AR groups wandering. Most likely fix?

[Ura-Ki]

My Air Force Issue A2 HBAR would shoot a pretty consistent 4 inch at a hundred until it heated up, that had the standard contour barrel, nothing crazy!
My Current A2 607 replica matches that pretty easy, and with care and proper feeding, can usually cot that down to 2 1/2 to 3 1/2 inch groups!

 

[CLT65]

If you ever used an upper from White Oak Armament on a AR15 you would realize 1" groups come easy. Yes I have one.

Accuracy starts with a good barrel. Without a quality barrel (or lucking out on a cheap one), all the money spent on triggers and such won't do much good.

I'm not much into ARs, myself, but I put one together a few years ago, and went cheap. I don't remember what barrel I bought but as I recall it was about $120. I couldn't get it to shoot better than 1.5 moa at best, no matter what I tried. I bought a better barrel, but still couldn't afford to break the bank, spent under $200. I forget what I bought but it came with a MOA guarantee. I bought a nice trigger for it and a free float handguard. It's still a little frustrating because the best it will do is 1" @100, on a good day with good ammo.
Edit: I just looked, the barrel on it now is a Rainier Arms .223 Wylde Match barrel.

I expected better because I have an old Colt AR that I've had for 20 years. I had fiddled with it a lot back in the day, and once bought a paid of heavy barrels from Century, $99 for both. That rifle, with the cheap $50 barrel, will shoot 3/4" 100 yard groups consistently, and better on a good day.

 

[MrMillspecer]

These were shot from an AR15. WOA at 100 and 200 yards.


Just over 1/2" moa. 5 three shot groups on the same paper.

 

[watermerc]

I wondered if I was the only one who noticed that. They always claim to shoot 100 yard MOA groups, with cheap, off the shelf ARs and bulk FMJ ammo, but it's always with the magic words: "All day long" and "as long as I do my part".

Then there are all the internet commandos who claim to be able to shoot 1/4 moa on demand. If you can occasionally shoot a 1/4 moa group, congratulations! You're probably a great shot with a darn good rifle. If you can do it consistently, you don't need my congratulations. You already know you're a helluva shot, with an expensive rifle and a lot of practice! If you tell me you can do it "all day long" with your favorite dear rifle, and you're not a bench-rest competitor... Rrrright

Also I don't know about you but I physically and mentally tire out trying to shoot tight groups after a couple hours. Shooting unsupported is physically and mentally tiring. Or maybe I just a wuss.

 

[CLT65]

Also I don't know about you but I physically and mentally tire out trying to shoot tight groups after a couple hours. Shooting unsupported is physically and mentally tiring. Or maybe I just a wuss.

Unsupported, as in offhand? Dang, I usually can't do any better than 1/2 moa, offhand. Of course that's with a revolver. With a rifle I can do a little better.

 

[WillaminaOR]

Were those shot right in a row? What is the barrel contour? Could be walking the poi as barrel heats up. Factory upper? Who built it. Plenty uppers out there that will shoot sub 2" 10 shot groups or better.

10 shots, slowish aimed fire, but no intentional pauses. Barrel is a heavy profile but not super heavy. It looked like the group started on the lower left and finished up upper right. So it looked like it started pretty poorly and then tightened up as the barrel heated, which is why I was curious about possible issues and fixes. I was told the upper was bought from Keith's in Gresham about 10 years ago. It's a Black Hole Weaponry barrel, 5.56 chamber, 1:8, 20". I'm fairly sure the barrel will shoot but the rest of the upper looks like pretty generic parts. Maybe the receiver needs to be trued? Or maybe it's just an ammo problem, or shooter.

Bryan

 

[CLT65]

It sure sounds like something's not quite right there. If it wasn't for this quarantine thing, I'd offer to take a look at it. I'm not a gunsmith, but I've tinkered for many years and generally know what to look for. Right now though, we're holed up and avoiding people pretty carefully. My son just had surgery and is immune-compromised, so we definitely don't want the virus.

 

[osprey]

It may benefit from having the receiver squared and making sure barrel nut is torqued properly. Also my 1-8 twist barrels much prefer 60gr bullets and up over the lighter offerings.

 

[OldTengu]

I would consider putting some copper fouling remover through that barrel.

 

[ron]

I have worn out several WOA barrels shooting in matches over many years. WOA barrels consistently shoot around
1/2 inch 5 shot groups at 100 yards. This is with good match grade 77 SMK or 53 SMK reloads. Quality brass
also makes a difference. I find the Winchester brass almost half the group size as LC. Two ideas come to mind in your
accuracy issue. #1. J B bore paste smooth up and "Hand Lap" the barrel. #2- High temp loctite barrel to upper receiver.
Read about this years ago and decided to try out on an upper that I changed from an A2 to flat top receiver. It was a
worn barrel shot a little over one inch at 100 yards. After I loctite the barrel groups tightened up to about half that size.
I now loctite all my exspensive match barrels when I change barrels. Yes they can be removed. Last new barrel I
installed is a CLE chambered Krieger 20 inch service rifle barrel. Most exspensive barrel I have ever purchased.
Shoots one hole groups. Service Rifle Barrels: Krieger-SS

 

[WillaminaOR]

Well I knew I wanted to make changes to that upper and a perfect storm happened, I was left unsupervised in Salem and the shops actually had what I wanted in stock. I rebuilt the upper with an Aero M4E1 threaded, and an Atlas handguard.

Took the last 5 of those rounds out and put them on a target at 100Y. Results are a 2.17" 5 shot group. Not to shabby. Shooting prone out of the back of my truck, off bags, with a pretty good breeze.

I'll still plan on working up a handload.

Bryan

 

[CLT65]

Very nice improvement!

 

[WillaminaOR]

Very nice improvement!

Five shots compared to ten but yeah, good improvement. I used the same ballistic app on the first pictures. Second picture is of 5 shots out of my other rifle, also with a black hole barrel, same ammo.

 

[HB of CJ]

Answers already given. Grab the gun and see if you can see or feel any undue flex in the build. Does the upper and or barrel seem "loose". Ideally there should be very little or better zero determinable play. Closely inspect the muzzle crown for dings, nicks or errors. It does not take much.

Remove barrel. Square upper receiver front flat exactly. Do not remove much. Just square. Properly re torque the barrel to 40-42 adjusted pounds. Exactly center the gas tube to the barrel nut. Wedge or fit the upper to lower. Consider tome trigger tuning work. Check barrel straightness.

hundreds of builds. I found this all to be fun. Fuzzy memories.

 

[bfoosh006]

Here is some reasonably priced more consistently precise ammo. ( YMMV )

BOGO.. Australian Outback Ammunition, Buy One Get One Free 20 Round Box, .223 Rem 55GR, Sierra Blitzking UPC: 9332153001858-2

And WOA uppers have a great reputation for precision.

And make sure nothing is bonking the handguard.... gas block screws, MLok screws..etc.

And if anyone has a .308... this stuff was very darned accurate in my Large Frame AR's.. ( Read the various reviews )
Australian Outback Buy One Get One Free 20 Round Box .308 Win 165 Grain Sierra Gameking UPC: 9332153001049-BOGO

 

[bfoosh006]

I have worn out several WOA barrels shooting in matches over many years. WOA barrels consistently shoot around
1/2 inch 5 shot groups at 100 yards. This is with good match grade 77 SMK or 53 SMK reloads. Quality brass
also makes a difference. I find the Winchester brass almost half the group size as LC. Two ideas come to mind in your
accuracy issue. #1. J B bore paste smooth up and "Hand Lap" the barrel. #2- High temp loctite barrel to upper receiver.
Read about this years ago and decided to try out on an upper that I changed from an A2 to flat top receiver. It was a
worn barrel shot a little over one inch at 100 yards. After I loctite the barrel groups tightened up to about half that size.
I now loctite all my exspensive match barrels when I change barrels. Yes they can be removed. Last new barrel I
installed is a CLE chambered Krieger 20 inch service rifle barrel. Most exspensive barrel I have ever purchased.
Shoots one hole groups. Service Rifle Barrels: Krieger-SS
View attachment 698274

FWIW... I think you would appreciate using these VFG felt pellets. And I am a strong supporter of Kroil and JB Bore Bright Polish being used with the VFG pellets.

IMHO, don't bother ordering the smaller packs... go straight to the 500ct... I liked them that much.

Be sure to order the adapter as well...BROWNELLS VFG THREE PELLET ADAPTER | Brownells

VFG WEAPONS CARE SYSTEM PELLETS | Brownells

Using those products has produced admirable ( ? ) 10 shot groups for me.

And frankly, the pellets can be screwed on tighter fitting or looser fitting to the bore , so you can readily adjust the "snugness" to your desired fit.