AR15 barrel extension

[rdnktrkr]

I decided to replace my old clamshell handguard and gas block for a free floating one, while trying to loosen the birdcage my barrel came loose from the extension. I've contacted the MFG but I've had this gun for years so I don't expect much.
This is a seldom shot gun used mostly as a quick access home defense AR. Is there any help for this barrel or should I just look for another? If so is there any brands I should stay away from?

 

[BBBBill]

It should not be a problem to reinstall the extension.

 

[rdnktrkr]

When I read up about the torque specs I saw 150ft lbs, Is that correct? I my barrel blocks are hardwood plates with leather inserts, I don't think they would allow that much torque. Should I just align the gas hole and the pin and call it good?.
I'm thinking a new barrel would give me piece of mind. Another thought would be to change calibers, 350 Legend, 300 hamr, something that would use the same bolt.

 

[Blue68f100]

Yes on the torque, 150 ft/lbs. Use some rosin if you have it, it will help keep it from spinning in the barrel clamp. Some even add some red LocTite too. Go as tight as you can if you can not reach the 150 ft/lbs mark, and use the LocTite. The pin may or may not align up. My guess is that it will be off, since it was not fully torqued. Beside the pin should go into the threads some if done right.

 

[Telekinesis]

Unless you’re set up to do it, I would just buy a new barrel and be done with it. Especially if this is a defensive weapon.

If you want to try fixing your original barrel, yes you’ll need to be aware of the torque requirements (I’m not sure if 150 ft-lbs is correct but you’ll want to look for some documentation on that number). As you mentioned, you will need to make sure the gas port is aligned with the pin (which also should take care of the feed ramps).

The biggest issue is that the barrel extension controls your rifle’s headspace. Not to get too detailed, but at minimum you’ll need the right gauges to confirm that the barrel and extension is within spec once everything is tightened down. Most SAAMI chamber specs have a Min-Max of +/- 0.010”, but you’re really shooting for a window of less than 0.005”.

If it is out of spec, then you’re going to need a lathe and a lot more tools and measurements to figure out what dimensions need to change in order to get everything back to where it needs to be.

So yeah, unless you’re set up to do that kind of work and are a hobby/professional machinist it’s going to be easier to just buy a new barrel (or a new upper).

As far as recommendations, I would say avoid whoever made that upper. A barrel extension shouldn’t come off when you’re trying to remove the flash hider, and that points to a lack of QC on either whoever made the upper or whoever their barrel supplier is. And if they got the barrel extension wrong, I wonder what else they missed. At a minimum I’d be concerned that the gun was out of headspace before the extension separated.

Anyway, barrel and upper recommendations are dependent on what you want the gun to do and what your price range is. But for a defensive weapon I wouldn’t recommend trying to cut costs. I’d personally go with something like a BCM.

 

[12Bravo20]

That wouldn't be a Radical Firearms barrel is it?

Years ago, Radical Firearms was notorious for this exact problem.

If so, I recommend a new barrel.

 

[rdnktrkr]

Not a Radical Firearms. I'll look and see if there is a manufacturer marked on the barrel, I won't name them as long as they are still communicating with me about this issue but they are known as a cheaper line. I keep this gun at the back door in case something is in my yard that shouldn't be and is being aggressive.
I've probably had this gun for around 9 or 10yrs I just don't shoot it much, maybe 1 or 2 mags every year or two, My go-to ARs for shooting have longer barrels or/and different calibers.
I'm looking at a Ballistic Advantage barrel if I stay in 223 or I've found a Shaw barrel in 300hmr that might be a fun build, this is the wrong upper for a 458 Socom so I'll keep that one on the back burner

 

[Blue68f100]

Not a Radical Firearms. I'll look and see if there is a manufacturer marked on the barrel, I won't name them as long as they are still communicating with me about this issue but they are known as a cheaper line. I keep this gun at the back door in case something is in my yard that shouldn't be and is being aggressive.
I've probably had this gun for around 9 or 10yrs I just don't shoot it much, maybe 1 or 2 mags every year or two, My go-to ARs for shooting have longer barrels or/and different calibers.
I'm looking at a Ballistic Advantage barrel if I stay in 223 or I've found a Shaw barrel in 300hmr that might be a fun build, this is the wrong upper for a 458 Socom so I'll keep that one on the back burner

You can go to 458 SOCOM by just buying the upper. A std AR-15 upper will need the ejection port enlarged. This was the 1st AR I built to deal with hogs in my area. All my neighbors know when I fire it since it has a unique bark to it.

 

[rdnktrkr]

I've been looking closely at the 458 socom and currently have 2 lowers I've completed in my safe waiting and I've 3d printed some followers to change out in 20rnd mags.
The thought of 300 or 350gr bullets in an AR makes me smile. Around here the average shot during hunting season is less than 100yrds.