28 inch barrel on ar ?

Discussion in 'Gunsmithing' started by timmyatnop, Nov 18, 2010.

  1. timmyatnop

    timmyatnop Well-Known Member

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    Ok here's what iam thinking proudly would not work very good but mabey it would.Ok dpms makes a 260 ar it doesn't have a very long barrel though,why couldn't a guy have an upper built in 260 with a longer barrel and shoot 140 gr burgers ,just thought it would be awsome ,oh just a thought would it have to be on an ar 10 lower,proubly so ? I wonder if any of these gunsmiths could build me one ,guess I would need the lower to .please chim in if you could build me one thanks .
     
  2. J E Custom

    J E Custom Well-Known Member

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    Yes a 260 can be built on an AR-10 lower and a longer barrel would be better.

    Something around 22 to 26" in a heavy contour.

    There are good rounds for the AR15 lower like the 243 wssm and the 25 wssm with
    24" heavy barrels, and the uppers are available from Midway.

    J E CUSTOM
     

  3. lazylabs

    lazylabs Well-Known Member

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    Just keep in mind that the long barrel is hanging off a rather thin piece of aluminum. It also has a fairly small barrel shank compared to most bolt guns so weight can become a factor. That said I have an 223 that is 26" 1.100 dia. and it shoots very well although the balance is so far foward it sucks off hand.
     
  4. timmyatnop

    timmyatnop Well-Known Member

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    That 260 is an awsome caliber,and if I could get it to 2800 or 2900 in an ar that would be my go to gun.iam gona check out midway to, that 243 wssm sounds awsome in an ar to thanks a lot.
     
  5. shortgrass

    shortgrass Well-Known Member

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    Gas porting changes with barrel length on 5.56mm/.223 Wilde ARs. Don't know about the AR10 series but it would seem logical. Follow the pressure curve.
     
  6. J E Custom

    J E Custom Well-Known Member

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    +1

    If you build it your self you need to buy one of the adjustable gas blocks so
    you can tune it for your load.

    J E CUSTOM
     
  7. msalm

    msalm Well-Known Member

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    Most AR10 long barrel variants are used in high-power type sports. 26" barrels are used, and mostly they go with an extended gas tube. The adjustable gas block isn't a bad idea, but if the builder starts smaller and function fires the rifle while opening up the gas port in the barrel you can do away with the adjustments. I've done that on about every new caliber I try, such as 17 Remington and 204 Rugers on the AR15 platform. Different length barrels and gas systems make a BIG difference on how large the gas port needs to be. I also read an article, I think on NJ highpower site that stated anything longer than 24 or it may have been 26" showed no velocity increase in the 260 Remington/6.5 Creedmore cartridges so you might want to just consider a 26" at the longest.