Upper receivers and accuracy?

Jmccracken1214

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  • Dec 10, 2018
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    Thomasville, NC
    I’ve got a grendel build, with a BA barrel, that shoots factory hornady 1.5-2” at 100. I’ve only tried this ammo on it, but have shot this ammo with numerous other Grendel’s and never got that bad of groups. I know this doesn’t mean anything without more testing, but it’s a cheaper end upper, PSA I think.
    Looking for an excuse to upgrade to a nicer receiver set. Looking at the aero m4e1.
    Any luck that it might tighten up groups?
     
    I would look more at the barrel than the upper if you don't think it is the ammo. I would try ammo first as some barrels like different ammo than others.
    I’m hoping it’s not the barrel, would be the first barrel from them that was this bad. I was curious maybe as to how the barrel is mated in the upper.

    Again, part of me is trying to justify a cooler receiver set than the palmetto
     
    I’m never going to try to talk anyone out of buying upgraded parts. A top tier upper will certainly get you smaller groups. But... You could also use this excuse to buy more tools. You could buy an AR accurizing kit to squeeze the last bit out of any upper
     
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    Gotcha. Remember, I’m not trying to dissuade you from buying better gun parts. Are you jonesing to buy gun parts or trying to chase smaller and smaller holes? If it’s just the latter you could also try a different cartridge, .224 Valkyrie is something that seems a tad more suited to smaller holes, further away
     
    Some people say that a standard forged upper allows more flex due to hand guard loading than a billet upper. And, uppers like the Aero M4E1 enhanced upper, where the hand guard is not attached directly to the barrel nut, are considered stronger than those that do. That said, I have a 6.5 grendel built on an Anderson Manufacturing upper that shoots very well with Hornady black (sub moa), and even better with my hand loads.

    You know how they say that in real estate investment it is Location, location, location? Well, my feeling is that it is the same for firearm accuracy, but it is Barrel, barrel, barrel.
     
    If your not really feeling the PSA upper, go ahead and upgrade it. I really like the Aero M4E1 receiver sets, the ones I've built on have had a good fit and finish. They seem to be a little more beefy too without adding too much weight.

    I would think that squaring the face of whatever upper your running will help more so than the actual upper itself. I've also found that new barrels sometimes take a while to settle in. There doesn't appear to be any rhyme or reason to it. Some shoot great from shot #1. Some shoot like hell until shot #251 then begin to settle in to good shooters.

    I think it has to do with the small inconsistencies in the rifling of any barrel. Some defects just take more time/rounds down the tube to smooth out. It's up to you decide when it's time to call it quits and try another barrel.

    My advice, give it another try. Also try some different ammo too. That should help rule out issues that aren't easily fixable, like a bad barrel/bore/upper/etc. I honestly don't pay much attention to how a barrel shoots until I have 5 boxes/100rds of factory ammo through it. Allows me to function test, zero scope, and get everything that's gonna come loose tightened and I'm confident everything is right with the build.
     
    I like BA barrels, or at least their 6.5creed barrels, but I had a 6.5grendel that didn’t perform and was sent back, the replacement was just as bad. I started noticing that the brass was growing over 12 thou on the first firing. Reloads that I prepped for that rifle bumping the shoulder back 3-4thou wouldn’t even chamber in several other grendels. The handloads produced much better results using the same charges/seating depth.

    I’d measure a fired case if you have one.
     
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    Well, my feeling is that it is the same for firearm accuracy, but it is Barrel, barrel, barrel.

    Once more, for emphasis.

    Krieger, Bartlein, etc. chambered by a good small shop, and THERE is where you’re gonna get the accuracy.

    I’ve yet to shoot a heavy billet upper, and yet I have handled, borrowed, and owned SEVERAL that were WELL under 1/2” guns.

    Gitcha a BCM if you need to spend some money real quick...but then call Wisconsin.
     
    Factory Hornady what? Frontier? Match? Hunting ammo?

    BA barrels were advertised to me as 2 MOA barrels from my local shop. I don't know if that's true.

    Are you shooting off a bipod with a rear bag? Known range? Quality optics mounted correctly?

    Is your barrel nut torqued exactly to spec?
     
    BA barrels were advertised to me as 2 MOA barrels from my local shop. I don't know if that's true.
    Sounds like they are trying to sell you something, or they think you’re the kind of guy they can spew their BS towards.

    They do carry a MOA guarantee, but there has been reports of QC dropping recently. I wouldn’t expect them to be 1/4moa barrels, but I am pissed if my BA 6.5creed goes over 3/4moa for multiple 5 shot groups.
     
    Sounds like they are trying to sell you something, or they think you’re the kind of guy they can spew their BS towards.

    They do carry a MOA guarantee, but there has been reports of QC dropping recently. I wouldn’t expect them to be 1/4moa barrels, but I am pissed if my BA 6.5creed goes over 3/4moa for multiple 5 shot groups.
    That could totally be, and *yes* they carry house engraved Shilen Match barrels, which I bought instead, and which was realistically a better fit for the gun when I was looking at their barrel choices. I see a lot of people enjoying the BA barrels so it could have been misleading. The same guy also advertised Form 1 SBR's as just needing to let the ATF know when you're leaving the State with it, rather than needing to ask permission in advance :) Sooooo I take what they say with a big grain of research if it's something I care about.
     
    You may try lapping the front face of the receiver and using Loctite to set the barrel. Or at least that would be where I started, try to make use of what you already have.
     
    @UpSideDown no worries. Shilen makes a good barrel. I’ve been happy with my two. I just have a certain level of apprehension anytime someone brings up something they heard from their LGS. My LGS has a guy that likes to talk about his DMR build and precision rifles that have 5.5lb triggers and shoot xm193 sub-moa consistently. I’m sure there’s more to the story, but I’m usually halfway to my car by the time he starts talking about ammo.
     
    I’ve got a grendel build, with a BA barrel, that shoots factory hornady 1.5-2” at 100. I’ve only tried this ammo on it, but have shot this ammo with numerous other Grendel’s and never got that bad of groups. I know this doesn’t mean anything without more testing, but it’s a cheaper end upper, PSA I think.
    Looking for an excuse to upgrade to a nicer receiver set. Looking at the aero m4e1.
    Any luck that it might tighten up groups?

    OP, I would not start buying shit until you test some other ammo. EVERY RIFLE is different, and every barrel is different. Just because two rifles shoot an ammo well doesn't mean the 3rd will. Correlation does not equal Causation.

    And I have multiple PSA uppers and they've all been fine. I would suggest:
    1.) try other ammo....match ammo
    2.) retorque barrel nut properly

    I have an 18" Lothar Walthar SPR barrel in my AR that consistenly shoots good reloads in the 1/2-3/4 MOA (5 shot) when I do my part. This same barrel shot my original plinking reloads around 2 MOA. This is a gun I KNOW can shoot very well for what it is, and it shot those plinking rounds horribly. The plinking rounds were Hornady 55gr FMJ-BT loaded on a Dillon 550 with H335. My Carbine AR shoots them better than that. Once I did load development, I got that to around 1-1.5 MOA with the same bullet and powder.

    Heres a pic of my varmint load of H335 and Nosler 50gr. bullets (2 groups) compared to the original Plinking loads. Keep in mind, with the Dillon Powder measure and H335, I can easily keep powder drops to within +/-0.1gr of powder. All seated on a Forster Micrometer Seater. Some combos barrels just don't like. don't start ripping apart your gun and spending money on shit you don't need yet.
    100yds, shot one after the other.
    IMG_3157.jpg
     
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    I like BA barrels, or at least their 6.5creed barrels, but I had a 6.5grendel that didn’t perform and was sent back, the replacement was just as bad. I started noticing that the brass was growing over 12 thou on the first firing. Reloads that I prepped for that rifle bumping the shoulder back 3-4thou wouldn’t even chamber in several other grendels. The handloads produced much better results using the same charges/seating depth.

    I’d measure a fired case if you have one.
    Fired, vs new... is about .006-.007 difference.
     
    I just built a precision AR on the seekins imrt upper as well. Very nice and solid.

    How is the barrel to upper reciever fit? Loose and sloppy? If so try loctiting the barrel into the upper and see if that makes a difference.
     
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    I just built a precision AR on the seekins imrt upper as well. Very nice and solid.

    How is the barrel to upper reciever fit? Loose and sloppy? If so try loctiting the barrel into the upper and see if that makes a difference.
    And cure it VERTICALLY, with the barrel DOWN.

    Don't be clamping up the receiver, much less clamping it sideways.
     
    I have gone so far as to cut shims to tighten the barrel upper receiver fit. Usually I have to freeze the barrel and heat the receiver to get it in. I also true and square the receiver. I have found that toward the higher torque spec the better.