How much does buffer weight effect accuracy?

[david walter]

How much does buffer weight effect accuracy?

Asking because my 6ARC is being finicky with factory ammo, and I think I may need to add buffer weight to increase lock time?

I’ve shot it with a carbine H1 buffer, and a rifle buffer.

 

[nn8734]

It may be helpful to expand up by what you mean by “finicky” as well as share what rifle, factory ammo you have shot along with some pics of the groups at 100.

 

[david walter]

Faxon 18”
1 in 8” twist
Hornady factory 108 ELD-M
2” group at 100.

other handloads @2”-3”

 

[alamo5000]

Faxon 18”
1 in 8” twist
Hornady factory 108 ELD-M
2” group at 100.

other handloads @2”-3”

That's not going to be your buffer. More like your barrel.

 

[celltech]

The bullet is long gone before your bolt even thinks about moving. I would look elsewhere...

 

[david walter]

I’m going to try and tweak some handloads before I send it on its way.

But, I expected better out of the box.

 

[mheimer_45]

I can almost guarantee it’s not the buffer but the first word in your build specs. Just because there expensive doesn’t mean they’re good.

 

[alamo5000]

I’m going to try and tweak some handloads before I send it on its way.

But, I expected better out of the box.

There has been more than one report that Faxon 6 ARC barrels are not very good. Given that was from a while back when I was researching barrels for my build.

 

[Steel head]

Well that’s a new one!

 

[Earnhardt]

Adjustable gas block?
Gas system?

 

[shax2lex]

Adjustable gas block?
Gas system?

This^^^

 

[Sogan]

I’d say barrel. Nothing fancy with a Faxon, especially if you are expecting sub moa groups with factory ammo

 

[david walter]

I will polishing with a paste help the inside of the barrel or using the tubs polishing system?

 

[nn8734]

I will polishing with a paste help the inside of the barrel or using the tubs polishing system?

Lol, polishing w/paste (Turtle Wax)? It’s not a car.

Buy a new, SS match grade barrel from a reputable manufacturer. Then enjoy the rifle as you originally intended.

 

[david walter]

I meant Flitz, but I guess sarcasm adds to the lively discussion

 

[nn8734]

I meant Flitz, but I guess sarcasm ass to the lively discussion

Wut?

 

[Sogan]

I will polishing with a paste help the inside of the barrel or using the tubs polishing system?

You could try it Tubbs. Not sure if it’s made to fix that big of an issue tho

 

[6.5SH]

Is just a dud barrel if it can't shoot the match ammo well that it was designed for.

 

[GONE BAD]

Well I guess I need to jump in here. LOL
I picked up a Faxon barrel and their bolt head for a 6ARC build from Ranier Arms.
It has turned out to be one of my best shooting rifles!

I posted on the 6ARC thread when I ordered it and heard pretty much the same about how bad they were.

Anyway fast forward to today and I am absolutely thrilled with the outcome of this rifle!
Wasn't going to put a lot of money into it and as of now I haven't but that will soon change.
Added improvements: a decent scope for starters and maybe a different stock.
That's it.
I did call Faxon and asked what size they drilled the gas port and what buffer system they used got the answers and it has been GTG.
OP, hope it works out for you. I'd call Faxon and tell them what you got and see what they say.
I bet they'll treat you right

 

[GONE BAD]

OP, the twist is probably not going to work out with heavy bullets in that barrel
Mine has a 1:7.5 and is 20" heavy fluted SS match.
I get ejector swipe with Hornady 108 match and case shoulder grows only 3 thousandth after 1st firing .
And NO I'm not using an AGB.

 

[david walter]

I reached out to Faxon, their reply:

Thank you for taking the time to contact us! We apologize that you are having such accuracy issues with your barrel. Here is a short list of things we like to check off in diagnosing accuracy issues.
Headspace (have the bolt and barrel been checked with Go and No Go gauges?)
Muzzle device (What muzzle device is mounted and has the firearm been tested without it?)
Optic (are you using an optic and if so, is it mounted securely and zeroed?)
Receiver (Is the receiver face squared and trued or lapped? Is the barrel nut torqued down enough to hold the barrel square to the receiver?)

These are the most common reasons we've seen for accuracy issues on rifles after shooter error. Out of curiosity, at what range are you seeing these groups? This could give a better idea as to what exactly is causing the issue.

Also, while we are more than happy to help troubleshoot, the Heavy Profile 6mm ARC barrels are a Brownells exclusive so you will need to go through Brownells for a warranty replacement or return.

Haven't checked headspace
I took the muzzle device (AAC 300 BO adapter for a 7.62 SDN-6) off last night, and intend to reshoot it this week.
Optic is a proven elsewhere SWFA 6X MQ
Receiver is an out of the box Anderson, barrel is installed and torqued correctly.
Range is 100 yards, with an anchored wood bench

 

[6.5SH]

Another thing to try is let someone else shoot it. Their next step will be to blame the shooter.

 

[GONE BAD]

Hmmm. Then send it back to Brownells.
Now that is easy.
I sent a BRN upper assembly back to them. I said it didn't function right and that was that. No question asked

 

[aslrookie]

FWIW, I had a Faxon 224V barrel that shot lights out and the Valkyrie is supposedly more "finicky" than the 6mm ARC is supposed to be.

 

[Ravenworks]

I reached out to Faxon, their reply:

Thank you for taking the time to contact us! We apologize that you are having such accuracy issues with your barrel. Here is a short list of things we like to check off in diagnosing accuracy issues.
Headspace (have the bolt and barrel been checked with Go and No Go gauges?)
Muzzle device (What muzzle device is mounted and has the firearm been tested without it?)
Optic (are you using an optic and if so, is it mounted securely and zeroed?)
Receiver (Is the receiver face squared and trued or lapped? Is the barrel nut torqued down enough to hold the barrel square to the receiver?)

These are the most common reasons we've seen for accuracy issues on rifles after shooter error. Out of curiosity, at what range are you seeing these groups? This could give a better idea as to what exactly is causing the issue.

Also, while we are more than happy to help troubleshoot, the Heavy Profile 6mm ARC barrels are a Brownells exclusive so you will need to go through Brownells for a warranty replacement or return.

Haven't checked headspace
I took the muzzle device (AAC 300 BO adapter for a 7.62 SDN-6) off last night, and intend to reshoot it this week.
Optic is a proven elsewhere SWFA 6X MQ
Receiver is an out of the box Anderson, barrel is installed and torqued correctly.
Range is 100 yards, with an anchored wood bench

Let's see you shot a gun that you didn't headspace?
What is torqued correctly and what tools were used.
I think I'd be easier to get information by waterboarding

 

[S197]

How much does buffer weight effect accuracy?

Asking because my 6ARC is being finicky with factory ammo, and I think I may need to add buffer weight to increase lock time?

I’ve shot it with a carbine H1 buffer, and a rifle buffer.

Items that faxon issued in their email can cause some issues and faxon is known for kicking out duds in all of their calibers.
what mount are you using?

 

[david walter]

Burris XTR signature high rings

 

[david walter]

Are you suggesting that every build you do with an AR you check headspace? And if so, what correlation does that have to accuracy?

 

[Earnhardt]

Since it doesn’t have an AGB to turn the gas all the way off, try removing the standard gas block and tube, and shoot it as a single shot.
And see how it groups then, Without the buffer moving back

 

[S197]

Are you suggesting that every build you do with an AR you check headspace? And if so, what correlation does that have to accuracy?

Always! if a round is not chambered properly each time how could you expect precision? When ever you buy a barrel, buy a matched bolt with it.

What is Headspace and Why Should it be Checked? - Criterion Barrels

Few tolerances found on a firearm are of more importance than headspace. Not only is headspace essential to rifle accuracy, but it is a major safety factor to consider when assembling a firearm.

criterionbarrels.com

 

[6.5SH]

Since it doesn’t have an AGB to turn the gas all the way off, try removing the standard gas block and tube, and shoot it as a single shot.
And see how it groups then, Without the buffer moving back

That's not going to change anything, Faxon is a low-mid tier barrel maker, he just got a dud. BCA is a low tier maker, there are many folks who report getting a good barrel from them but they are the exception, most will not be sub MOA.

ANY barrel maker can put out a bad barrel or a good one. The more you pay the better your odds are of getting a good one.

 

[Ravenworks]

Are you suggesting that every build you do with an AR you check headspace? And if so, what correlation does that have to accuracy?

I'm suggesting that commonsense and procedure dictates headspacing your bolt on ANYTHING.
Did you clean this barrel before you shot it?

 

[david walter]

Yes, I cleaned the barrel.

I’ve never thought that the headspace was as critical on an AR. Guess I’m wrong about that.

again, how does headspace effect accuracy?

 

[nn8734]

Yes, I cleaned the barrel.

I’ve never thought that the headspace was as critical on an AR. Guess I’m wrong about that.

again, how does headspace effect accuracy?

You can’t be serious - Headspace is important on any firearm, ARs included…

That said, You probably don’t have a headspace problem but can check your CH-Shoulder datum on fired rounds and compare the length to your unfired rounds. If you see more than say, .008” or so expansion then you may want to get headspace checked with a set of go/no go gauges just to be sure. If the chamber was too short for factory ammo, the rounds wouldn’t go into battery and the gun wouldn’t fire. If you shoot all reloaded ammo, just setting up the sizing die to bump the shoulder .003-.004 or so will address any concerns about your chamber’s length relative to your ammo’s (you prob know this but just saying in case it wasn’t considered).

You don’t have an accuracy problem either. Accuracy is simply hitting what your aiming at - that’s all shooter.

Your rifle has a precision potential problem (the gun can’t consistently place round after round in roughly the same spot) which is likely rooted in your barrel.

Cut your losses, send it back to Brownells and get a refund so you can buy a better barrel.

 

[david walter]

Thanks for all the responses. I’m sending the barrel back.

 

[david walter]

Just went and checked. It’s not headspace. Twist on the website said 1-8” and the barrel says 1-7” (guilty. I took the parts to my smith and he assembled pretty much from the box and I didn’t check it).

Might just be a dog barrel.

 

[david walter]

Just on the phone with Faxon. They do not make a 6 mm barrel that isn1-7” twist, he said send it back now!

 

[DavidAR10]

How much does buffer weight effect accuracy?

Asking because my 6ARC is being finicky with factory ammo, and I think I may need to add buffer weight to increase lock time?

I’ve shot it with a carbine H1 buffer, and a rifle buffer.

By The Numbers:

1) The round is out of the pipe before the buffer is part of the equation... for accuracy, not brass & parts brutality. Ask Hornady about
"modern cartridge" velocity and the Booger Picker's body being able to affect accuracy after the
breaking SEAR says, "FU!!! interweb Mogul with an IQ three points above plant life when it comes to FIZAKS."

And it doesn't take the integral f(x) by Separation of Parts to figure this crap out...
because IT AIN'T FRACKING GOLF.

2) Proof Research https://proofresearch.com/barrels/ar-type/
TYPE PART NUMBER BARREL LENGTH TWIST RATE GAS SYSTEM LENGTH GAS JOURNAL DIAMETER MUZZLE THREAD WEIGHT MSRP
PR10 101254 16" 10 Intermediate .750 5/8-24 3lbs-4oz $579

DIAGRAM

TYPE PART NUMBER BARREL LENGTH TWIST RATE GAS SYSTEM LENGTH GAS JOURNAL DIAMETER MUZZLE THREAD WEIGHT MSRP
PR10 100677 18" 10 Rifle .750 5/8-24 3lbs-10oz $579

DIAGRAM

EDIT: Best to you in your quest, sir.

EDIT II: Remember @ 3 decades ago: 50mm objective will give your position away!!! Stay with a 40-42-44mm objective if you want to come back through the wire!!!

They would have never made it through puberty, in my father's house.

 

[david walter]

Good info on the proof barrels. Shoulda went there first.

 

[Ledzep]

OP, the twist is probably not going to work out with heavy bullets in that barrel
Mine has a 1:7.5 and is 20" heavy fluted SS match.
I get ejector swipe with Hornady 108 match and case shoulder grows only 3 thousandth after 1st firing .
And NO I'm not using an AGB.

1:8 is perfectly fine for 108's.

I'm in the camp of Faxon probably doesn't shoot so great. Light weight for certain... Accuracy with Faxon IME has not been where I'd like it to be. YMMV.

 

[mheimer_45]

By The Numbers:

1) The round is out of the pipe before the buffer is part of the equation... for accuracy, not brass & parts brutality. Ask Hornady about
"modern cartridge" velocity and the Booger Picker's body being able to affect accuracy after the
breaking SEAR says, "FU!!! interweb Mogul with an IQ three points above plant life when it comes to FIZAKS."

And it doesn't take the integral f(x) by Separation of Parts to figure this crap out...
because IT AIN'T FRACKING GOLF.

2) Proof Research https://proofresearch.com/barrels/ar-type/
TYPE PART NUMBER BARREL LENGTH TWIST RATE GAS SYSTEM LENGTH GAS JOURNAL DIAMETER MUZZLE THREAD WEIGHT MSRP
PR10 101254 16" 10 Intermediate .750 5/8-24 3lbs-4oz $579

DIAGRAM

TYPE PART NUMBER BARREL LENGTH TWIST RATE GAS SYSTEM LENGTH GAS JOURNAL DIAMETER MUZZLE THREAD WEIGHT MSRP
PR10 100677 18" 10 Rifle .750 5/8-24 3lbs-10oz $579

DIAGRAM

View attachment 7652326

EDIT: Best to you in your quest, sir.

EDIT II: Remember @ 3 decades ago: 50mm objective will give your position away!!! Stay with a 40-42-44mm objective if you want to come back through the wire!!!

They would have never made it through puberty, in my father's house.

Why has proof been all the rage lately? I remember 10 years ago “my proof won’t shoot” was as common as “what scope” is now.

 

[david walter]

@Ledzep

load data?

 

[Ledzep]

Why has proof been all the rage lately? I remember 10 years ago “my proof won’t shoot” was as common as “what scope” is now.

"My proof won't shoot" was carbon barrels. They've fixed that. IMO/IME they're the best carbon barrel on the market.

Their stainless pipes that I've had (3 or 4 now) shoot just as good as any of the other top cut rifled barrels.

 

[Ledzep]

@Ledzep

load data?

For 108s? If you're wanting speed and practical precision I've had best luck with Lever evolution. 2nd best luck with cfe223. Follow the book data for gas guns.

Fwiw, Varget almost always hammers, but runs pretty slow for MV.

 

[david walter]

Thx

 

[GONE BAD]

So, David, did you send it back to Brownell or back to Faxon?
Not that it matters, just curious

 

[david walter]

Brownells

they musta got rid of these because the SKU
from my order form shows nothing at all

915-000-097

 

[sheepdog697]

How much does buffer weight effect accuracy?

Asking because my 6ARC is being finicky with factory ammo, and I think I may need to add buffer weight to increase lock time?

I’ve shot it with a carbine H1 buffer, and a rifle buffer.

Are you typically a sub moa shooter with other gas guns?

 

[david walter]

No. But I shoot better than 2-1/2” with all guns.

 

[DavidAR10]

Why has proof been all the rage lately? I remember 10 years ago “my proof won’t shoot” was as common as “what scope” is now.

Get out of your mom's basement and compete.