GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Tack Driver 10 on July 24, 2018, 09:05:34 PM
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Ordered a CCS 2400KT during their July sale and received it today.
Has a 14.5" LW 17 cal barrel.
Cleaned the barrel and ran it over the chrony.
With 7.9 CPHPs got an average 610 FPS, 6.52 FPE.
A little disappointing but has a narrow .130" barrel port and the TP was leaky.
While waiting for the gun to arrive I modded a spare valve.
Bored the throat from .220" to .250".
Drilled the TP opening to .173" and countersunk port to 1/4".
Ported the valve at the TP.
Cut the valve seat to 135 degrees.
Made a Delrin valve stem from drill blank.
Did not make any volume mods as I wanted higher shot count.
With the modded valve and an 18" Crosman barrel with a .165 port:
Got 635 FPS, 12.80 FPE with 14.3 CPHPS at 78 degrees.
With volume mods, 24" barrel, heavy hammer spring and extended probe 720 FPS, 16.5 FPE is very doable.
More mods to come.
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May I assume that the 18 and 24 inch barrels are in .22 cal ? It seems many mods aren’t proportional between calibers.
But what a fun platform !
Congratulations!
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Just finished a 2400 KT in .177cal. It has an 18" Crosman barrel with a 6.5 TKO.. Converted it to HPA beause of fall and winter shooting last year being difficult at best with changing temps. Used a 2600 tube and fill set from Crosman parts, same triggef set polished & lightened up. Did the 3 bolt pattern to secure valve body. Used a disco valve, I modified with angled port and a p-rod stem. Supported by a small peice of brass hobby tubing to make it fit. (thanks Bob) Bstasley o-rings. It shoots about 20 shots in the low 900 fps range. Couldn't be happier. Good luck with yours. I'm interested in that 14"Walther barrel in. 22. Bet that makes a fine short carbine that shoots lights out. Keep us posted.
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The 18" and 24" barrels are 22 cal.
HPA is the way to go and I've always wanted a P-Rod so one may be in my future.
Installed an extended probe and a heavier hammer spring.
It's a 2100 spring cut down to the same length as the stock spring.
May make a power adjuster but for now this works good.
All tests run at 78 degrees.
with Crosman 14.3 grain CPHPS= 647 FPS, 13.29 FPE
with H&N Barracuda Hunter Extreme 18.52 grain HPs= 587 FPS, 14.17 FPE
with JSB Jumbo Beast 33.956 grain pellets= 458 FPS, 15.81 FPE
Next I'll see how many shots the gun will get from a cartridge.
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So why did ya order a 14.5" LW 17 cal barrel ???
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Made some more progress.
Worked on the stock trigger using a reworked 1701 trigger blade.
Polished and shimmed the sear, replaced the stock pins with #30 drill blank.
Lighter spring with Teflon retainer.
Brass safety.
Made a PA and extended brass probe/bolt.
The probe diameter is .257" as opposed to the loose .250".
Cocks buttery smooth now.
The silencer keeps it stealthy.
Have a wood TH stock that will get final fitted soon.
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All dressed up with the LW 14" barrel in 17 cal.
Balances nicely at the loading port.
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Nice stock, TD! Did you make that?
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Nice stock, TD! Did you make that?
I made the stock from 1/2" poplar sourced from Lowes.
It's made in 3 pieces that are glued together as you can see below.
The 1/2" is ideal as the trigger frame is also 1/2" thick.
Once it's glued up you just remove everything that doesn't look like a stock.....LOL
Lots of shaping and sanding.
I have some 1/2" black walnut and want to make a few walnut sandwiched red oak versions.
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That stock is rad. Very nice work!
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Love your work... as always.
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Here's an outline of how to make the stock.
https://www.gatewaytoairguns.org/GTA/index.php?topic=146554.new#new (https://www.gatewaytoairguns.org/GTA/index.php?topic=146554.new#new)
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So whats it shooting now with your .177 and valve mods?
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Ingenious!
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So whats it shooting now with your .177 and valve mods?
Last week the experimental Delrin valve stem released all the CO2 after shooting several shots with the heavy hammer spring.
The Delrin is pressed on but moved forward on the shaft so I machined a groove and installed a circlip.
A bit like micro surgery but the patient is doing fine.
The clip is .015" thick so ordered some .009" jewelry/dental discs to make the groove.
Put it back in the gun along with the heavy hammer spring.
Ran it over the chrony this morning:
All tests run at 78 degrees.
1. 7.90 CPHP, 655 FPS 7.52 FPE
2. 7.90 CPHP, 651 FPS 7.43 FPE
3. 7.90 CPHP, 651 FPS 7.53 FPE
4. 9.57 H&N Barracuda Hunter Extreme, 626 FPS 8.33 FPE
5. 9.57 H&N Barracuda Hunter Extreme, 627 FPS 8.35 FPE
6. 10.65 H&N Barracuda Match, 601 FPS 8.54 FPE
7. 10.65 H&N Barracuda Match, 606 FPS 8.68 FPE
8. 8.20 RWS Superpoint, 676 FPS 8.32 FPE
9. 8.20 RWS Superpoint, 666 FPS 8.07 FPE
10. 8.44 JSB Exact, 651 FPS 7.94 FPE
11. 8.44 JSB Exact, 651 FPS 7.94 FPE
12. 8.44 JSB Exact, 652 FPS 7.96 FPE
13. 8.44 JSB Exact, 646 FPS 7.82 FPE
14. 8.44 JSB Exact, 629 FPS (Drop off)
One thing that I noticed is with the Delrin stem the velocities are very consistent.
With the original stem they varied by 20 FPS over a 5 shot string.
Possibly due to the soft seal material or the roughly machined shaft.
Got 13 good shots before dropping off.
Will try the stock light hammer spring and look at the velocity and shot count.
17 cal with a 14" barrel shouldn't need the heavy spring and is probably wasting gas.
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Ran the gun over the chrony Saturday with the original hammer spring.
14.5" LW barrel in 17 cal
Notice how consistent the groups are especially shots 11-18.
I have a Delrin valve stem and a 90 duro poly bumper on the back of the valve that limits
the stem travel to .105".
All tests run at 78 degrees.
1. 7.90 CPHP, 651 FPS 7.43 FPE
2. 7.90 CPHP, 644 FPS 7.27 FPE
3. 7.90 CPHP, 646 FPS 7.32 FPE
4. 7.90 CPHP, 647 FPS 7.34 FPE Average
5. 7.90 CPHP, 654 FPS 7.50 FPE
6. 8.3 RWS SuperDome, 638 FPS 7.50 FPE
7. 8.3 RWS SuperDome, 637 FPS 7.48 FPE
8. 8.3 RWS SuperDome, 632 FPS 7.36 FPE Average
9. 8.3 RWS SuperDome, 630 FPS 7.31 FPE
10. 8.3 RWS SuperDome, 623 FPS 7.15 FPE
11. 9.57 H&N Barracuca Hunter Extreme, 610 FPS 7.90 FPE
12. 9.57 H&N Barracuca Hunter Extreme, 611 FPS 7.93 FPE
13. 9.57 H&N Barracuca Hunter Extreme, 613 FPS 7.98 FPE
14. 9.57 H&N Barracuca Hunter Extreme, 611 FPS 7.93 FPE Average
15. 9.57 H&N Barracuca Hunter Extreme, 614 FPS 8.01 FPE
16. 9.57 H&N Barracuca Hunter Extreme, 614 FPS 8.01 FPE
17. 9.57 H&N Barracuca Hunter Extreme, 607 FPS 7.83 FPE
18. 9.57 H&N Barracuca Hunter Extreme, 612 FPS 7.96 FPE
19. 9.57 H&N Barracuca Hunter Extreme, 596 FPS 7.55 FPE Dropoff
20. 9.57 H&N Barracuca Hunter Extreme, 592 FPS 7.45 FPE
I prepped a CCS 22 cal 14.5" LW barrel today with a .157 barrel port
so I'll be testing it in the next few days.
I think it will come in at around 11-12 FPE depending on the pellet.
Hopefully it will also be as consistent as the 17 cal is.
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Made this self piercing valve top from a spare 1077 plug.
Turned it down, threaded it and cut the o-ring gland.
The plug is P/N 1077-036.......$12.00
Used a modified Mrod valve stem.
Valve port is .166".
I'll get it in the gun over the weekend for testing.
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Put the 14.5", 22 cal CCS LW barrel on the gun earlier this week and ran a full CO2 cart.
Heavy hammer spring backed out .250" on the PA.
Barrel port .157".
Average 10.60 FPE and very consistent.
All tests run at 78 degrees.
1. 14.30 CPHP, 583 FPS 10.79 FPE
2. 14.30 CPHP, 571 FPS 10.35 FPE
3. 14.30 CPHP, 575 FPS 10.50 FPE
4. 14.30 CPHP, 570 FPS 10.31 FPE
5. 14.30 CPHP, 568 FPS 10.24 FPE
6. 18.52 H&N Barracuda Extreme, 515 FPS 10.90 FPE
7. 18.52 H&N Barracuda Extreme, 519 FPS 11.07 FPE
8. 18.52 H&N Barracuda Extreme, 517 FPS 10.99 FPE
9. 18.52 H&N Barracuda Extreme, 510 FPS 10.69 FPE
10. 18.52 H&N Barracuda Extreme, 512 FPS 10.78 FPE
11. 18.52 H&N Barracuda Extreme, 512 FPS 10.78 FPE
12. 18.52 H&N Barracuda Extreme, 508 FPS 10.61 FPE
13. 18.52 H&N Barracuda Extreme, 506 FPS 10.53 FPE
14. 18.52 H&N Barracuda Extreme, 510 FPS 10.69 FPE
15. 18.52 H&N Barracuda Extreme, 505 FPS 10.48 FPE
16. 18.52 H&N Barracuda Extreme, 506 FPS 10.53 FPE
17. 18.52 H&N Barracuda Extreme, 508 FPS 10.61 FPE
18. 18.52 H&N Barracuda Extreme, 506 FPS 10.53 FPE
19. 18.52 H&N Barracuda Extreme, 497 FPS 10.15 FPE
20. 18.52 H&N Barracuda Extreme, 488 FPS 09.79 FPE Dropoff
Made a wood fore grip to replace the plastic version.
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Installed the self piercing valve in the gun and ran some tests.
All tests run at 78 degrees.
With the 14.5" LW 22 cal barrel got a small gain of 1-2 FPE with 8 strong shots.
12.08 FPE with 18.52 grain H&N Barracuda Hunter Extreme pellets.
This valve holds a lot more gas so I cut to the chase and
installed a 22 3/4" Crosman 22 cal barrel with a .166" port.
Still got 8 strong shots but the gun came alive.
14.3 CPHP........................................706 FPS 15.82 FPE
18.52 H&N Barracuda Hunter Extreme 653 FPS 17.53 FPE
33.96 JSB Jumbo Beast.....................505 FPS 19.23 FPE
Today I put the 18" Crosman 22 cal .165" port barrel on the gun.
Tested with 2100 hammer spring cut to same length as original spring.
14.3 CPHP Not tested
18.52 H&N Barracuda Hunter Extreme..600 FPS 14.82 FPE
With the stock hammer spring got........593 FPS 14.46 FPE
33.96 JSB Jumbo Beast.......................479 FPS 17.30 FPE
I'll stay with the 18" barrel for now and experiment with lighter hammer and springs.
Stock, this gun wastes a lot of gas since it has to pierce the cart.
I'd like to get the shot count to around 20+ with decent power.
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Coming around nicely... (http://www.chevelles.com/forums/images/smilies/thumbsup.gif)
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When testing and posting your shot strings, You should add the temperatures to your posted strings, When shooting Co2 ;) It will really help those in warm area's like Oklahoma 8) Lucky Dog!! I'm in mid Michigan ??? and the low tonight is 63. I only have one Co2 left, just to short of a warm season here, With lots of ups & downs. The rest have been converted over to 13ci Ninja regulated bottle's HPA for better consistency here. The old sheridan pumps are still real popular here.
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Good point.
All the testing is done at 78 degrees.
I'll update the posts, thanks.
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Tested the gun with the stock hammer/spring backed off 6T or .250" on the PA.
18" Crosman 22 cal barrel with .165" port.
Used 14.3 CPHPs and ran it until it dropped off to get a baseline.
Still amazed at how consistent the shot string is.
Only 11 FPS deviation shots 1-18.
A carpenters dream, flat as a board and straight as a nail.....LOL
Tested at 78 degrees, 3 minute shot cycle.
01. 637 FPS 12.88 FPE
02. 639 FPS 12.96 FPE
03. 635 FPS 12.80 FPE
04. 637 FPS 12.88 FPE
05. 638 FPS 12.92 FPE
06. 628 FPS 12.52 FPE
07. 636 FPS 12.84 FPE
08. 638 FPS 12.92 FPE
09. 633 FPS 12.72 FPE
10. 636 FPS 12.84 FPE
11. 635 FPS 12.80 FPE
12. 637 FPS 12.88 FPE
13. 637 FPS 12.88 FPE
14. 636 FPS 12.84 FPE
15. 632 FPS 12.68 FPE
16. 634 FPS 12.76 FPE
17. 636 FPS 12.84 FPE
18. 638 FPS 12.92 FPE
19. 624 FPS 12.36 FPE
20. 616 FPS 12.05 FPE Dropoff
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Installed the 17 cal 14.5" CCS LW barrel.
Elongated the barrel port .125" wide x .210" long.
Valve and TP remain .170".
Tested at 78 degrees, 1200' altitude.
With the stock hammer spring -6 turns:
9.57 Barracuda Hunter Extreme 647 FPS 8.89 FPE
20 shots at this power level.
Stock spring all in:
9.57 Barracuda Hunter Extreme 663 FPS 9.34 FPE
At 20 yards will pass through both sides of a steel food can.
If it'll go through a can it'll go through a squirrel as well.
Trigger adjusted at 1 lb pull.
Very accurate also.