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Thread: Tuning and Spring Surgery

  1. #1
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    Tuning and Spring Surgery

    Please may I ask.....

    I have stripped and rebuilding a 0.22 BSA Superstar Carbine, being a bit harsh and boingy with its original spring I have completed the following:
    Discarded the original spring guide and turned a delrin replacement along with top hat.
    Using a Titan No.1 with 31 coils, I initially removed two coils, carefully lubricated, assembled and tested, running a bit hot.
    Removed another coil, ran hotter!
    Removed another coil (down to 27) still a bit hot, but, not consistent velocity. Maybe, could this be due to lubrication/grease pattern before settling? No detonation evident....
    Before committing further surgery on the spring, how many pellets should I put through it to stabilise lubrication/grease pattern if that is the cause.

    All be it, the harshness has gone, smooth cocking....

    I appreciate any help, or advise, and apologise if I am late in response to reply in kind.

    All the best to all....

  2. #2
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    Hsing-ee is offline may also be employed in conjunction with a drawn reciprocation dingle arm, to reduce sinusoidal repleneration
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    A whole tin (500) is a good idea, this gives the piston washer time to self-size, unless you have sized it too small in which case nothing is going to help.

    Lube should be a stripe of moly grease at the back of the piston and the merest smear on the piston seal, and use a small paintbrush to paint a smear on the spring (I get the kids paintbrushes from Tesco, a couple of quid for 6 or so).

    Good luck!

  3. #3
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    Many thanks Hsing-ee for your response...

    The piston seal was new from Chambers, no re-sizing, the fit seemed fine neither slack or tight, no different from my past dabblings.

    Moly was lightly applied with my finger tip to back of seal and slightly more to piston body and the spring lightly greased. I applied Moly-Gn to cylinder with a cotton swab and then wiped with another clean swab so that it was the lightest of coating.

    OK I'll put through pellets as recommended....
    All the best.

    P.S. Out of interest, anyone use a Titan No.1 in a Superstar and how many coils gave a good result?
    Last edited by SRV1; 18-07-2018 at 05:49 PM. Reason: Added P.S.

  4. #4
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    If still a little "hot" you'll really have to reduce the spring a little more. If you set it at no more than about 11.4 that should do it, as the power output is likely to rise as that new seal beds in. This will also have the benefit of even easier cocking, nicer firing cycle and even less strain on all components - linkages etc.
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  5. #5
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    I never lube the seal or cylinder, I apply a thin 5mm smear of moly on the front piston bearing and 10mm on the rear bearing; thin smear on spring ends, slip washers and top hat; shot variation is 0-10 fps! Jenny

  6. #6
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    Thank you TonyL and Jenny for your response....I'll push some pellets through during next week or so, see where it's at, and adjust as required.

    By the way, after cutting spring coils and compressing spring end, should one quench the end in water, oil or leave to cool naturally?

    All the best....

  7. #7
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    Quote Originally Posted by SRV1 View Post
    Thank you TonyL and Jenny for your response....I'll push some pellets through during next week or so, see where it's at, and adjust as required.

    By the way, after cutting spring coils and compressing spring end, should one quench the end in water, oil or leave to cool naturally?

    All the best....
    If seal fit is good as you say, I'd suggest the problem is excess lube.
    No need to lube an unsized seal and no reason to lube piston body. The only real area that may need lube is the rear bearing area (back 15mm or so). Any lube from seal or body of piston is likely being scraped forward by the piston seal and dieselling.
    Before you make any further alterations to the spring I'd have alook at the lube. My guess is that there will be lube on the face of the seal.

    If you do cut a spring, let it cool naturally.
    B.A.S.C. member

  8. #8
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    To quench or not ?

    After cutting and finishing a spring I used to leave to cool in the air which in effect anneals the wire which was
    red hot and softens it leaving it with no spring and I have had them snap .

    I now quench in oil once the spring has cooled well into a visual blue state so as to retain a full spring and
    not have a soft dead section .

  9. #9
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    Many thanks robs5230 and crowbar.....interesting conflicting comments regarding the spring....

    All the best to all....

  10. #10
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    There's no real conflict; so long as you don't quench from red heat and wait until the spring has gone dark, quenching will have little or no effect on the grain structure of the steel, and you'll be able to handle the spring a lot quicker if you haven't got to wait until it's cold.
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  11. #11
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    Quote Originally Posted by Rich View Post
    There's no real conflict; so long as you don't quench from red heat and wait until the spring has gone dark, quenching will have little or no effect on the grain structure of the steel, and you'll be able to handle the spring a lot quicker if you haven't got to wait until it's cold.
    I have to agree with Rich here. I've quenched from dark and now don't quench. Never had a spring break ever.
    Probably more issues arise from the finishing than the heating / cooling cycle.
    I must do 20 springers a year (at least) , all with multiple cuts and refinishes on the springs.
    B.A.S.C. member

  12. #12
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    Just an update for members who replied with suggestions....

    Eventually, testing after putting through 150/200 pellets through, it appears the grease/lubrication pattern have settled down. Nothing else done and is now a fairly consistent 11.11 to 11.46.....Thanks for your responses.

    All the best to all boingers.....

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