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Thread: MM fps on 400+ not lowering

  1. #1

    MM fps on 400+ not lowering

    so, my minimag... took it to the field to chrono it, and it dont want to go under 400+ FPS.

    Is it the regulator seat? you can see the shape of the valve and pin on it. Im ordering a O-ring replacement.

    is there anything im missing?

    thanks!

    (just shot my first x-valve today... fell in love )

  2. #2
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    Classic valve or X-valve?

    Was it leaking?

  3. #3
    Quote Originally Posted by Frizzle Fry View Post
    Classic valve or X-valve?

    Was it leaking?
    Classic MiniMag valve
    was leaking down the barrel, changed powertube O-ring and leak fixed.
    Last edited by Chencho; 05-26-2013 at 09:58 PM.

  4. #4
    Only the leak was fixed, still not going under 400fps. When I try the valve just doesn't pressurize

  5. #5
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    That is a pretty serious problem.. I would rebuild the entire regulator portion of the valve. New valve seat, valve pin, and spring pack. Also change the piston oring.

  6. #6
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    Do you have an aftermarket velocity adjuster on there?

  7. #7
    Everything stock, even spring in the powwetube.

    So, buy the whole oring kit +spring and pin?

  8. #8
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    Quote Originally Posted by Chencho View Post
    Everything stock, even spring in the powwetube.

    So, buy the whole oring kit +spring and pin?
    I would. Tell Tuna you need everything but the piston.

  9. #9
    Quote Originally Posted by BigEvil View Post
    I would. Tell Tuna you need everything but the piston.
    Alright, will update when I get it.

    If anyone else has more info I should know, plz post.

  10. #10
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    Quote Originally Posted by Chencho View Post
    Only the leak was fixed, still not going under 400fps. When I try the valve just doesn't pressurize
    If it doesn't pressurize, it is generally an indication of bolt stick. Since your mag is original with the powertube spring, I suspect you need to install a powertube spacer that is longer than the spring you are using now. If you know someone who has a mag with a level 10 bolt, get one or two of his shims and use one at a time to see if they help.

    A bad regulator seat oring will cause a high pressure in the front chamber which will result in a high velocity. Usually, the valve will vent air out the back when this happens.

    I would change all of the orings as a start anyway so that you know what you are working with. Most mag problems are due to a bad oring.
    Except for the Automag in front, its usually the man behind the equipment that counts.

  11. #11
    About finding someone with another mag... When i got to the field players were like "wow, where you got that?!" Lol

    I know someone with an xvalve, that's about it. Will change all the rings and eventually buy a slavery kit. I'm waiting to come back from the trip I'm going today to drop the money.

    Thanks for the reply :-)

  12. #12
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    What's up

  13. #13
    Sup splat, trying to get my lil one fixed to go back in the field!

  14. #14
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    Quote Originally Posted by athomas View Post
    If it doesn't pressurize, it is generally an indication of bolt stick.
    What are you guys seeing in "doesn't pressurize"? I don't see how it lacks pressure at 400 fps.

  15. #15
    When I turn the back screw counter clockwise to lower the fps it just "shuts down" it doesn't cock back.

  16. #16
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    Quote Originally Posted by Chencho View Post
    When I turn the back screw counter clockwise to lower the fps it just "shuts down" it doesn't cock back.
    Perhaps the spring pack is in upside down. The classic valve spring packs have a center post that runs into the pocket of the piston. If you put it in upside down, the adjuster nut just cranks on the post, making it on or off "regulation".

  17. #17
    I'll do that when I get back home and see, that may be it. Its something like on/off... Mmm...

  18. #18
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    Quote Originally Posted by Spider-TW View Post
    What are you guys seeing in "doesn't pressurize"? I don't see how it lacks pressure at 400 fps.
    In post number 4 it mentioned "When I try the valve just doesn't pressurize". I assumed that when he tried to fix one problem, he caused another.
    Last edited by athomas; 05-30-2013 at 07:13 PM. Reason: wrong person referenced

  19. #19
    Nah, the powertube leak was the PT o-ring.

    Now is that it doesn't regulate under 400fps and it does something like on/off like spyder wrote

  20. #20
    Quote Originally Posted by Spider-TW View Post
    Perhaps the spring pack is in upside down. The classic valve spring packs have a center post that runs into the pocket of the piston. If you put it in upside down, the adjuster nut just cranks on the post, making it on or off "regulation".
    Just got home, checked the pack and aparently that was it, trigger is light as it was and shoots quiet. Chrono tomorrow and will update. Just learning with every mistake :-)

  21. #21
    My baby is shooting.like a pro again!!

    Thanks to you all, idk what I would've done without AGD addicts :-)

    Thank you!!

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