Any magic to an AR barrel extension?

[SteveOak]

It looks as though I am going to go through with the AR thing. Is there any magic to the barrel extension? Any particular one better than the rest?

Thanks!

 

[Fast14riot]

Looking to install your own? Aside from getting one machined to fit your receiver, nothing really special. They are installed i believe to 150-175ft/lbs dry. Pin is 1/8" diameter 3/16" long. Maybe give John at White oak or John at Keystone Accuracy a call, both are top tier AR smiths.

 

[SteveOak]

I would like to ask a friend of mine if he want to fit an AR barrel for me. It looks like the extension is a bit complicated but the rest of the barrel looks no more difficult than a barrel for a bolt rifle. My friend is away on vacation with his wife and I don't want to bother him now.

If someone makes barrel extensions that are better than most, I would buy one.

 

[LVLAaron]

White Oak Armament is the source for barrel extensions.

AR barrels a (high pitched voice) kinda (end high pitched voice) complicated to get right.

Complicated isn't the right word. There's more steps. It's not hard, but... more steps.

 

[jelenko]

I would like to ask a friend of mine if he want to fit an AR barrel for me. It looks like the extension is a bit complicated but the rest of the barrel looks no more difficult than a barrel for a bolt rifle. My friend is away on vacation with his wife and I don't want to bother him now.

If someone makes barrel extensions that are better than most, I would buy one.

https://www.whiteoakarmament.com/barrel-extension-m4.html WOA

Lija also makes extensions spec'd at .999
https://riflebarrels.com/shop/accessories/m4-type-barrel-extensions/

 

[padom]

When it comes to barrel extension, large or small frame, I like ones that are honed and polished and aren't sharp as hell on the backside of the lugs for my precision AR builds.

Because of this, I send my smith's JP QPQ honed and polished extension for my large frame gasser builds.

Finding a similar extension for small frame is harder, but I have been buying lilja since BAT stopped making extensions. I then use a cratex bit and just hit the back side of the lugs located in the 2-4 o'clock position to knock that sharp edge/bur off. If you stick your finger in the extension and feel the backside of the lug edges from 2 - 4 o'clock you'll see what I'm talking about.

The main reason why, is because of brass damage. These sharp extensions that aren't polished take gouges out of the neck and shoulders of your brass as the case is pulled out the chamber after firing and the ejector is putting that pressure to the right side on those sharp lug corners.

With a honed extension you don't have this and brass looks like its been fired in a bolt gun.

About the only thing I do or look for when building a custom Precision AR on a Bartlein, Kreiger, etc.

 

[Fast14riot]

White Oak Armament is the source for barrel extensions.

AR barrels a (high pitched voice) kinda (end high pitched voice) complicated to get right.

Complicated isn't the right word. There's more steps. It's not hard, but... more steps.

Good AR smiths time the gas port to be in the groove when threading.

 

[LVLAaron]

Good AR smiths time the gas port to be in the groove when threading.

I'm curious how you get that lined up.

 

[urbanrifleman]

White Oak Armament is the source for barrel extensions.

AR barrels a (high pitched voice) kinda (end high pitched voice) complicated to get right.

Complicated isn't the right word. There's more steps. It's not hard, but... more steps.

When you get there just buy the barrel too. You'll save time and money in the long run.

 

[LVLAaron]

When you get there just buy the barrel too. You'll save time and money in the long run.

Totally agreed. I have a White Oak Precision barrel... it is bananas accurate. One hole groups at 100, over and over and over and over.


However, Some people want weird chamberings. I've always wanted to ask them if they'd sell me a finished, but unchambered barrel.

 

[urbanrifleman]

Totally agreed. I have a White Oak Precision barrel... it is bananas accurate. One hole groups at 100, over and over and over and over.


However, Some people want weird chamberings. I've always wanted to ask them if they'd sell me a finished, but unchambered barrel.

Darn Wilson barrels....

 

[VA_XTC_Shooter]

Good AR smiths time the gas port to be in the groove when threading.

That falls in the myth category.
There has been no evidence the port in a groove is better.
John H posted a long time ago he only did it because people complained it wasn't there, so he wanted to save time from the phone.
Robert Whitley claims based on all of the barrels he has done in the groove is actually worse than hitting land and groove.
There is a lot of dogma in the rifle accuracy world that seems to logically make sense, but in reality doesn't do what we think it does.

 

[urbanrifleman]

That falls in the myth category.
There has been no evidence the port in a groove is better.
John H posted a long time ago he only did it because people complained it wasn't there, so he wanted to save time from the phone.
Robert Whitley claims based on all of the barrels he has done in the groove is actually worse than hitting land and groove.
There is a lot of dogma in the rifle accuracy world that seems to logically make sense, but in reality doesn't do what we think it does.

Preach brotha preach.

Lotta horse pucky being sold as gospel.

 

[padom]

Testing and talking to Hollinger, Frank White @ Compass Lake and John @ Keystone testing barrels for years, they said it made no difference. I tested this heavily and found zero difference in accuracy...

 

[LVLAaron]

Darn Wilson barrels....

Krieger, actually.

 

[gunsandgunsmithing]

I think it was BAT that made a fine thread bbl extension. I liked those but haven't seen them in a while...and I've looked often. The fine thread is less deep and gives a little more support over the chamber. Anyone know if these are being made anymore..and of good quality?

 

[urbanrifleman]

Krieger, actually.

Oh very nice. I still have my Krieger made 7.7 on my space gun. Still hammers after 5000 rounds.

 

[WSnyder]

I think it was BAT that made a fine thread bbl extension. I liked those but haven't seen them in a while...and I've looked often. The fine thread is less deep and gives a little more support over the chamber. Anyone know if these are being made anymore..and of good quality?

I have been buying lilja since BAT stopped making extensions.

 

[msalm]

I’ve made AR barrels in many calibers from 17 Rem, 20 calibers, 224 and 6mm cals (223 and Grendel based), all the way up to the 458 SOCOM. Best barrel extensions by far were the BAT extensions. There’s a guy making copies of them now (BAT WILL FORWARD YOU HIS CONTACT INFO) but not sure they’re as good. Used to be after threading/chambering a blank through the headstock I’d spin on the bat extension and test runout…it was always under .001”. I’ve had some OEM type have .015” of runout. Last few I’ve used were very good however, around that .001” runout range. Don’t remember the brand, but you could tell they were better finished with clean machining on all critical surfaces.

 

[Pawnee Bill]

It looks as though I am going to go through with the AR thing. Is there any magic to the barrel extension? Any particular one better than the rest?

Thanks!

Just call the good folks at Compass Lake Engineering and order you a Krieger barrel of your specs and they will install a top quality barrel extension and ship the barrel to you. No muss, no fuss and no worries of any kind.