AR10 308 Loads

wapiti16b

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Mar 16, 2014
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What is the consensus on 308 loads for AR10s ?
I'd appreciate input for 16" barreled AR 10s.
Bullet weights & Brand
Powder burn rates & Brand
I'm loading for a friend that does 3 Gun but does not load centerfire rifle at this time.
Thanks!
 

Expert684

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  • Feb 22, 2013
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    I have one with an 18” barrel. Load is LC match brass, 210 M primer, 43.0 Varget, 175 SMK at mag lenght. Shoots 3/4” @ 200 yards. I am running a gas regulator on it.

    Second gun 24” no regulator, LC match brass, 210 M primer, 42.6 Varget, 175 SMK at mag lenght. Shoots 1 1/4” at 200.

    Brass is wet tumbled, annealed, sized, trimmed and primer pockets are uniformed in depth and flash hole deburred. Groups are 5-10 shots to confirm consistancy.

    Hope this helps!
     

    Howland

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    Sep 30, 2017
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    Bone stock Gen2 PA10 with 178 ELD-X, IMI Match brass and BR-2 showed bolt swipe at a very modest charge of 40 gr. H4895 and a similar charge of IMR 4064.

    I'm pretty sure it is simply overgassed as it rips the rim right off with CBC ammo. Other factory ammo in the 147-155 gr. range work fine until groups are measured. Nothing stellar.

    It has been relegated to the back of the safe pending an adjustable gas block. Another project has put this on hold.

    Whether buying or building, I'd recommend going with an adjustable gas block right out of the gate.
     

    Expert684

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  • Feb 22, 2013
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    Second on the gas block! The 18” gun got way more accurate after installation.
    Maybe less gas dumped behind the bullet before leaving the barrel?? I would have to had chono the loads before and after to see ES?
     

    GhostFace

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  • Apr 1, 2003
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    18 inch Armalite:

    178 HPBT (2.815 COAL)
    Hornady Case
    CCI LR primer
    42.7 4064
    2558 fps

    Submoa load

    1K yards is G2G
     

    Mtkrusmark

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    May 22, 2019
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    what are your guys thought on using imr 4064 instead of varget for shorter .308 barrels in gas guns? I use varget now but I'm looking for something a little faster out for my 16" 1:8 twist .308 stainless barrel in the dpms LR308
     

    Expert684

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  • Feb 22, 2013
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    4064 and Varget has almost the same burn rate. You might want H4895 or Accurate 2520. Port pressure might cause cycling problems, that is why in my previous post I mentioned an adjustable gas block.
     

    Expert684

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  • Feb 22, 2013
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    Maybe something as fast as IMR4198?? It is faster than H4895. I want to say I'm running 2450 out of a 18" LR308. 175SMK 43.0 Varget. Might be able to push a 168 a little faster? You might find something like a old D46 Lapua 170 grain match bullet. I got some, they have a rebated boattail and considerable less bearing surface. We used to use them in M1A Match rifles a long time ago. I shot a few D46's Sunday with 42.0 grains of H4895 out of a brand new 20" Ruger Precision Rifle to break in the barrel and it shot 3/4" group for 5 shots. I dialed up to 300 and cleaned the PRS steel rack down to I think a 3" plate. I had a little giggle when I left the range.
     

    woodlandshooter

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    Dec 7, 2013
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    Running 168 ELDs at 2610 from a 19" krieger 11.25 twist.

    LC or Federal Brass

    BR2 primers

    41.5 grains 8208 XBR
     

    PatMiles

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    Feb 25, 2017
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    I put together a 6.5 CM AR-10 for my 12 year old granddaughter last year so she could hunt with my son. First range trip it became obvious that an adjustable gas block was a must. Extractor was bending the groove, ejector was leaving beauty marks and the cartridge body had longitudinal scratches. Pulled an SLR off of an AR-15, put it on the AR-10, problem solved.
     
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    Ballistic RPh

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    Mar 1, 2019
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    LMT 308 with 16" barrel

    175gr SMK
    Federal brass
    CCI 200 large rifle primers
    44.7gr varget

    Consistently shooting 0.4 MOA at 100 yards. Haven't had a chance to shoot at longer ranges yet.