now nearly as long as anyone, likely manufactured more versions ( R&D ) than anyone have found that there are better ways and more stable miens to operate the firing system.
JSAR has approached a One Hammer does all with a One Valve does all with one Transfer Port does all .... While this certainly eases the manufacturing process and creates a uniform tuning procedure across ALL CALIBERS. it falls short of being ideal :( :(
Using a BUFFER hammer system where you have direct control over poppet lift is not without its shortcomings however.
Namely being UNDESIRABLE rebound if & when the hammer spring energy is too high and the hammer is violently slamming into the buffer ring. * It is of my opinion and that of many I've spoken with that it's use is a Crutch to allow having some control of the valves HEAVY BREATHING attributes.
My work around and how my personal guns using these valves ( versions of etc ... ) has been to use MUCH lighter hammers and control them via SSG spring devices.
* This also has a downside ... We loose the WIDE tuning range afforded by the factory configuration, but GAIN a lot more control being one can change hammer weight and spring force to a specific caliber and power setting. This eliminates the need for a buffer with a result the guns are far more stable being also a whole lot easier to get a solid tune.
** Also in this alternative set up I use TAPERED throat Transfer tubes to create sonic choking which also further help stabilize the output swings these easy opening valves experience.
Scott S
I'm always concerned about the wear and tear aspect of buffering. Especially in circumstances where I've fallen off the reg and not realized it. I hunt more than anything else, and probably 80% of that is at night.
** Also in this alternative set up I use TAPERED throat Transfer tubes to create sonic choking which also further help stabilize the output swings these easy opening valves experience.
Scott S
Is the smaller opening of the taper toward the barrel? Sounds like "sonic choking" is similar to the "venturi effect" that surfboard makers create with angled fins " / \" to cause the water going between them to increase speed.
Found this when looking up sonic choking..wonder if something like this could be incorporated into the porting system of airguns..
I ended up doing something like that with the valves that I made for my Taipan Vet. The first few that I made were just operating on the principals of opening up the porting for overcoming airflow restrictions, which yielded me around 25-30FPS (.217 / 25gr H&N slugs). When I incorporated multi-stage /\'s, velocity increased to almost 100FPS over the factory system. I was blown away, thinking I'd only see maybe 50 lol
That leads me to ask about the ideal porting sizes for the .30cal Raptors. I've decided to stick with ammo along the lines of Dale's 62gr Varmint Knockers (BHN-7) with the JSAR mags and given the smaller plenum I need to optimize the rifle for this caliber (I have plans for running it in smaller calibers btw).
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In case you missed this ... it may anwser some questions ???
See: https://www.gatewaytoairguns.org/GTA/index.php?topic=165159.msg155844248#msg155844248 (https://www.gatewaytoairguns.org/GTA/index.php?topic=165159.msg155844248#msg155844248)
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(I have plans for running it in smaller calibers btw).
Meant to say that I have NO plans running smaller calibers lol
In case you missed this ... it may anwser some questions ???
See: https://www.gatewaytoairguns.org/GTA/index.php?topic=165159.msg155844248#msg155844248 (https://www.gatewaytoairguns.org/GTA/index.php?topic=165159.msg155844248#msg155844248)
Good info! I've been dying to get a look inside on this Mini, but the o-rings that I was missing arrived in the mail today so I'm all in.
Hoping I'll have better luck in actually being able to remove the barrel with it disassembled. I don't think this one was turned down just right, it wouldn't budge more than a 1/2" when I tried to remove it :(
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In my situation, the only way the reg creep affects me now is my first shot will be 20-30 fps higher than the rest of my string. Not a big deal to me.
Set your velocity 5% below your max at a given set point and you won't have to worry so much about a little creep. Be sure your hammer energy can handle the first shot after a fill without ambient temp issues.
I found this very hard to do with the balanced valve. If I am currently shooting max 950fps and drop my fps down to + or - 905fps by adjusting the spring, I get a higher Extreme spread and more shot to shot variance.
If I keep it more tight, say 1-3% then ES is much better.
Jacob, very true about the balance valves..they like to BREATHE! LOL! That’s what they were made to do, shoot fast. I too cannot make mine shoot much slower with any consistency. I should just shoot heavy but I really like the 18gr JSB as they are relatively inexpensive but have to be shot over 950 to get consistent fps results which is paramount to consistent accuracy...even faster is better. Throwing slugs or 25gr JSB’s through her quiets her report down even at faster speeds.
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Cool, I got inside my Mini .30 finally I got several things done that were on my ToDo list, such as chucking my probe on my lathe to hand polish some of the chatter marks that have been bugging me (and possibly adding to my jamming issues with small slugs).
I also FINALLY got my barrel off. First thing I noticed was my barrel TP was a little off-center from the block ports, possibly from when I attempted to remove it the first time - but my witness marks were in perfect alignment ♂️ Also, there was indeed a little high point on the breech side of the barrel near the second grub screw divot that was making it a little too tight for the block, so I also hand polished the entire section turned down to 0.5000", and now it's not as painful to install / remove. Spent 2 hours polishing the barrel, cut a slightly deeper throat in the breech, and got it all put back together.
Repressurized it to 2K PSI and shot a few test shots, and nearly went deaf!!! I figured it would quiet back down once I turned the reg up some and retuned. I decided to stop around 2350psi for the 50gr JSBs. I loaded up a couple of mags with sorted pellets, and got it shooting 888 (literally 888 each shot), but it is definitely a bit louder now. Like a higher pitch than when I had it tuned like this before.
Now the one thing that I'm probably doing differently is I'm not leaning on the buffer much at all. The last step that I take in my tuning process is turning it in slightly and relying on my hammer settings to do all of the work. It used to have a deeper puff sound, but now my ears are ringing
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Cool, I got inside my Mini .30 finally I got several things done that were on my ToDo list, such as chucking my probe on my lathe to hand polish some of the chatter marks that have been bugging me (and possibly adding to my jamming issues with small slugs).
I also FINALLY got my barrel off. First thing I noticed was my barrel TP was a little off-center from the block ports, possibly from when I attempted to remove it the first time - but my witness marks were in perfect alignment ♂️ Also, there was indeed a little high point on the breech side of the barrel near the second grub screw divot that was making it a little too tight for the block, so I also hand polished the entire section turned down to 0.5000", and now it's not as painful to install / remove. Spent 2 hours polishing the barrel, cut a slightly deeper throat in the breech, and got it all put back together.
Repressurized it to 2K PSI and shot a few test shots, and nearly went deaf!!! I figured it would quiet back down once I turned the reg up some and retuned. I decided to stop around 2350psi for the 50gr JSBs. I loaded up a couple of mags with sorted pellets, and got it shooting 888 (literally 888 each shot), but it is definitely a bit louder now. Like a higher pitch than when I had it tuned like this before.
Now the one thing that I'm probably doing differently is I'm not leaning on the buffer much at all. The last step that I take in my tuning process is turning it in slightly and relying on my hammer settings to do all of the work. It used to have a deeper puff sound, but now my ears are ringing
Gino, very nice work! I wish I had those machining skills! Raptor’s are similar to Marauders and here is a link to tuning one different ways if you didn’t already know. Your sound signature sounds like a strong hammer spring tension with a short striker hit, hence the louder crisp report, with these adjustments, your fps consistency and efficiency will be excellent. With a light hammer spring adjustment and longer striker hit you get the much lower sound signature but consistency and efficiency suffers a little. You can tune in between easier with your .30...I have not much leeway with mine being a .22 with the balance valve and large plenum. Anyway, glad you have yours shooting well!
https://www.airgunnation.com/topic/tuning-a-marauder-what-to-adjust-and-where-to-start/ (https://www.airgunnation.com/topic/tuning-a-marauder-what-to-adjust-and-where-to-start/)
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Gino, very nice work! I wish I had those machining skills! Raptor’s are similar to Marauders and here is a link to tuning one different ways if you didn’t already know. Your sound signature sounds like a strong hammer spring tension with a short striker hit, hence the louder crisp report, with these adjustments, your fps consistency and efficiency will be excellent. With a light hammer spring adjustment and longer striker hit you get the much lower sound signature but consistency and efficiency suffers a little. You can tune in between easier with your .30...I have not much leeway with mine being a .22 with the balance valve and large plenum. Anyway, glad you have yours shooting well!
That's interesting, I've had regulated and unregulated Mrods / Prods - maybe that's why I haven't had too many issues getting ES tight. I'll have to spend some more time with my Mini and use some of that process to quiet it down. I can't shoot .30 "conveniently" for a while though :(
Thanks, I never connected those dots! 8)
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Gino, very nice work! I wish I had those machining skills! Raptor’s are similar to Marauders and here is a link to tuning one different ways if you didn’t already know. Your sound signature sounds like a strong hammer spring tension with a short striker hit, hence the louder crisp report, with these adjustments, your fps consistency and efficiency will be excellent. With a light hammer spring adjustment and longer striker hit you get the much lower sound signature but consistency and efficiency suffers a little. You can tune in between easier with your .30...I have not much leeway with mine being a .22 with the balance valve and large plenum. Anyway, glad you have yours shooting well!
That's interesting, I've had regulated and unregulated Mrods / Prods - maybe that's why I haven't had too many issues getting ES tight. I'll have to spend some more time with my Mini and use some of that process to quiet it down. I can't shoot .30 "conveniently" for a while though :(
Thanks, I never connected those dots! 8)
You’re welcome! Have fun.
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Jacob,
excellent tuning guide. I have had no need to adjust my Raptor HP .30, for my needs, it's perfect out of the box.
However, I just got a Mini and so am attempting to tune it and have questions on your terminology.
1. Hammer Adjuster
2. Hammer Buffer
3. Hammer Spring Adjustment
With no guide, explanation, or pictures, all I know at this time is that I can adjust the Hammer Spring with an 8mm allen wrench. You state, "...Hammer Adjuster where it is recessed into the adjustment range. 2 or 3 threads should be visible..." Where is this?
Thanks
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I tore down my Reg today and refinished the nylon ball, along with installing the new one piece poppet. Nice!!! No creep, dead nuts accurate evening the bad north wind coming straight in. Shot like a match gun! Many, many .1 and .2 Inch groups at both 50 and 80 yards with my handj cast hp's. Did an expansion test, most were well over .375" FROM THE LOLEY .22. at 70 fpe Woo-Hoo!!!
Knife
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I tore down my Reg today and refinished the nylon ball, along with installing the new one piece poppet. Nice!!! No creep, dead nuts accurate evening the bad north wind coming straight in. Shot like a match gun! Many, many .1 and .2 Inch groups at both 50 and 80 yards with my handj cast hp's. Did an expansion test, most were well over .375" FROM THE LOLEY .22. at 70 fpe Woo-Hoo!!!
Knife
I wished I lived close! Impressive. Maybe you can share your voodoo.