G&G CM16 Raider Barrel Replacement

Discussion in 'Gun Building, Modifications & Repairs' started by Spagooti, Oct 21, 2021.

  1. Spagooti

    Spagooti New Member

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    Boston
    I bought a 5ku 2 piece outer barrel for my cm16 raider, and when installing it i found out that what i think is called the barrel nut has too small of a hole for the barrel to go through. it cant fit around the wider parts of the barrel, even when i take the 2 parts of the barrel apart, so i cant lock the barrel to the receiver. i could try using a dremel to widen the hole, but I've never used one before and id rather just buy a new piece. i don't know anything about the mounting hardware for barrels and hanguards
     
  2. Guges Mk3

    Guges Mk3 Administrator Staff Member Administrator Supporting Member Lifetime Supporter

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    G&G Outer barrels don't play nice with other parts. In fact G&G is least supported in structural parts by other makers.

    Is your 5KU OB specifically made for G&G. I have not seen G&G Spec items made by 5KU
     

  3. Spagooti

    Spagooti New Member

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    Boston
    no, it isn't. i didn't know i should've been looking for G&G spec barrels
     
  4. aotsukisho

    aotsukisho Well-Known Member

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    G&G has a TM-compatible upper receiver but their outer barrel is a bizarre 3-piece (at least) with a narrow diameter barrel nut that fits over it. Even the ARP9 with its one-piece barrel uses a narrower than usual nut.

    Just get a Marui-compatible barrel nut. Any aftermarket rail system should come with one, you will not be able to adapt the G&G RIS onto any other brand outer barrel.

    [​IMG]
    Modern CM16 with DD rail

    [​IMG]
    ARP9 with aliexpress M-lok rail

    [​IMG]
    Older GR16 with I believe a JG outer barrel with almost everything else from a TM NGRS

    tl;dr - G&G spec outer barrel, G&G spec nut, TM compatible upper receiver
     
  5. Spagooti

    Spagooti New Member

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    Boston
    so i should get a new handguard for the barrel to work? i was planning on getting an 86068 product # on evike. do you think this would work fine? thanks for the help
     
  6. aotsukisho

    aotsukisho Well-Known Member

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    442
    It should fit, that handguard comes with a barrel nut so you'd be set.

    That being said, sometimes when mix matching brands there might be slight differences in top rail height on the rail and receiver, and sometimes there is a small gap between the rail and the receiver if the mounting mechanism isn't adjustable (like the Ares).
     
  7. Spagooti

    Spagooti New Member

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    Boston
    thanks, I'm not too worried about the rail having a gap or being raised at all. but say i didn't want to replace the handguard, could something like 17226 work? my friend has an arp9 and wants a longer barrel.
     
  8. aotsukisho

    aotsukisho Well-Known Member

    797
    442
    That's a barrel nut specifically for the M4A1 style delta ring RIS (like the one on my GR16). If he wants to add a longer inner barrel but keep the G&G rail, it's a lot easier to use a fake suppressor to add length to hide it.

    Actually, looking at the listing reminded me to recommend it's a good idea to also get barrel shims, sometimes they are necessary to prevent wobble or to properly space the barrel nut for handguard mounting when mix matching brands.

    Make sure he's aware that the FPS increases quickly if he does so, I know firsthand that a 409mm inner barrel will give >420fps