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AR15 Accuracy issues

anginaprinzmetal

Sergeant of the Hide
Full Member
Minuteman
Jun 13, 2014
326
103
I put together an AR15 with different parts. Plan was to use it for gas matches PRS style, of which we have a couple a year locally. Distance out to 800 yds give or take.
I used a generic upper/handguard and lower that fit pretty well. Bolt/carrier is standard mil spec from PSA nothing special. Trigger Elftmann triggers single stage. BCM gas block. 20" Ballistic Advantage DMR barrel chambered 223 Wylde. As you can see didn't want to throw a lot of money at it since I'm a bolt rifle kinda guy.

Anyway, been shooting different types of ammo and this thing will shoot about 2 MOA. Good or bad ammo. My buddies' rifles shoot <1 MOA. Granted one is KAC and the other ones some mish mash of parts w/ Rainier arms barrel

Scope and based are properly torqued, tried with and without the muzzle brake but no difference. The rifle cycles fine with no problems, rifle length system.

Any ideas or am I SOL and should just get a new barrel ? I have had good luck with other BA barrels in 6.5 Cm that shoot sub MOA

Thanks
 
Have you tried a variety of ammunition?
If so what?
How many rounds though the barell?
 
sorry, barrel twist 1:8, ammo IMI match 77 grainers open tip and Norma match
 
Im just not familiar w/ ARs and not sure I want to sink a bunch of money without doing some research
 
sorry, barrel twist 1:8, ammo IMI match 77 grainers open tip and Norma match
I would bet your barrel would like 62gr SMK
224-Stabilization-1024x576.png
 
Try some different ammo.
55 gr 62 gr etc.etc.
What does it do at 100 yards?
Pics of a target might be somewhat helpful, especially to the people here.
 
Shot 55 but were absolutely shit. Can’t shoot the 62 grainers I have bc those are green tips and are banned in our range
Will try to post a pic though
Thx a lot
 
I put together an AR15 with different parts. Plan was to use it for gas matches PRS style, of which we have a couple a year locally. Distance out to 800 yds give or take.
I used a generic upper/handguard and lower that fit pretty well. Bolt/carrier is standard mil spec from PSA nothing special. Trigger Elftmann triggers single stage. BCM gas block. 20" Ballistic Advantage DMR barrel chambered 223 Wylde. As you can see didn't want to throw a lot of money at it since I'm a bolt rifle kinda guy.

Anyway, been shooting different types of ammo and this thing will shoot about 2 MOA. Good or bad ammo. My buddies' rifles shoot <1 MOA. Granted one is KAC and the other ones some mish mash of parts w/ Rainier arms barrel

Scope and based are properly torqued, tried with and without the muzzle brake but no difference. The rifle cycles fine with no problems, rifle length system.

Any ideas or am I SOL and should just get a new barrel ? I have had good luck with other BA barrels in 6.5 Cm that shoot sub MOA

Thanks

is the barrel free-float? If not, I would check to make sure that the hand guard is not getting hung up. Then I would move to pulling the barrel from the upper and make sure your squared. I have seen home builds shoot badly (me) because the nut was not tightened then backed off and then torque.
 
Yep, completely free floated, nothing touching the barrel. Barrel nut tightened to about 45 ft/pound. I'm starting to "read" (i.e. shop around, lol) for new barrels. I have the feeling this barrel will have to go back to BA.
White Oak Armory, Rainier Arms Ultramatch, Odin Works, Criterion from Compass Lake Engineering, Proof from Midway. All in 18-20", DMR style profile, rifle length. Any input will be appreciated.
 
Shot 55 but were absolutely shit. Can’t shoot the 62 grainers I have bc those are green tips and are banned in our range
Will try to post a pic though
Thx a lot

Don't waste your time with any FMJ ammo for accuracy testing. You're very unlikely to find 800 yard accuracy there, even with a great barrel.
To be fair I have seen a total of 1 example that shoots reasonably well at 600 yards (meaning consistent hits on a head-size or 8.5x11 plate) with FMJ - my 12.5" 6.5 Grendel with the Wolf 100gr FMJ ammo - but I consider that an anomaly that shoots way better than it should. The bullets are even smaller than the bore, for pete's sake. Anyway, that's the exception; the general rule is to expect the accuracy you're already getting, or worse, from FMJ ammo.

This sort of thing is a lot easier if you handload. If you're limited to factory ammo, try something (Black Hills, etc) with the 69gr SMK bullet, if it won't shoot that the barrel is probably just a bad one. I mean, it should shoot the 77gr SMK well too, but if you're already tried that with poor results, try the 69gr.

There would be other things to consider if you were getting 1-1.5 moa and wanted to improve it, but at 2+ moa I bet you've got a bad barrel. White Oak, Rainier Ultramatch, and Compass Lake are all good choices to consider IMO.
 
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How was the fit between you barrel extension to reciever? Did you play with the torque on the barrel nut? Sometimes this can help. I use a riser with regular rings for a scope, gives my head a good position, 20 moa, and is a rock solid mounting option. Sometimes that's better than a cantilever mounts. I built a 6.5 using a 24 inch BA barrel, and it shoots tits out. I did however use a Aero HP bolt.










I put together an AR15 with different parts. Plan was to use it for gas matches PRS style, of which we have a couple a year locally. Distance out to 800 yds give or take.
I used a generic upper/handguard and lower that fit pretty well. Bolt/carrier is standard mil spec from PSA nothing special. Trigger Elftmann triggers single stage. BCM gas block. 20" Ballistic Advantage DMR barrel chambered 223 Wylde. As you can see didn't want to throw a lot of money at it since I'm a bolt rifle kinda guy.

Anyway, been shooting different types of ammo and this thing will shoot about 2 MOA. Good or bad ammo. My buddies' rifles shoot <1 MOA. Granted one is KAC and the other ones some mish mash of parts w/ Rainier arms barrel

Scope and based are properly torqued, tried with and without the muzzle brake but no difference. The rifle cycles fine with no problems, rifle length system.

Any ideas or am I SOL and should just get a new barrel ? I have had good luck with other BA barrels in 6.5 Cm that shoot sub MOA

Thanks
 
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Barrel & Ammo are like Man & Wife...if it ain't a great match?...it doesn't matter how high end the vehicles or how big the mansion or how fat the bank account...things aren't going to work out and that includes bullet weight, shape and build and powder weight and burn rate which means you could try many bad combinations before you find the close to ideal one and one other thing that caught my attention is you stated only 150rds shot whi9ch to me means that the newly built arm isn't even seated/broken in yet and there's going to be variance until the components are...BCG's and even Buffer Systems need to cycle a bit until they get settled in to their new homes and a film of carbon needs to establish itself in the nether regions of the operating system before true cycling consistency enters the mix and I know what you're thinking right now and true...some auto rifles shoot lights out from right out of the box but they are the exception and not the rule and a great reason to buy a lottery ticket that day. LOL!

I'd run at least 500rds (preferably 1,000) through a .223/5.56 auto before sitting down with about 1/2 dozen different loads to begin grouping analytics and/or proclaiming any judgements regarding the auto rifle...just a suggestion. ;)
 
The imi 77gr just shoots ok in my experience. Haven't tried the norma match, but the stuff I have is the same 77gr Sierra bullet as the imi. Maybe your gun just doesn't like that bullet. I have put together several guns with BA barrels, and they have all shot well. For the money, they are hard barrels to beat.
 
Like others have said-try better ammo (FGMM, Black Hills etc) and maybe have your buddy shoot your rig-if he's more of a gasser guy vs. bolt like you.
 
There are 100 things that can affect accuracy on an AR. And it also takes good fundamentals to shot one well. The target looks a little suspicious with the thrown shots. How close to the handguard is your gas block? Are you 100% sure the scope and mount are good? What’s the scope and mount and is it mounted on the receiver only or partially on the handguard?
 
There are 100 things that can affect accuracy on an AR. And it also takes good fundamentals to shot one well. The target looks a little suspicious with the thrown shots. How close to the handguard is your gas block? Are you 100% sure the scope and mount are good? What’s the scope and mount and is it mounted on the receiver only or partially on the handguard?

This!

can you post up some photos of the rifle? Specifically the optics mount/upper receiver and the gas block (looking down the handguard)

Have you shot your buddies rifles that are shooting well? Same groups as theirs? Have they shot yours?

As others have said, upgrade your ammo and test, as well. 1 box of FGMM 69 and 77 grain will show us more.
 
I went the same route as you on your build, inexpensive upper/lower/bcg then got a nice free float carbon fiber handguard and a Green Mountain 18" fluted match wylde 1/8 twist rifle length gas, 3lb drop in trigger,nikon 3-9. Trued the upper and bedded the extension. Took it out on the bench with match ammo in 55,62,77 and none would shoot better than 1.5 m.o.a.and most at a LOT more than that. So off to the reloading bench doing the O.C.W. and seating depth, now my 50gr varmint grenades are shooting .65 moa.
guess what i'm saying is dont give up on your gun,it might be ammo.
 
This!

can you post up some photos of the rifle? Specifically the optics mount/upper receiver and the gas block (looking down the handguard)

Have you shot your buddies rifles that are shooting well? Same groups as theirs? Have they shot yours?

As others have said, upgrade your ammo and test, as well. 1 box of FGMM 69 and 77 grain will show us more.
This. ^. All of it.

I would try some Hornady ammo also.
 
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I have had good luck with 35-40 ft/lbs on the TQ for the barrel nut...with a barrel nut design like a Geissele.

Second thing...IMI 77gr has been inconsistent for me at least...

Third thing...what handguard did you go with? what kind of barrel nut does it have? Reason I ask...is you can load an AR15 pretty heavy and effect the fulcrum at the barrel extension without a stable barrel nut design (one of the reasons I like POF's design)...there is a reason why the MK12 has the handguard it has...
 
A couple things:

- The IMI ammo in any rifle I shot it in (both 55 and the 77 Razor) never shot particulary well. It's good ammo with high velocity but accuracy wise it was always meh. I use a lot of IMI in carbines, but thats a totally different type of shooting that this ammo is great for.

- I have a Ballistics Advantage barrel in my oldest Stag carbine from like 2001 that is on its 6th or 7th barrel. Noticed zero improvment/difference over whatever the barrels Stag uses and replaces shot out barrels with. Contacted BA about their MOA guarantee warranty and if your ammo isn't on their short list of 'approved ammo' it doesn't count. I think its more of a gimmick than anything.

- Remember that even the Mk12 with a Douglas barrel only has an accuracy requirement of 1.5 MOA. Some rounds do better and some barrels just don't get under 1MOA no matter what you do. I started down that road years ago with the HCS upper and Black Hills 262 where I couldn't get less than 1 MOA on a group regardless of anything. The good news was, it was always right around 1 MOA every time. After messing around with reloading for it, found a few different loads where I'm shooting .7 constantly at still 2750+ FPS. But if I shoot Mk262, its back to a hard ceiling of 1+ MOA.

- Are your groups shot at 100 yards that you took a picture of? If so, when you fire the gun, is your reticle above the target after pulling the trigger? Your verticle spread in the groups is too great for it to be a velocity issue on the round at that range; I'm betting the recoil is bringing the front end up and moving the stock position down a bit due to it not being perfectly set on your collar/shoulder as well as the rear bag giving in. This is very common with precision ARs. Play around with where on your collarbone/shoulder the stock is, get a good amount of bag under it, but focus on keeping it pulled relatively tight with your shooting hand, rearwards and I bet you'll see your reticle settle very closely to your original POA and cut down on that verticle spread.
 
Have you dry fired from the position the groups were shot? Does the reticle move on target when dry firing?
 
I'd run at least 500rds (preferably 1,000) through a .223/5.56 auto before sitting down with about 1/2 dozen different loads to begin grouping analytics and/or proclaiming any judgements regarding the auto rifle...just a suggestion. ;)

That is completely unnecessary, and doesn't have anything to do with reality.
 
So fill me in gents...during which decade did folks decide that semi-auto actions of any sort no longer need to go through a break-in period of auto cycling before getting serious about consistent accuracy results?...because it sure is a reality for me and every new auto firearm I've shot in.
 
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So fill me in gents...during which decade did folks decide that semi-auto actions of any sort no longer need to go through a break-in period of auto cycling before getting serious about consistent accuracy results?...because it sure is a reality for me and every new auto firearm I've shot in.
Break in for accuracy with a quality barrel is a myth.
Rough finished barrels may need a few rounds to smooth them out.

Break in for reliable cycling isn’t a thing anymore either with quality manufactured and designed firearms.

It’s not 1917 or 1979 anymore
 
So fill me in gents...during which decade did folks decide that semi-auto actions of any sort no longer need to go through a break-in period of auto cycling before getting serious about consistent accuracy results?...because it sure is a reality for me and every new auto firearm I've shot in.

About when modern manufacturing took place...unless specifically spelled out in the manual...break-in is not required anymore...

In the last 10 years...none of the firearms I bought required a break-in...
 
Break in for accuracy with a quality barrel is a myth.
Rough finished barrels may need a few rounds to smooth them out.

Break in for reliable cycling isn’t a thing anymore either with quality manufactured and designed firearms.

It’s not 1917 or 1979 anymore


Wow...seems I'm personally encountering a very different mentality here at the Hide...7 lugs rotating in and out...Buffers sliding in and out...hammer getting cocked...bolts rotating....and no break-in required huh?

I hafta admit that it's been awhile for me...outside of this DPMS LR-308 AP4 I recently acquired?...my last AR platform came in the form a of Colt NM H-Bar (back in the mid-90's) that I used in IPSC competitions and I even watched that fine firearm exhibit group shrinkage as round count increased and SD decreased as it got shot-in and broke-in but in the name of keeping an open mind?...I'll just go along to get along here I guess.
 

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About when modern manufacturing took place...unless specifically spelled out in the manual...break-in is not required anymore...

In the last 10 years...none of the firearms I bought required a break-in...

Thanks for being civil bringing me up to snuff here...I'm beginning to see the problem...it seems my past experiences are antiquated. :(
 
Some manufacturers build things to diff specs...however your most high quality firearm makers in the AR realm or modern sporting rifle arena do not required any break-in unless specified.

You have tremendous improvement in CNC as well as the introduction to EDM...as well as different coatings...

It is like new cars...all engines now are factory broke in before leaving the factory (some still require a break-in period to make sure tolerances go in-spec)...but simply put...break-ins aren't a thing much...unless specified...like a Les Bear...

Truthfully, unless it is a custom gun like a Les Bear...if a manufacturer requires a break-in its because they can't keep tolerances to spec...mostly due to sourcing out casting/MIM parts to India or Asia...so a break-in is specified so that tolerances line up...but its not because of improving barrel accuracy...
 
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So fill me in gents...during which decade did folks decide that semi-auto actions of any sort no longer need to go through a break-in period of auto cycling before getting serious about consistent accuracy results?...because it sure is a reality for me and every new auto firearm I've shot in.

Sounds to me like you're evaluating the whole rifle as a system-500-1000 rds of functionality testing to make sure everything works well-which has some merit. Like in the Military when I was handed an M16a1 that already had 1000s and 1000s of rounds through it and it ran like a swiss watch. It was "combat" accurate I guess-I could hit crazy Ivan's at 300m with regularity using iron sights. Barrels-especially good ones-in my experience don't need any break-in beyond a few rounds-in my experience to showcase how accurate they will be.
 
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Sounds to me like you're evaluating the whole rifle as a system-500-1000 rds of functionality testing to make sure everything works well-which has some merit. Like in the Military when I was handed an M16a1 that already had 1000s and 1000s of rounds through it and it ran like a swiss watch. It was "combat" accurate I guess-I could hit crazy Ivan's at 300m with regularity using iron sights. Barrels-especially good ones-in my experience don't need any break-in beyond a few rounds-in my experience to showcase how accurate they will be.

Correct...I would never imply that "Barrels" are in need of any break-in...(however I am the old school sort who compound/laps new button cut barrels smooth before wringing them out)...but all the nating/moving parts in a newly assembled action?...well?...maybe if you're paying top dollar to a pro smith I can see where an extensive break-in (like I referenced) probably would be necessary but let me take a moment to refresh the minds of those grilling me here about that methodology that's purportedly been reduced to "Myth" status by reminding you folks of the first sentence in the OP here of...

"I put together an AR15 with different parts."

are you all starting to pick up what I'm laying down here now?.....or are you all still figuring me to be an out of touch with reality idiot that needs a grilling? LOL! ;)
 
I assemble all of my AR’s with parts. I’d never shoot several hundred rounds before working up a load. If I’m not getting 3/4moa groups or better by 100rds when there’s no known cause, I’m selling that barrel or giving it to a friend.

@JINKSTER , what are your precision requirements for an AR? Sub half moa? Sub .25moa?
 
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I assemble all of my AR’s with parts. I’d never shoot several hundred rounds before working up a load. If I’m not getting 3/4moa groups or better by 100rds when there’s no known cause, I’m selling that barrel or giving it to a friend.

@JINKSTER , what are your precision requirements for an AR? Sub half moa? Sub .25moa?

That certainly is a very loosely posed question that would require me to ask a number of questions for purposes of definition to give you any sort of eductaed answer...questions like what sort of AR are we talking about?...16" Carbine or 24" LR?..,and what chambering?...suppressed?...scope?....but really?...I didn't post in this thread to challenge, argue or debate the methods, regimens or ideologies of others...I only offered the OP "a suggestion" in an effort to be of some help...which apparently went against the grain of most here for some reason.
 
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I assemble all of my AR’s with parts. I’d never shoot several hundred rounds before working up a load. If I’m not getting 3/4moa groups or better by 100rds when there’s no known cause, I’m selling that barrel or giving it to a friend.

This right here. You can spend a lot of time and money trying to get an AR to shoot sub MOA. I have no interest in a rifle that only shoots one magical load decently. A good barrel should shoot multiple loads well.

My thoughts are, try some 69 Sierra MatchKings. These should should well from just about anything. A heavier 77 grain bullet could have issues in a 1:8 twist barrel, so don't try to go too heavy.

I have a 26" White Oak barrel on my AR. I have shot it in a PRS match. I never got satisfactory accuracy from it. Some research indicated it may have been the varmint chamber my barrel has, which people said shot 52 grain bullets great, but not heavier stuff. It was about 1.25 to 1.5 MOA with a 69 SMK.

If you are going to use this for a PRS gun, and regularly shoot beyond 600 yards, and considering purchasing a new barrel ( a lot of "ifs" I realize) perhaps looking into a 224 valkyrie barrel would be a better next step? This will eventually be the fate of my AR as well.

Long story short, don't waste a lot of time and money on a barrel which isn't shooting to your expectations.
 
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Wow...seems I'm personally encountering a very different mentality here at the Hide...7 lugs rotating in and out...Buffers sliding in and out...hammer getting cocked...bolts rotating....and no break-in required huh?

I hafta admit that it's been awhile for me...outside of this DPMS LR-308 AP4 I recently acquired?...my last AR platform came in the form a of Colt NM H-Bar (back in the mid-90's) that I used in IPSC competitions and I even watched that fine firearm exhibit group shrinkage as round count increased and SD decreased as it got shot-in and broke-in but in the name of keeping an open mind?...I'll just go along to get along here I guess.

All barrels are subject to copper fouling. I would say that’s the extent of breaking in thats necessary, if, you consider that a break in process. However, when people are talking about initial breaking in, they do the whole shoot clean shoot clean...

I’ve probably done almost all the “recommended break-in’s” and I’ve never seen any advantage as oppose to if I did not clean, shoot Initially.
 
I assemble all of my AR’s with parts. I’d never shoot several hundred rounds before working up a load. If I’m not getting 3/4moa groups or better by 100rds when there’s no known cause, I’m selling that barrel or giving it to a friend.

@JINKSTER , what are your precision requirements for an AR? Sub half moa? Sub .25moa?
Behold my AR15 that I assembled WITHOUT parts.
115498331-ar-15-rifle-white-silhouette-on-a-black-background.jpg
 
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That certainly is a very loosely posed question that would require me to ask a number of questions for purposes of definition to give you any sort of eductaed answer...questions like what sort of AR are we talking about?...16" Carbine or 24" LR?..,and what chambering?...suppressed?...scope?....

It’s not really a loose question at all, but I was focused on precision AR’s. If you have different requirements for different AR’s, I’d be interested in what they are.

I’m just trying to understand the whole 500-1000rds to get a 223/5.56 AR to shoot as good as it can. You’ve defended this statement several times, so I’m trying to understand what your goals are. You may be light years ahead from what most people are looking for.
 
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It’s not really a loose question at all, but I was focused on precision AR’s. If you have different requirements for different AR’s, I’d be interested in what they are.

I’m just trying to understand the whole 500-1000rds to get a 223/5.56 AR to shoot as good as it can. You’ve defended this statement several times, so I’m trying to understand what your goals are. You may be light years ahead from what most people are looking for.

Okay...I detect some level of sincerity in your inquiry so?...I'll play the middle ground and call it a 20"er in which case I'd expect 1/2-3/4 moa out of a tight yet smooth running .223/5.56 and 1-1 1/2 moa out of something towards the 7.62/.308 end of the spectrum nut now to humor me?...let's take a look at just a microcosm of what goes on in an AR platform "Action" by taking a look at just "A New Entry Level Rifles Trigger"...where if instead of wasting ammo you just remove the upper and begin finger cocking the hammer and cycling the trigger a couple hundred times you can feel it improve as the mating surfaces wear into each other where the new trigger that felt gritty and sticky actually begins to feel quite a bit slicker and crisper...and that's just the trigger...now do the same with the 7 lug bolt that's rotating as it moves fore & aft in a carrier that's cocking that hammer along with cycling a buffer system and establishing what previously was a non-existent film of carbon sealing things up in the gas system as that new AR begins to run smoother and more consistent as the round count increases and BTW?...I'm not light years ahead of anyone and I'm certain there's a lot of very experienced and knowledgeable folks here that could teach me a thing or three.
 
Given the Ballistic Advantage barrel, the round count, and the ammo used.... I wouldn't expect incredible groups.
The barrel may fire better groups after a good break-in... but IMHO, you could also spend as much money on ammo trying to make that barrel shoot to your expectations... as you would on a better quality barrel.
 
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Given the Ballistic Advantage barrel, the round count, and the ammo used.... I wouldn't expect incredible groups.
The barrel may fire better groups after a good break-in... but IMHO, you could also spend as much money on ammo trying to make that barrel shoot to your expectations... as you would on a better quality barrel.
IMO the pictured groups are showing something mechanically wrong. Gas block touching handguard, something shifting in the scope or mount, barrel nut/extension not seated/torqued properly, etc...

I’m seeing somewhat decent groups with bad flyers. That would lead me to believe that it’s not just a barrel that won’t shoot. I bought a BA barrel for our large frame because the price was so good I couldn’t not buy it- it’s a laser. That doesn’t mean all of them will shoot but the inter webs will lead some to believe that if it’s not a $600 cut rifled barrel it won’t shoot. That’s definitely not the case.
 
First group I shot out of my buddy’s AR that has a Rainier barrel was just around 1 MOA, may b less. Same ammo. Didn’t bother to measure bc it was painfully obvious there was something wrong with my rifle. He shot mine and got the same shitty results, and this guy is not a noob. He has shot the NRL and PRS finales several times and he had the same crappy groups.
There’s some play between the upper and lower but it’s not bad, not sure if this would be the issue. Have put a wedge in but no difference even when play is much better. No obvious mechanical issue otherwise. Nothing touches as best as we can tell, nothing flexes, torque are ok.
Recoil out of this rifle is more than I would expect, feels like a carbine length system, sort of speak. We were wondering if the gas port was too big. Having said that I’m use to recoil, train w a bolt 308 sometimes, so that I don’t think this is the issue.
Anyways went ahead and ordered another barrel from WOA. We’ll see if this woks.
 
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Yep, completely free floated, nothing touching the barrel. Barrel nut tightened to about 45 ft/pound. I'm starting to "read" (i.e. shop around, lol) for new barrels. I have the feeling this barrel will have to go back to BA.
White Oak Armory, Rainier Arms Ultramatch, Odin Works, Criterion from Compass Lake Engineering, Proof from Midway. All in 18-20", DMR style profile, rifle length. Any input will be appreciated.

call BA and ask them if hand lapping the barrel would void the warranty. Also, are you sure that the upper receiver is in spec, the threads are cut properly and the extension sits square before the nut is torqued? who manufactured the upper receiver?

There are a lot of good suggestions being laid out, just tear it down and restart the assembly process over again. It would be the cheapest option and BA will probably ask the same trouble shooting questions.