Help me build a dmr!

Discussion in 'Gun Building, Modifications & Repairs' started by Napple, Nov 27, 2012.

  1. Napple

    Napple New Member

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    Hey everyone i want to build a dmr and need some help. I have a custom m16 with these internals so far:
    -ca piston
    -m140 spring
    -unknown gears that stand up to the 140 fine
    -metalball bearing spring guide
    -looking to get a matrix shock absorbent piston head
    -Metal hop up (going to r hop eventually)
    -Stock 6.08 barrell
     
    Last edited: Nov 28, 2012
  2. S0m3_0n3

    S0m3_0n3 New Member

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    Ok, what did you want help on? Did you remember to do all the DIY stuff?
     

  3. TheAirsoftTech

    TheAirsoftTech New Member

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    Seems pretty good, maybe get a nice torque motor. Like a Lonex A2 to help pull that spring a bit more efficiently.

    EDIT:
    We need a budget from you as well.
    I'd also get a better piston like a Lonex.
     
  4. Col1500

    Col1500 New Member

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    Replace the piston, CA pistons are really bad, just trust me on that one lol. I'd go for a Lonex or a ZCI. I much prefer full metal racks on pistons so I'd personally get a ZCI.

    I'd get an aluminum piston head and use sorbo with a Neopad to help absorb the shock. The extra weight on the piston head should be fine since you should only be shooting on semi.

    Radiusing the cylinder window would also help with shock. If you don't want to do that and you're really worried about cracking your gearbox (though you should be more then fine with just the sorbo) there's the Ajax STS, which transfers a lot of the energy to the receiver which has a lot more surface area that it can dissipate said energy with.
     
  5. Archer627

    Archer627 New Member

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    Im going to keep an eye on this thread. I'm guessing you guys can handle this. However, I need to chime in on something.

    The ZCI pistons are having problems being warped so be wary of that until they fix it.
     
    Last edited: Nov 28, 2012
  6. deathmechanic

    deathmechanic Active Member

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    If he is using a CA blue piston and he has lightened it, corrected AOE, glued the rack, they are pretty hard to beat. A Ajax STS for a M140 is a lil overkill. Sorbo and radiusing should handle most of the stress.
     
  7. Charkzilla20

    Charkzilla20 New Member

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    What shell are you using? Shell crackling can be a pain and expensive.
     
  8. Napple

    Napple New Member

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    Not sure on the shell. I picked up this gun secondhand from someone and just want to get a decent dmr out of it. I'll replace piston and motor. I was thinking of replacing the motor anyway. I might get a lonex but if not is an amp magnum motor at the same level? Also, any links to pistons that would be good?
     
  9. Urbanprodigy

    Urbanprodigy New Member

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    You're going to have to do a lot to the hop-up and a lot more tuning to the shell for it to be a DMR. I learned this myself when my build is now almost one month past when I had hoped to finish.
     
  10. Star_folder

    Star_folder New Member

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    The AMP will do, but it's not as good as a Lonex. Mostly, you need to replace the stock ferrite magnet motor with a neomagnet motor.

    Be wary of the Ajax STS, they are notorious for causing leaks between the gearbox and hop up chamber. I also agree with DM that it's overkill for this kind of set up. Sorbo and radius'd gearbox windows will be more than enough to handle any field legal set up.

    The shell should also be fine once it's been worked with like we've said.

    Don't forget your hop up assembly. Metal chamber is a good step, any one will do. Oh, and stay away from that piston head, they're poopoo.
     
  11. Southpawlegend

    Southpawlegend New Member

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    consider getting a 6.03 barrel when you replace the hop up.
     
  12. EDI1st

    EDI1st New Member

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    Fountain Valley
  13. Napple

    Napple New Member

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    Thanks EDI. Is there any specific piston head i should get? Im most likely going to get the lonex (a1 or a2?) motor. And i will get a 6.03 barrel.
     
  14. EDI1st

    EDI1st New Member

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    Eh, anything that works, I just uses POM piston heads.
    Don't use those "silent" type piston head/cylinder head
     
  15. Napple

    Napple New Member

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    Okay, and what spring would get me to 500-520 fps? Right now it's at 410 with an m140 spring which is why i need a piston head. My compression sucks. After a new piston head would an m150 do it?
     
  16. Lefse

    Lefse Well-Known Member Supporting Member

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    410 with an M140 spring, wtf?! Your compression assembly needs a serious overhaul, you should get at least 450fps with an M140. With good compression you'll get 500ish fps with an M150 spring. I love Lonex POM heads myself, they even come with an excellent o-ring.
     
  17. Star_folder

    Star_folder New Member

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    hmmm, I once had an SHS M160 chrono just under 400fps with .25s. I couldn't find a leak in the system, and it chronoed incredibly consistently. Sometimes springs are mislabled.
     
  18. Napple

    Napple New Member

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    Yeah i've been hearing about mislabeled springs alot more recently. But yeah this piston head is dead. It gives no compression and barely works. Therefore im looking into the prometheus pom. I'll look for a lonex though also.
     
    Last edited: Nov 28, 2012
  19. Lefse

    Lefse Well-Known Member Supporting Member

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    Why spend more than twice the money on a Prometheus head when a Lonex is at least as good? I would definitely get a Lonex head over a Prometheus one. Prometheus parts aren't bad, they are just ridiculously overpriced.
     
  20. Archer627

    Archer627 New Member

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    Element POM Piston heads are pretty good too (the orange ones). Actually, the ZCI POM piston heads look almost identical to them. I should buy one to compare.