G&P Sr-15 Feeding problem!

Discussion in 'Gun Building, Modifications & Repairs' started by KoVNinjaX3RO, Nov 5, 2012.

  1. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    Hey guys, so i looked almost everywhere to make sure there wasnt already a post on this, so mods please have have mercy lol! but anyways, so i just finished my m4 project (externally) and i had bought a G&P Sr-15 URX Body for it to replace my old g4-a5 body. From the start i had a vn m16 mid cap and a 20rd pmag and when i would stick em in the slot i noticed that the magwell is extremely large. I had to put 3 slits of electric tape on each side of the pmag with 2 in the front and 3 in the back, but only one on each side of the vn mag. I just received my 75rd emags, and samething, i had to put the 3 slits on each side, and the 2 infront and 3 in the back. And with all the mags, i noticed that they dont feed very well, i can hardly shoot my gun in semi cause the bb's will never feed, even when i have the mags completely loaded, and on auto, even when i just hold down the trigger for a few seconds, it seems like im shooting 3-4rd bursts and every now and then ill get a full 10-12 shots, notw i dont know if this is because the mag is loose, even though ive put 5 slits on the pmags, which pretty much takes a hammer to get em into the magwel, but even still they dont feed, ive taken them apart, stretched out the spring, lubed up the inside, and even put 5 or so bb's under the spring guide to give it more tension, but nothing. I look in the magwell and the hop seems to sit where its supposed to so i dont know what to do or what it could be, so if anyone has any suggestions of mods that theyve used that work when having the same problem, please let me know, im kinda mad that i threw 40$ (not alot but still) out the window for mags that dont even work right, or it could be the gun, but yeah please help me
     
  2. S0m3_0n3

    S0m3_0n3 New Member

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    take out the hop up unit and see if the mags feed into it directly, I have some dboys mags that wouldn't feed, found out the hop up feed tube wouldn't fit into the mag lip(no clue what it's called)
     

  3. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    And yes. Make sure the Feed tube of the hop chamber isn't damaged. And can feed mags outside the body

    If that isn't the case, check if your air nozzle is working properly. And is moving how it should.

    Might need to install a sector chip to allow bb's more time to feed. Depending on your internal set up.

    If none of that is the case, check the alignment of your hop unit. Make sure it's not moving around too freely with the gearbox installed.
    Use o-rings as a spacer around the barrel to push the hop unit against the gearbox. And se how that works. If the top stuff don't work.
     
  4. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    so i put in the mags again, and i noticed that i could move the magazine back and forth, so i put more slits of tape on the backside and forced the magazine forward, until it was sturdy enough for barely any wobble, and then i looked through the hop up lip and i noticed that the nozzle was working fine, but after each shot (on semi), when the nozzle would go back into place, the front of the nozzle was filling up about a 1/4 of the hole (look at pic below), is this fine or could this be the cause of the bb's not feeding correctly, and if so what could i do to fix it?
     

    Attached Files:

  5. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    That's normal lol. What brand nozzle are you using?

    You have any other spare hop units to try in your gun?
     
  6. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    Have you done any internal modifications with your m4? Just a thought
     
  7. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    no, i just bought a G&P Sr-15 URX Pro Kit, and i havent done anything internally to it, i just put the barrel, rails, and stock on and start shooting, and i just bought the hop up unti that i have in it, but the one i had before had the same problems, any ideas on what i could try?
     
  8. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    That's a hard one. Especially over a forum lol. Hmmmm.

    Do you know what's inside the gearbox? Straight up G&P?

    It would have really tight tolerances lol >.< haha rofl
     
  9. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
  10. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    do yall think that maybe i should just put an oring between the hop up unit and the gearbox, to force it forward and try that?
     
  11. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    You could try. Trial and error.


    It might be internally sadly.

    Is the hop chamber moving freely and not sitting up against the gearbox when assembled?
     
  12. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    oh not its tight against the gearbox, when i put in the upper receiver, the gb pushes against the hop up unit, and then i have to force it shut, so its pretty tight
     
  13. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    Lol. Ooo how I love challenge kits haha ;)


    Easy easy builds, especially G&P lol

    Something must not be right internally or externally lol. Outer barrel is fully tightened down right? (Sorry, I'm just double checking the externals being installed correctly so I don't need to keep it in as a factor in this lol)
     
  14. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    yes, im actually going to put the other hop unit again just try try it and see, but as far as i know everyting was assembled right, and the new hop up unit has a spring on it that is what causes it to push back against the gb
     
  15. Ehudakineyah

    Ehudakineyah New Member

    2,510
    0
    Mililani
    Try add an o-ring on the inner barrel itself. So it's in between the hop unit and the inner part of the outer barrel
     
  16. Archer627

    Archer627 New Member

    6,174
    5
    Figgington
    The glorious hop up o ring mod :). Get some really soft o rings I'd you do this. You may need two or three. Once they're on your barrel make sure your hop up slides freely inside the outer barrel (VERY IMPORTANT!). Then take the spring off the front of the hop up. Done ;).
     
  17. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    what would that do? i just put in the other hop up unit and samething, super tight against the gb
     
  18. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    Lol oh yes the glorious ;) when all else fails, use an o-ring xD bwahaha
     
  19. KoVNinjaX3RO

    KoVNinjaX3RO New Member

    69
    0
    Houston
    so i think i figured out what the problem might be, so i took the upper off and installed the hop up unit back to the gb and let it sit there freely, when i put in the mag i noticed that the hop up lip wasnt all the way into the mag, the mag was a bit loose and it wasnt pushing against the bb holder hard enough to set the bb's free (problem #1) but even with, the bb's still ejected into the unit, now after firing and seeing that no bb's were actually firing i took out the mag and left one bb in the hop up unit, i turned the gun upsided down, so that gravity would force the bb into the chamber, but when i fired (around 5 shots in semi, and about 10 in auto), nothing happened, the bb remained in the little tube of the hop up unit, so what im thinking is that, just like i drew on that pic that i inserted a few comments ago, i think that little part of the nozzle that is sticking into the path of the hole is blocking off the bb's from getting pushed into the chamber, and i took out the bb and watched the nozzle work, and i noticed that the nozzle doestn go back before it shoots, it just goes forward and back into place with the front end (about 1/4) sticking into the hole, now what could i do to fix that? put and oring behind the unit, forcing the hop up unit forward? and if so would that affect the flow of the nozzle, air, and whether or not the nozzle will still be able to push the bb into the bucking and shoot it properly?
     
  20. Ehudakineyah

    Ehudakineyah New Member

    2,510
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    Mililani
    It might mean its the wrong length nozzle. Sadly. The only way to check is to take apart the gearbox