Accuracy build

Discussion in 'Gun Building, Modifications & Repairs' started by ahood76, Oct 20, 2012.

  1. ahood76

    ahood76 New Member

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    I want build an m4 with a focus on accuracy. I really don't want to make it into any form of DMR. Just one real quick question. Are their any internal upgrades I can do, besides a TBB and a hop-up, that will boost accuracy?
     
  2. 703

    703 Active Member

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    Fix any compression issues you might have. Otherwise good hop-up and quality TBB barrel.
     

  3. ahood76

    ahood76 New Member

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    So new piston, cylinder and nozzle?? Sorry just getting into teching so I'm quite the noob
     
  4. wiseman

    wiseman New Member

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    Not necessarily new ones. But an air seal nozzle is necessary for good seal. To have a good compression, you have to prevent leaks from the cylinder to cylinder head by applying sealant or teflon tape. But sealant is much better.
    Use #14 oring on the piston head. Apply sealant on the TBB before inserting the bucking to prevent leak.
    Sanding (1-2 mm) the front of the tappet plate will help also by making good contact between the nozzle and hop up chamber, preventing leak.
    Apply also silicone oil inside the cylinder for the oring to glide smoothly.
    Ensure also that the GB is align with the HUPU for sealing purposes also
     
  5. ahood76

    ahood76 New Member

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    Wow Ahah well thank you very much! I appreciate it. Any specific kind of sealant? And what's the HUPU?
     
  6. Lefse

    Lefse Well-Known Member Supporting Member

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    Why has nobody mentioned barrel stabilizing? It doesn't matter if you have the best barrel and hop-up in the world if the inner barrel doesn't completely stable inside the outer barrel. The outer barrel needs to be stable too obviously.
     
  7. ahood76

    ahood76 New Member

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    How do you stabilize the barrel?
     
  8. Lefse

    Lefse Well-Known Member Supporting Member

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    You fill the gap between the outer and inner barrel with tape or grease or whatever works.
     
  9. Uller

    Uller Active Member

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    There are a few different ways of inner barrel stabilizing,so I will cover the two different ways ive gone about it that seem to work the best for me.

    The first method,and the messyest,is to slather a generous amount of petroleum grease on to the outside of the inner barrel,and install it into the outter.This method ensures that every amount of dead space between the inner and outter barrels is filled in,and makes the inner barrel quite rigid inside the outter barrel.

    The second method is to make wedges from thin plastic sheeting,and use these to stablize the inner barrel from its business end.Not as effective as the grease method,it is effective for short to medium range guns.The only downside to this method is creating shims that are of the exact same size,and reinstalling the sims each and every time the inner barrel is removed from the rifle.
     
  10. ahood76

    ahood76 New Member

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    Does the grease method have any downsides aside from being so messy? And do u ever have to change out the grease?
     
  11. 1badweasel

    1badweasel New Member

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    Santa Rosa
    I use thread seal tape and wrap it once or twice around the front and middle of the inner barrel.
     
  12. Uller

    Uller Active Member

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    None that in aware of,and no,changing out the grease is unnecessary
     
  13. Rocky

    Rocky New Member

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    Superior
    Well obviously you should re-grease though.
     
  14. ahood76

    ahood76 New Member

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    It just seems like the grease would clog up the inner barrel
     
  15. Lefse

    Lefse Well-Known Member Supporting Member

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    Then you have misunderstood the method of stabilizing the barrel with grease. The grease goes on the OUTSIDE of the innerbarrel.
     
  16. ahood76

    ahood76 New Member

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    No I understand it goes outside. But I'm thinking if there is some grease close to the end of the inner barrel it would get inside
     
  17. Uller

    Uller Active Member

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    Apparemtly I have to go into more detail with the procedure.Excess grease hast to be removed from the end of the barrel,and from the loading block.With the hopup turned off,insert a cleaning rod through the nozzle side of the hopup,and completely through the inner barrel to remove any grease that collects on the inside of the barrel.Regreasing isnt entirely necessary as quite alot of it stays inside the outter barrel.

    Then again if your one of those people who removes the inner barrel quite often maybe so,but not as much would be required as the initial barrel installation.
     
  18. Star_folder

    Star_folder New Member

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    Lexington
    I haven't had as much success with the grease method, it doesn't secure the barrel as much as the tape method does. The larger the outer barrel, the less effective this is. It does seem to work with high quality barrels, ones that just barely have enough room for the inner barrel.

    Compression consistency, Hop up quality, barrel quality, and bb quality. I don't think bb quality has been addressed. Now, as this is not a DMR, you don't need to use heavy .4s, which don't have the best quality. While nicer hop ups adjust for the low quality, the higher quality bbs will be more accurate, the difference is simply the range, the high quality bbs top out at .32g, and that's not heavy enough to really push your range.
     
  19. Rocky

    Rocky New Member

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    Superior
    Oh,Sorry guys just skimmed through the thread thought you meant greasing the gearbox :X.
     
  20. Uller

    Uller Active Member

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    The points you addressed are valid ones to be sure,and impact accuracy greatly.The guy who started this thread wanted to know about different ways to stabilize barrels,so I offered him some of the ways ive done it before in the past.Alot of the membership here do no research on there own,so going into a written oration on every aspect of accuracy is kind of dull.Esspecially if your someone who has done just that multiple times.So,I have resigned myself to be selective on thread topics,and answer questions when it amuses me.
     
    Last edited: Oct 23, 2012