Stuck on a build at barrel configuration

Discussion in 'AR-15 Discussion' started by Sgt_Skrb_25, Jul 25, 2012.

  1. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    AR gurus,

    Need some help figuring out the last stage of my build. I'm down to the barrel now. I'm leaning to a 18" mid gas 1:7 barrel. I want some range , at least 300 meters. Don't want a 20" , trying to build a shorter rifle. I understand all the characteristics of the gas,length, and twist rates. But stuck in picking the right configuration. Im80% complete. Got a JD Machines lower, Vltor
    Mur upper, DD auto bolt, H2 buffer, PSA LPK, Mega trigger, and all the bling . Please let me know what you guys think would be a good set up and why .
    Thank you
     

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  2. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Another look
     

    Attached Files:


  3. Quentin

    Quentin New Member

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    I think a 16" midlength would do fine at that range plus you said you wanted shorter. If 18" is a requirement then I'd go with rifle length gas for smoother operation and longer sight radius. Which barrel profile are you leaning to?
     
  4. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Not sure about profile yet. I guess what ever compliments the configuration best. What twist rate would be good for the 16"? I was going with a 13" rail regardless of barrel length to get decent sight radius.
     
  5. Quentin

    Quentin New Member

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    Well if you're going to be using 55 grain and up, 1/7" makes sense.
     
  6. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Materials & Construction
    Barrel Material: Chrome Moly Vanadium Steel
    Barrel Type: Cold Hammer Forged
    Barrel Caliber: 5.56 NATO
    Barrel Twist: 1:7
    Barrel Length: 16"
    Barrel Profile: M4 Profile
    Barrel Gas System: Mid-Length
    Inside Finish: Chrome Lined
    Outside Finish: Military Specification Heavy Phosphate Coated
    Muzzle Thread: 1/2" 28 TPI (Threads Per Inch)
    Gas Port Diameter: .750"
    Barrel Extension: A4
    Origin: Made in the USA
     
  7. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    I found a DD barrel with those specs for around $250 at Riflegear.con. They are local , might o check one out. Thanks for the help brother.
     
  8. powell0892

    powell0892 New Member

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    Sgt:

    Just curious have you had the chance to try out that trigger on another rifle or is this your first build? If so what were your impressions?
     
  9. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    That trigger is nice, you can adjust the creep out and the over travel and get around a 4.5-5 lbs pull. It's nice and crisp. The over all travel is so short now. Have never fired it but it feels netter than stock. Yes my first complete build, but modified other AR's.
     
  10. Quentin

    Quentin New Member

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    They mean gas block diameter, a gas port diameter that large would blow your eyebrows off! :eek:

    The port should be more like .063" for a 16" midlength
     
  11. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Quentin,

    I'll have to check into that. Thanks for the heads up.
     
  12. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Quentin,
    Thanks for the heads up, I'll check into that.
     
  13. Quentin

    Quentin New Member

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    You're welcome...


    You're welcome... :D
     
  14. AgentTikki

    AgentTikki New Member

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    LoL

    LoL


    Hey Sgt. Am I correct in assuming you are building a SPR/DMR ype build?

    If you planning on using it for a more precision oriented useage consider a 1/8 twist stainless or melonited barrel. 16 is just fine for 300 yards. If you plan on going out to 400+ id look into longer barrels.

    Also do yourself a favor and get a regular carbine buffer and a h buffer also. H2 might induce short cycling.

    If your planning on a 13" handguard I do think the magwel grip is a little redundant and just added dead weight. Personal opinion.
     
  15. Sgt_Skrb_25

    Sgt_Skrb_25 New Member

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    Agent Tikki,

    I'm still going back and forth, most likely a SPR, but wanted a little distance. I already got the carbine tube and have all 3 buffers on hand. I got the mag grip for s**ts and giggles. I originally wanted a 18" barrel. Still debating that. Thanks for the advice, appreciate everyone's input, I want to get this right with out buying stuff to replace my mistakes.