How to install Barrel Extension on AR-15

[Anon02]

Hi,
I have an AR-15 barrel that the extension has come loose. How do these get installed? Any tricks/special tools to use?

TIA,
Greg

[Reconsnake]

This is going to be difficult, as the alignment of the gas hole is of utmost importance. As I understand it, the extension is screwed on, and then the gas hole is drilled, so that the alignment is absolutely perfect. If this system does not seat in the exact same spot, then the rifle may never function properly because the gas hole is no longer aligned and will not allow gas down the tube. Barrels are cheap, you may want to buy a new one, save yourself the trouble.

[chuck762]

How old is the barrel? If it is new I would send it back to the manufacture since you can not get it correctly torqued and keep the timing between the gas port, locating pin and head space correct.

[CRTguns]

defective barrel. The index pin is upposed to engage to at least the bottom of the threads to lock the thing together. mfg shortcuts

On the bright side, if the mfg is not helpful, it's only about a $20-$30 job to re-do the thing.

[Anon02]

Thank you all for the replies. I contacted the vender and they are correcting the situation. I appreciate all the information!!

[Cokebottle]

Related question regarding headspacing.

Am I correct in assuming that headspacing is a function of the barrel and extension, and that a barrel may be removed and installed in a different upper receiver without concern... or, if one were to purchase a stripped upper and buy a barrel from a shop like Riflegear, is there any adjustment needed and how to do it?

[eaglemike]

Related question regarding headspacing.

Am I correct in assuming that headspacing is a function of the barrel and extension, and that a barrel may be removed and installed in a different upper receiver without concern... or, if one were to purchase a stripped upper and buy a barrel from a shop like Riflegear, is there any adjustment needed and how to do it?

Supposed to be plug-n-play. I've checked a few, and the headspace has always been in tolerance.

Randall has a drawing somewhere...... like you say, it's supposed to be controlled by the assembled extension/barrel assembly.

all the best,
Mike

[Anon02]

The Barrel was bought approx one year ago, but has only had about 60 rounds down range.
My barrel wasn't one of the AR15 performance barrels, and it has been sent back to the manufacturer. They are trying to get things squared away for me.
Thanks again for all the suggestions!