Anyone got hands on experience with 16" 308 accuracy? - Page 1

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[ARCHIVED THREAD] - Anyone got hands on experience with 16" 308 accuracy?

Posted: 1/13/2021 1:31:26 AM EDT

I purchased a Knights EMC clone build from a member while back. 16" Noveske barrel and I threw a Trijicon 1-8X on it.

Cannot get this gun to shoot better than 2 MOA and that's rare. Typically 2.5 MOA to 3 MOA. Started with some surplus ammo and moved to handloads. Using Hornady 150 gr SST's, LC brass, Winchester primers, Varget powder.

I've got several rounds loaded up to take it out and perform the OCW test on it when weather permits.

Just wondering if maybe a 16" barrel isn't enough to stabilize the rounds and be a ~1 MOA gun and I'm beating my head against the wall trying to get it to be.

Posted: 1/13/2021 1:39:00 AM EDT

[#1]

There are a lot of variables there...

I'd try a tried and true accurate load first... some 168 GMM.. and see what it can do.

A good rifle with a good shooter (no offense) shooting a load that it likes, should still be capable of 1-2 MOA with a 16" barrel.

Posted: 1/13/2021 1:56:58 AM EDT

[#2]

Quote History

Quoted:
There are a lot of variables there...

I'd try a tried and true accurate load first... some 168 GMM.. and see what it can do.

A good rifle with a good shooter (no offense) shooting a load that it likes, should still be capable of 1-2 MOA with a 16" barrel.

View Quote

I do need to get my hands on some really good know-to-be-accurate factory ammo I guess and try that too.

I'm a 1.25 MOA shooter. Meaning I consistently average about 1.25 MOA accuracy.

Posted: 1/13/2021 2:11:50 AM EDT

[#3]

Light large frames are just about the hardest gun there is to shoot well.

Barrel length has almost nothing to do with accuracy, especially in this context.

Posted: 1/13/2021 2:25:44 AM EDT

[#4]

What ever the problem might be... it's not because of a 16" barrel.

I have multiple 16" .308 gas guns that shoot MOA, sometimes under.

Posted: 1/13/2021 3:00:49 AM EDT

[#5]

You should verify barrel nut torque, muzzle device torque.
You need a baseline with FGMM after cleaning the barrel. Try 168 and 175 grain, your barrel will prefer one of these.
But, do you know anything about the barrel history? The barrel may just be a bad shooter, maybe that is why it was sold.
You may achieve better accuracy with a different muzzle device on that particular barrel
FCG?
As said above, a lot of variables.

Posted: 1/13/2021 3:17:46 AM EDT

[#6]

Quote History

Quoted:
Light large frames are just about the hardest gun there is to shoot well.

Barrel length has almost nothing to do with accuracy, especially in this context.

View Quote

This. My 16” .308 AR build with a Criterion chrome lined CMV barrel hovers around 1 MOA 5 shot groups with M118LR (typically around 1.1-1.2) if I do my part.

Many other things could be at play here and I’d suggest testing out a number of different loads/projectiles to find out what the gun likes. FGMM typically will shoot well in most any gun, so I’d start there. If you can’t find any, I’d try to find some 168gr and 175gr SMKs and do some load development since you’re set up for reloading.

Posted: 1/13/2021 3:27:11 AM EDT

[#7]

First place I start when something wont group is re-cut the crown on the barrel. Next suspect is the sight base and rings unless its La Rue, Badger Ordnance, BOBRO, or GG&G or other high end mount. After that the tension on the scope ring screws.

Posted: 1/13/2021 3:45:01 AM EDT

[#8]

Quote History

Quoted:
Light large frames are just about the hardest gun there is to shoot well.

Barrel length has almost nothing to do with accuracy, especially in this context.

View Quote

I have to 16” 308s and they both shoot well (better than 2-3 MOA).

Posted: 1/13/2021 4:30:37 AM EDT

[#9]

Subscribed...
Although I am not ready yet, want to bed my barrel first.

I did find that my barrel had a terrible crown on it from Armalite, with it being off center from the bore.
And the muzzle brake I bought for it didn't sit in-line with the bore.
Have that all straitened out now, so the barrel bedding is next.

Posted: 1/13/2021 5:05:49 AM EDT

[#10]

over-torqued muzzle device?

Posted: 1/13/2021 10:55:55 AM EDT

[#11]

14.5 inch barrel DPMS at 100 yards prone off the Grip Pod. Leupold 1.5 x 5 scope. 6 shots - 2 Hornady TAP 150 gr, 4 mixed 147 gr NATO Milsurp of IIRC, Aussie 1988, DAG 1990, MEN 1993, LC 2006.
Flyer is most likely my fault. I wanted to see if they would all shoot to same POA/POI. They did.

Attached File

Posted: 1/13/2021 11:38:00 AM EDT

[#12]

I have a Colt LE901 “S” 8.4 lbs and 16” bbl
With only 3x ACOG it shoots MOA with
IMI surplus
British Surplus (Less than 1”)
German Surplus
Swiss surplus
PMC -VERY accurate less than 1”
Magtech
Privi Soft points VERY accurate less than 1”
It’s amazing

Posted: 1/13/2021 11:52:39 AM EDT

[#13]

Quoted:
... a Knights EMC clone build ... 16" Noveske barrel and I threw a Trijicon 1-8X on it.

View Quote

Who built it?

Posted: 1/13/2021 12:26:04 PM EDT

[#14]

Quoted:
I purchased a Knights EMC clone build from a member while back. 16" Noveske barrel and I threw a Trijicon 1-8X on it.

Cannot get this gun to shoot better than 2 MOA and that's rare. Typically 2.5 MOA to 3 MOA. Started with some surplus ammo and moved to handloads. Using Hornady 150 gr SST's, LC brass, Winchester primers, Varget powder.

I've got several rounds loaded up to take it out and perform the OCW test on it when weather permits.

Just wondering if maybe a 16" barrel isn't enough to stabilize the rounds and be a ~1 MOA gun and I'm beating my head against the wall trying to get it to be.

View Quote

It's your ammo.

16" 308 can be, and often times are extremely accurate.

You have tried ball rounds and 150 SST rounds, neither of which are known for being overly accurate or consistent.

As mentioned before, try a 155, 168 or 175 SMK with Varget, IMR4064 or another reputable stick powder. That will tell you the accuracy potential of your barrel.

Posted: 1/13/2021 5:24:27 PM EDT

[#15]

I just finished building one with a 16" bbl. I'll have it and a new 24" bull barreled 6.5 creedmoor out at the range on the 23rd breaking in barrels and sighting in scopes. Once I blow through the 150 factory loads, I'll reload the brass, working up some handloads with some 168 Hornady ELD bullets. I'll be curious what it can do with the factory 150s.

Posted: 1/13/2021 6:54:14 PM EDT

[#16]

I did up a 16" .308 last year. It's my favorite to fire now besides the 6.8
I've fired nothing but my own 172g loads through it. The farthest I've shot it so far is 350 yds. Been getting averaged groups of 5" at 350 or a hair less with it.
The 172 grain pulls were from M118 pull down ammo. Bought 2 .50cal cans full of them.

Posted: 1/13/2021 9:49:42 PM EDT

[#17]

Have you cleaned the barrel really well ?.. then tried a single type of known GTG ammo ( as mentioned FGMM 168gr is one of the "standards" )

And no offense intended at all... is this your first Large Frame AR ?

They are a completely different beast to master then a AR15.

If you could , please describe your bench technique's.

Posted: 1/14/2021 12:01:02 AM EDT

[#18]

Thank you all for the replies.

I think likely it is a combination of many things mentioned. At the top, being the type bullet I'm trying to use. I'm pretty committed to it as I have several thousand of them and I like the idea of more of a hunting bullet than a target bullet.

I think getting some good factory ammo and seeing if the groups improve is important. If not, I need to start looking at some of the physical aspects of the gun mentioned.

I don't shoot from a bench. Prone only. bipod with rear bag. Totally relaxed with the goal being just a "trigger puller" while using natural point of aim.

Posted: 1/14/2021 12:53:57 AM EDT

[#19]

Quote History

Quoted:
I did up a 16" .308 last year. It's my favorite to fire now besides the 6.8
I've fired nothing but my own 172g loads through it. The farthest I've shot it so far is 350 yds. Been getting averaged groups of 5" at 350 or a hair less with it.
The 172 grain pulls were from M118 pull down ammo. Bought 2 .50cal cans full of them.

https://www.ar15.com/media/mediaFiles/89/20200510_094020-1418754.jpg

View Quote

That is a beautiful rifle.