torque ar15 barrel back Into barrel extension.

[JohnnyD]

anybody have the know how or can recommend a gunsmith in the Vancouver Portland area that can retorque a 16 inch ar15 barrel back Into the barrel extension? went to take my flash hider off that I've had off before and the barrel started turning. got the barrel nut off and got the extension out. doesn't looks like the index pin is broken just wasn't seated very well.

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[DirectDrive]

anybody have the know how or can recommend a gunsmith in the Vancouver Portland area that can retorque a 16 inch ar15 barrel back Into the barrel extension? went to take my flash hider off that I've had off before and the barrel started turning. got the barrel nut off and got the extension out. doesn't looks like the index pin is broken just wasn't seated very well.

View attachment 408790 View attachment 408791

Yikes !
You basically have a defective barrel there.
The barrelmaker failed to apply the correct torque to the barrel extension.
This part requires around 150 ft lbs of torque, if i recall correctly.
Now, if you torque the extension on properly, your gas port will be out of time with your extension pin.

I'd send it back to the maker.
If they don't immediately send you a new barrel, they suck.

Also, you should not be twisting on a muzzle device against the barrel pin !
Use a vice and barrel blocks, either manufactured or homemade out of wood.
And crazy high torque at the muzzle can wreck accuracy. Follow mfr's directions.

Muzzle device torque is going to be around 30 ft lbs on average, while the BE torque is around 150 ft lbs. That said, monkeying on a muzzle device without barrel blocks should never interfere with the BE torque. You could snap off the pin, though.
I say this because they might try to scold you for not using blocks if you return the barrel.


Vice and barrel blocks...

 

[ron]

Now, if you torque the extension on properly, your gas port will be out of time with your extension pin.

You are correct. Barrels are very cheap right now. A buddy just installed a cheap AR Stoner Varmit
barrel for less than $100 from Midway. It shoots great!! Sub MOA How much will
it cost to have someone try to fix this one? It will make a great tent stake.

 

[JohnnyD]

I'm not even sure who made the barrel to be honest got this one on trade a while back and I'll have to pick up some barrel blocks bug I've have this flash hider off a few times before with no issue and you wouldn't believe how east the barrel came lose. I was hardly applying any force and wouldn' have if t needed it. almost glad I found this out. better then having it come loose while shooting it. thanks for the advice guys guess I'm ordering a new barrel

 

[titsonritz]

This is what happen with improperly treated Nitride barrels. That thing is toast.

 

[HB of CJ]

Send it back. Short answer.

Hundreds of AR15 builds.

 

[JohnnyD]

would love to send it back but got this on trade a while back. he told me it was an Anderson am15 but no markings on the upper so who knows probably a home build. can' complain though orginally only had about 50 bucks into it. just found a bear creek ss 16 inch 1/8 twist 556 barrel carbine length on sale for 49.99 looks like some mixed reviews on it but figured id give it a try. would like to have spent more but just dropped in a rise armament trigger and bought a 15 inch mlok rail so wife's already giving me the stink eye. loads of Christmas present to buy still too.

 

[HB of CJ]

Thank you. A factory return is still not doable? Can you identify who built the gun? If you can do that then perhaps contacting them politely still might work? But if they tell you to pound sand then what? They probably will not tell you the barrel maker.

Getting a new barrel may not be the best course of action. Is the upper receiver damaged in any fashion? A good eye ball look over might not be enough. I am thinking small or hidden cracks that might show up latter. Just me. I am kinda paranoid that way.

Same thing with the bolt carrier group. In particular looking for abe-normal stuff with the bolt head. Locking lug damage. Cam pin hole cracks. Extractor condition. Tweeks in the bolt carrier and gas key. Lots of stuff to look at. Thus a return perhaps being best?

Respectfully.

hundreds of builds. uncounted rebuilds.

 

[JohnnyD]

I had the rifle stipped and in the vise when it happened sure the bcg is fine. the upper I'm doubting had anything wrong with it. I looked it over and didn't see anything and the force it took to separate the barrel was minimal. just wrapped my barrel and put it in the wise and got my gas block and flash hider off and it wasn't all that tight.

 

[HB of CJ]

Respectfully ...

Perhaps not much more we can do here to help. Assuming stuff with an AR15 build may not be the best course of action. If it were me I would just chuck the barrel, upper receiver and the bolt head. The rest I would eyeball very carefully. Know. Do not assume.

More respectfully, this is a good example of not knowing what you do not know what you do not know. One can build your own AR15 but there are several little zingers about the platform that require some knowledge and experience. Barrel torquing is the big one.

Respectfully.

hundreds of AR15 builds. blah, blah.

 

[JohnnyD]

thanks for your opinion. I don' think barrel torquing will be a problem but I am planning on taking it it a Smith to gone over and have the head space checked. shame that the barrels toast it was fairly accurate but it happens. thanks for the advice all

 

[JohnnyD]

well bit the bullet and got a new barrel. was looking around at all the cyber week ling sales and got a bear creek 556 ss 16 inch barrel. know it's not the best but most of the reviews are good and was on sale for 49.99 couldn' pass it up. taking it to northwest custom firearms on Tuesday going to have jon torque on the barrel nut as the guntec rail uses a funny one that takes a slim crows foot wrench and check for head space. hopefully will be breaking it in on Thursday.

 

[JohnnyD]

appreciate the advice everyone.

 

[Boboclown]

For future reference, you can buy a wooden post and use some drillbits to make a barrel block.

Do this instead if you're trying to be cheap.

 

[HB of CJ]

The barrel gets locked down VERY tight using some sort of pad to keep the scratches or marks off the barrel. A big 5 inch bench vise is needed. Use the old fashioned aluminum barrel vise jaws that fit into the vise.

The upper receiver floats. The barrel get torqued up using a good certified click type torque wrench to about 40-42 pounds. Do not forget to reduce the torque due to the barrel wrench length adding leverage.

Getting that perfect barrel nut to gas key alignment is the difficult part. The gas tube must not touch anything. Plop test needed. A horrible OEM design.

If things do not line up and they will not, gently shave just a very small amount off the upper receiver front flat. Then try again. Barrel off and on, off and on, eventually the barrel will torque up exactly correct. Dry. No lube at all.

There are other good posts on this Excellent Forum on torquing up an AR15 barrel properly. Some methods are wrong. Ours are old school correct.

We will leave barrel indexing with the OEM forged steel pin type front sight base using OEM rear iron sites for later. More fun and games.

Be sure to use a steel front gas block. The aluminum ones burn out quickly.

Respectfully. No big dog in this. Just trying to help.

 

[JohnnyD]

thanks for the advice all. got it done just waiting on a new flash hider with shim kit. I appreciate NW custom firearms for the quick work. hoping to take it out next week.

 

[HB of CJ]

We used the old peel washers to align flash hiders. Worked great.

 

[JohnnyD]

i read that my crush washer is toast. was just going to get a new one but the shim kit came with 25 pieces and were only a few dollars more. also going with the old school three prong flash hider. hope it shoots as good as it looks

 

[Sniper03]

Johnny,

You are in luck since it does not have the normal Front Sight A-Post which they are also predrilled for the Taper or Dowel Pins. But your barrel extension was not assembled correctly.From the Factory. Barrel Extensions are Torqued on the Barrel threads at around 150 Ft. Lbs. If you did have the standard A-Post normally re-torqueing the Barrel Extension throws off the alignment off with the Index pin causing the Rear and Front Sight alignment to be misaligned! Signs are the Rear Sight Aperture being way over to one side in the Rear Sight Aperture Housing to zero the rifle. But you will need to find someone that has the special tool and holding blocks to torque the Barrel Extension back on the barrel. The special socket tool fits into the locking lugs inside the Barrel Extension Lugs and on a torque wrench.
As far as re-torqueing the Barrel Nut or Quad Rail Barrel Nut it requires one onto the Receiver. The standard Barrel Nut should always be torqued to a minimum of 35 Ft. Lbs. Obviously, it may be slightly more in order to align the Gas Tube with the opening in the Receiver. And as a side note! *Never use a Crush Washer more than once unless you hate the guy who is going to work on it on the barrel after you. They will have to cut it OFF!

Sniper 03

 

[DirectDrive]

Johnny,

You are in luck since it does not have the normal Front Sight A-Post which they are also predrilled for the Taper or Dowel Pins. But your barrel extension was not assembled correctly.From the Factory. Barrel Extensions are Torqued on the Barrel threads at around 150 Ft. Lbs. If you did have the standard A-Post normally re-torqueing the Barrel Extension throws off the alignment off with the Index pin causing the Rear and Front Sight alignment to be misaligned! Signs are the Rear Sight Aperture being way over to one side in the Rear Sight Aperture Housing to zero the rifle. But you will need to find someone that has the special tool and holding blocks to torque the Barrel Extension back on the barrel. The special socket tool fits into the locking lugs inside the Barrel Extension Lugs and on a torque wrench.
As far as re-torqueing the Barrel Nut or Quad Rail Barrel Nut it requires one onto the Receiver. The standard Barrel Nut should always be torqued to a minimum of 35 Ft. Lbs. Obviously, it may be slightly more in order to align the Gas Tube with the opening in the Receiver. And as a side note! *Never use a Crush Washer more than once unless you hate the guy who is going to work on it on the barrel after you. They will have to cut it OFF!

Sniper 03

Wouldn't matter if he had an FSB (A-frame front sight) or not.
As previously mentioned , the gas block (whatever type) would be "out of time" if one tried to re-torque a mis-installed barrel extension.
But the point is moot, since the OP bought and installed a new barrel.

Barrel nut torque range in the M16/M4 TM (Tech Manual) is 30 ft lbs to 80 ft lbs
I start looking for alignment as I pass 30 and try to stay under 40
That's "wet torque" using the specified AeroShell 33MS on the threads and torque shoulder