GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: rsterne on January 24, 2016, 03:58:53 PM
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Here is something that might be fun.... How about an informal contest using a STOCK Crosman 2240 equipped with an SSG.... The goal is to get the most energy from a single 12 gram CO2 cartridge, shooting at room temperature.... Since it's my idea, I'll write the rules....
You must use a Stock Crosman 2240 except for the following items, in italics, which may have any configuration....
Hammer
Hammer Spring(s)
Rear End Cap, with or without adjuster(s)
Spring Guide (optional)
SSG of whatever design you like (optional)
Additional Rules:
You must use a stock 7.5" barrel in .22 cal, with stock ports.
You must use a stock 2240 valve, with stock ports and no insert to reduce the volume, with stock valve spring, poppet and piercing pin.
You must use a stock 0.140" transfer port and seal.
You must use a stock Crosman 2240 breech and bolt OR the factory replacement 22XX steel breech and bolt, and a stock cocking pin, which must cock the gun.
You must use a stock 2240 main tube and front cap.
You must use a stock 2240 trigger assembly OR the PRod or 1701 trigger assembly, it can be modified for lighter pull weight, sears polished etc.
You must use a single, new, standard 12 g. CO2 cartridge for each shot string.
The temperature must not exceed 75*F, and you must shoot at least 1 shot per minute.
You must record the velocity of every shot, and the pellet weight. "ERR" will count as zero velocity.
You must post a description and photo of the SSG configuration you used.
If it isn't in one of the above lists (allowed or not allowed), PM me and I will make a ruling and post it.... Any additions/clarifications will be posted in blue....
The winner will be the person who achieves the highest total energy (FPE) from a single CO2 cartridge.... The FPE of each shot will be calculated and the sum used.... There is no limit to the number of strings you shoot, but please, only submit your BEST shot string, to make it easier to keep track.... The honour system will be used....
I don't currently have a stock 2240, and I will not be competing in this contest, so I can be an impartial judge.... What do you think, is anyone interested?.... How about we let the contest run until the 28th of February.... and I will announce the winner on Leap Years.... There is no prize, other than the satisfaction of the accomplishment....
Bob
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Why the stock trigger? Would modding for lighter trigger increase shot count? I just bought a 40 count Co2 pack yesterday, so this sounds interesting. Garage is only 55f right now, so it needs to warm up a little.
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Good point, changed the rules to accommodate.... I wanted the gun to be recognizable as a 2240....
Bob
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i think this would be a great idea and way to compile alot of info. i wish i could join in on this.
note..since you're talking 2240 perhaps a duplicate post in the crosman gate would get more attention. i thought guys would be all over this.
peace
kj
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I may be the only one that owns a stock one! I am booked till after the 14th, but Then I will hit it hard. I have to believe this may be the perfect place for it. I will also try with a 10" .177 barrel when I am done.
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Added a simple SSG to a 2300 kt from the custom shop with a 10.1" barrel. Would this be disqualified from displaying any efficiency gains for this competition?
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Added a simple SSG to a 2300 kt from the custom shop with a 10.1" barrel. Would this be disqualified from displaying any efficiency gains for this competition?
That 10.1 barrel is in .177 - rules say 7" in .22, so I'd say "DQ".
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Its a .22, thats how I ordered it from the Custom Shop. Everything is bone stock and the same as a 2240.
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Did try a 10" on mine...velocity went up to ~420fps +/-@ 58F...did not shoot a full string. Velocity increase means I'm still using more co2 than needed for the stock barrel....and there is still room for improvement. :D
Would like to see your string...maybe a thread for just that? (SSG shot string thread)
Al
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Its a .22, thats how I ordered it from the Custom Shop. Everything is bone stock and the same as a 2240.
Didn't realize they made a 10.1" barrel in .22, (I always look at the 2400 offerings, not the 2300) but I'd still say that it's 3.1" longer then the "rules", so still DQ.
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Must be a stock 7.5" .22 cal barrel, and a 2240 valve for this challenge.... Longer barrels, different calibers, and valves that may have inserts will all change the FPE results from a 12 g. cartridge.... While as Gippeto says, before and after Chrony strings are interesting and enlightening/informative.... we have to stick to these rules for this thread....
Bob
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Okeydokey,
Just thought a little less arbitrary rules might open it up for some more folks to participate and make things interesting. See ya somewhere else.
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Pretty simple, just start your own thread.... You can't compare a 10.1" barrel to a 7.5" any more than an apple to an orange.... except they are both round.... I'm just as interested in your results as any....
Bob
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Mr. Sterne,
How much coffee did you drink the day you wrote the rules...or was it something a little stronger? 8) Why not just let everyone do whatever modification they choose to see who can come up with the most fpe from one Co2? If a guy wants to put a 28" barrel or whatever else he should be able to do it. Now that would be a fun contest! Some real fun Frankenstein guns would be built and everyone might learn something too. The way you are rigging up the rules there is no doubt that you will be the winner...but who even cares? Dude, try some decaf!
Best regards, Chuckster
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The way you are rigging up the rules there is no doubt that you will be the winner...but who even cares? Dude, try some decaf!
Best regards, Chuckster
Chuckster - apparently you failed to read his entire post
I don't currently have a stock 2240, and I will not be competing in this contest, so I can be an impartial judge...
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No comment....
Bob
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Mr. Sterne,
How much coffee did you drink the day you wrote the rules...or was it something a little stronger? 8) Why not just let everyone do whatever modification they choose to see who can come up with the most fpe from one Co2? If a guy wants to put a 28" barrel or whatever else he should be able to do it. Now that would be a fun contest! Some real fun Frankenstein guns would be built and everyone might learn something too. The way you are rigging up the rules there is no doubt that you will be the winner...but who even cares? Dude, try some decaf!
Best regards, Chuckster
. Really?
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darn this is a nice thread and subject , i dont have a 2240 but in a way i can compare how the ssg works in oir co2 rigs here in the tropics
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Well actually I did not read the entire post and add on...sorry Bob! Please accept my heartfelt apology...
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I'm going to pick one up just to try. I've got a few ideas to toss around, though probably nothing original or new. I like the idea of this competition as it puts those with relatively basic tools on the same playing field as those who can mill out or toss a bunch of cash at the project. More of an Everyman competition than all out mod war. Worst come to worst I'll copy the winners setup and have a very effcient setup and a fun little pistol.
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Bob, one thing I noticed and don't know if it will make a difference.
The 2240 that I just got has a different hammer than my previous ones. This one (I think) was made in 2015 and came with a notched hammer.
I don't have a scale to weight the two for comparison but there's probably a slight difference which may effect comparing results between "stock" hammers.
Blue
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see the first rule.... any hammer you want....
Bob
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Sorry Bob, totally had that wrong side up in my head.
Thanks,
Blue
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Here is something that might be fun....
Bob
Bob, that may prove to be the understatement of the year.
I've got to revise my design at some point (which is fine as I'll need to make more so ALL my 22xx bases can have them) because I'm sure there's drag in my system that can be improved. That being said, I'm having a hoot looking at the improvements I'm seeing already. I took a baseline of the fresh 2240 before starting to play with the SSG and my figuring showed it got around 115, maybe 120 total FPE out of the fresh cart in it's true "stock" configuration. I still have some playing around to do but I'm pretty shocked at what the SSG has done so far.
I can't find enough time to "play" with this, it's my new favorite toy!
Fun stuff indeed. Looking forward to seeing what everyone is getting.
Blue
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Many years ago, with a 1750 and careful tuning I exceeded 600 FPE from a single CO2 cartridge.... Bear in mind this was with an 18" barrel in .177 cal, and has NOTHING to do with this challenge....
(http://i378.photobucket.com/albums/oo221/rsterne/1750%20with%20DPH/WebShotStringsDPH9.jpg) (http://s378.photobucket.com/user/rsterne/media/1750%20with%20DPH/WebShotStringsDPH9.jpg.html)
Check out the blue line, with over 130 shots at over 510 fps average with 7.8 gr. pellets.... IIRC, the total was about 608 FPE at 75*F.... That was the record at the time, and I haven't heard of anyone breaking it since.... Incidently, if you expand the CO2 in a 12gr. cartridge to a gas at room temperature, it works out to almost exactly 400 cu.in.... An output of 400 FPE total is 1.0 FPE/CI.... so I was over 1.52 FPE/CI on CO2....
Bob
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Here are my results (after many tweaks and even more strings run).
The only thing I used that didn't come with the 2240 was the TKO and the SSG unit that I made for testing (and some white paint on the grips but they ARE the stock grips).
(http://i1305.photobucket.com/albums/s543/timbyb/image_zpsqy8tyyzu.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zpsqy8tyyzu.jpeg.html)
The hammer that came stock with this 2240 was notched and that's the one I used. All my previous 22xx's came without the notch.
"Old" style hammer on left, "new" notched hammer on the right.
(http://i1305.photobucket.com/albums/s543/timbyb/image_zps7yccyu7p.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zps7yccyu7p.jpeg.html)
Here's the baseline string I ran before starting work with the SSG.
Using 14.3gr CPHP, shooting approximately 1 shot every 20 seconds. Ambient temp was around 65 deg F.
# Velocity FPE
1. 364.4. 4.2
2. 364.0. 4.2
3. 362.7. 4.2
4. 361.2. 4.1
5. 359.8. 4.1
6. 362.3. 4.2
7. 365.1. 4.2
8. 366.4. 4.3
9. 367.0. 4.3
10. 363.0. 4.3
11. 369.5. 4.3
12. 364.7. 4.2
13. 365.0. 4.2
14. 370.3. 4.4
15. 365.0. 4.2
16. 362.3. 4.2
17. 355.9. 4.0
18. 353.8. 4.0
19. 349.5. 3.9
20. 345.3. 3.8
21. 340.2. 3.7
22. 337.1. 3.6
23. 337.0. 3.6
24. 333.6. 3.5
25. 329.2. 3.4
26. 317.7. 3.2
27. 299.3. 2.8
28. 279.4. 2.5
29. 254.6. 2.1
30. 224.0. 1.6
31. 186.6. 1.1
Total FPE=114.3
Here are the pictures of the SSG I used during testing. I had trouble getting the hole bored exactly in the center of the bolt which does leave some drag at certain positions when making adjustments. I'm currently working on a couple more SSG's and I hope to make future versions a little cleaner.
(http://i1305.photobucket.com/albums/s543/timbyb/image_zpsvex8rvpu.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zpsvex8rvpu.jpeg.html)
(http://i1305.photobucket.com/albums/s543/timbyb/image_zpskfyerbro.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zpskfyerbro.jpeg.html)
The spring is from Ace Hardware's bin of compression springs (I can't be positive that the one in the picture above is the spring from the final setting). It started out longer and was clipped down during testing. It is (I think) a .025" wire with a smaller OD than "stock" (around 1/4" OD) clipped to 13 coils leaving an uncompressed length of approximately 1 3/8" and compressed under pre-load to 15/16". Gap was set to (approx) 1/16".
Edit: added pictures of spring
Top spring is before clipping coils, bottom spring is the one used for the string I'm submitting.
(http://i1305.photobucket.com/albums/s543/timbyb/image_zpsa4fkawzb.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zpsa4fkawzb.jpeg.html)
Trying to show the (smaller) OD of the spring used
(http://i1305.photobucket.com/albums/s543/timbyb/image_zps1kijzmx1.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zps1kijzmx1.jpeg.html)
Showing wire diameter
(http://i1305.photobucket.com/albums/s543/timbyb/image_zpslnlmrefj.jpeg) (http://s1305.photobucket.com/user/timbyb/media/image_zpslnlmrefj.jpeg.html)
Here's the string with the SSG:
Again using 14.3gr CPHP, approx. 65*F, shooting approx. 1 shot per 15 seconds.
# Velocity FPE
1. 355.2. 3.96
2. 365.3. 4.23
3. 362.6. 4.18
4. 363.1. 4.18
5. 361.6. 4.16
6. 356.4. 4.02
7. 356.3. 4.02
8. 358.8. 4.09
9. 354.8. 4.0
10. 343.4. 3.74
11. 348.9. 3.87
12. 348.5. 3.87
13. 347.3. 3.82
14. 355.5. 4.02
15. 350.9. 3.91
16. 355.6. 4.02
17. 356.8. 4.05
18. 354.5. 4.0
19. 350.1. 3.89
20. 357.1. 4.05
21. 356.8. 4.05
22. 359.1. 4.09
23. 355.0. 4.0
24. 351.5. 3.93
25. 354.2. 3.98
26. 357.1. 4.05
27. 354.7. 4.0
28. 356.0. 4.02
29. 357.7. 4.07
30. 362.0. 4.16
31. 360.1. 4.11
32. 355.8. 4.02
33. 360.0. 4.11
34. 348.2 3.87
35. 348.2. 3.85
36. 358.6. 4.09
37. 362.1. 4.16
38. 354.9 4.0
39. 360.6. 4.14
40. 363.2. 4.18
41. 359.0 4.09
42. 358.0. 4.07
43. 365.0. 4.23
44. 364.5. 4.23
45. 362.0. 4.16
46. 364.6. 4.23
47. 365.4. 4.23
48. 365.1. 4.23
49. 361.5. 4.16
50. 366.9. 4.28
51. 365.4. 4.23
52. 365.1. 4.23
53. 366.5. 4.25
54. 366.0. 4.25
55. 368.7. 4.32
56. 361.6. 4.16
57. 362.0. 4.16
58. 365.4. 4.23
59. 373.0. 4.42
60. 366.9. 4.28
61. 370.5. 4.37
62. 367.0. 4.28
63. 366.8. 4.28
64. 367.1. 4.28
65. 366.5. 4.28
66. 368.2. 4.3
67. 366.5. 4.28
68. 362.5. 4.17
69. 366.8. 4.28
70. 365.5. 4.25
71. 367.1. 4.28
72. 367.1. 4.28
73. 368.2. 4.3
74. 368.0. 4.3
75. 366.1. 4.25
76. 365.0. 4.23
77. 366.3. 4.25
78. 363.2. 4.18
79. 366.5. 4.28
80. 365.0. 4.23
81. 365.4. 4.23
82. 371.9. 4.39
83. 370.8. 4.37
84. 364.6. 4.23
85. 359.4. 4.09
86. 366.5. 4.28
87. 368.2. 4.3
88. 367.1. 4.28
89. 361.0. 4.14
90. 359.0. 4.09
91. 351.4. 3.91
92. 352.0. 3.93
93. 344.3. 3.76
94. 338.3. 3.63
95. 334.0. 3.54
96. 323.9. 3.33
97. 313.6. 3.13
98. 309.8. 3.05
99. 300.0. 2.86
100. 290.1. 2.67
101. 283.1. 2.54
102. 270.2. 2.31
103. 264.5. 2.23
104. 261.3. 2.16
105. 251.5. 2.02
106. 245.0. 1.91
107. 236.4. 1.77
108. 228.0. 1.65
109. 221.9. 1.56
110. 212.4. 1.43
111. 196.5. 1.23
112. 182.4. 1.06
113. 170.3. 0.92
114. 161.1. 0.82
115. 150.5. 0.72
116. ERR. 0
117. ERR. 0
118. ERR. 0
Total FPE=431.34
Please excuse me if my math skills are off, I'll double check my numbers after posting and make any necessary edits. I just wanted to get my post in and that was a lot of numbers to keep straight while transcribing the data over.
I can't wait to see what other people have come up with.
Thanks for the challenge Bob!
Blue
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You went from 26 shots over 300 fps to 99.... nearly 4 times as much.... and nearly 4 times as much total energy as well.... Kind of reduces the cost of using CO2, HUH?.... If you only count the shots at over 4 FPE, you have 5 times as many.... 90 compared to 18.... :o
Well done.... I hope we get a few more entries.... ::)
Bob
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Ok im in now! Just got one in the shop stay tuned.
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Thanks Bob!
Here's a couple thoughts I had while testing this rig.
I can feel some bind in my SSG which is manageable for now but if done slightly better would possibly even things out more and thus add to the efficiency. Also better (or sorted) pellets may also slightly boost the numbers if you're looking for less deviation from shot to shot.
I wanted to keep things as "stock" as possible (i.e. not changing the hammer weight or style) to see what ONLY adding the SSG with a different spring would do. Again, if looking to find the "best" string possible, playing with the hammer might be next on my list.
Interesting but probably not relevant was that it seemed to be most efficient at around 4.2 FPE which I think was close to the energy output for your crazy efficient .177 record above.
I'll be playing around with this for a while getting things dialed in for my other 22xx platforms. I can't wait to see what happens when we step away from "stock" and start seeing what happens when tinkering with the valve, ports, and barrel length get thrown into the mix.
Blue
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Blue, did you notice I broke my own record recently in the SSG thread.... I'm now at 627 FPE from a single 12 gr. cartridge, in .22 cal with 18.1 gr. pellets and a 24" barrel.... Post #728 on page 37...
Bob
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Kind of reduces the cost of using CO2, HUH?...
Yeah, those test strings just went on and on and on.
I'm going to have to figure out a new system for keeping track of how many shots into a cart I am.
Blue
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Blue, did you notice I broke my own record recently in the SSG thread.... I'm now at 627 FPE from a single 12 gr. cartridge, in .22 cal with 18.1 gr. pellets and a 24" barrel....
Bob
You are a genius with too much time on your hands.
Please continue because a bunch of people are going to stand on your shoulders and you'll just elevate the position we get to start from.
Blue
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thank for the info sirs.
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And the winner (and only contestant) is....
BLUE
Congratulations, Sir, on showing the gains possible on CO2 by using an SSG.... Well Done !!!
Bob
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Blue did a good job but you did not wait for Travis. Not fair! ;)
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Thanks Bob, this was more eye openning than I anticipated and a lot more fun than I could have hoped for!
I'm pretty sure your overall record is safe but I can't wait to see mine broken!
Blue
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Congrats Blue, the only guy around that still has a stock 2240. ;D :o Great information on the SSG.
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Contest, as per posted rules, ended last night....
Bob
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Contest, as per posted rules, ended last night....
Bob
I missed that, my appologies.
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since those shots were so consistant, ill bet accuracy was great as well? is that what you would strive for in say a stock 10 m gun? the thought of 100 or so shots to 1 co2 is insane but yet makes me think if its that consistant what that can do for accuracy. im not much of a tinkerer yalls minds are way above mine but for the average shooter like me you can get alot of shooting in. thanks for all that valuable info men
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since those shots were so consistant, ill bet accuracy was great as well?
I would imagine that the shot to shot consistancy would indeed help with accuracy.
Unfortunately I wasn't really paying attention to accuracy when testing. Accuracy wasn't horrible with the stock barrel but wasn't competition quality. I have another 2240 that IS very accurate but I had to work the crown and leade to get it there.
Also the pellets used for testing were inexpensive and unsorted Crosman Premier Hollow Points which can vary in size and weight so a more consistently sized pellet should also help with accuracy.
Right now I'm working on incorporating a SSG into a 1740 with a LW barrel which I'm hoping will become a VERY consistant shooter for target work.
Blue
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im apologizing in advance but i have not been following 2240 R&D... what is a SSG? how does it work? again, i tried to search it but there are way too many posts on it and cant find the origin to be able to understand what it is... (or what does SSG stand for, for that matter...). Could someone give me a bit of help?
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SSG = Stopped (or Stopping) Spring Guide
Developed by Bob Sterne, he's got a monster post all about it's development. Started out with mostly pcp platforms. Bob put out the New Years challenge to see what could be done with a (basically) stock 2240 and the addition of a SSG.
Here's a post I started for people to contribute to the further refinement for the 22xx platform.
http://www.gatewaytoairguns.org/GTA/index.php?topic=105520.msg1000343#msg1000343 (http://www.gatewaytoairguns.org/GTA/index.php?topic=105520.msg1000343#msg1000343)
I think I posted a reference back to Bob's original SSG thread in one of my replies. I'm hoping it can be a place where people can share tips, tricks, settings, and parts help.
Blue