AR Barrel torque?

[tiger222]

So I am barrelling an upper and at 30ft lbs, the tooth is just a few degrees infront of the barrel gas tube hole ~ torque up to 80ft lbs and it's still not completely aligned.

Is it better to be under torqued or over ?

TIA

[Technical Ted]

So I am barrelling an upper and at 30ft lbs, the tooth is just a few degrees infront of the barrel gas tube hole ~ torque up to 80ft lbs and it's still not completely aligned.

Is it better to be under torqued or over ?

TIA

Does it align between 30 and 80 ft/lbs?

Try torquing it three times: torque-release-torque-release-torque. Final torque to alignment.

Whatever you do, don't go over 100 ft/lbs.

If that doesn't do it, contact AR15barrels for some shims that fit between the barrel and upper receiver.

[carsonwales]

So I am barrelling an upper and at 30ft lbs, the tooth is just a few degrees infront of the barrel gas tube hole ~ torque up to 80ft lbs and it's still not completely aligned.

Is it better to be under torqued or over ?

TIA

How stout is your vice?

I had some trouble like that on a couple of uppers and ended up at my mechanics shop using his 6 inch vise bolted to a steel table that was bolted to concrete...

Whoa!....what a difference!

The ability to apply the force evenly and smoothly without starting and stopping made a millions time easier to get the tube lined up....

Of course high quality hi-temp moly grease and a high quality barrel wrench with a very long breaker bar style torque wrench helped too...

Torque should be measured when the nut is in motion...not the torque it takes to overcome the frictional coefficient of a semi galled nut. The moment you stop turning, the components will gall themselves together...and sometimes it takes tremendous force to overcome that static frictional state....

I stopped measuring torque awhile ago...super stout vise, excellent grease...and good breaker bar and a smooth continuous motion to the arrest point/tube align...helps to have a spotter sighting down the barrel watching the alignment and hollering Whoa!

[ar15barrels]

As you are in west la, you are within a few miles of me down in mar vista.
I recommend a visit to my shop.

[adamsreeftank]

I have used a ft/lbs torque wrench in 5 lb increments and had to go over 85 or 90 on a couple. I think the routine is three times to 30 and then go to 35 and check alignment. If you are under 30, I think you need to go the hard way. But I'm not a professional, so you might want to check with one like Randall.

[RECCE556]

As you are in west la, you are within a few miles of me down in mar vista. I recommend a visit to my shop.

I highly recommend Randall. He is very knowledgable and does great work. Plus he's a nice guy.

If you decide to go with a quality free float rail system, I highly recommend the Daniel Defense Lite rails (and the KAC URX II/III). The barrel nut is COMPLETELY independent of the gas hole alignment so this is NEVER an issue. That being said, if you're stuck with a lesser rail or the standard barrel nut, Randall's Shim Kit will do the trick.

[Blue]

What happens if you go over 100lbs?

[Technical Ted]

What happens if you go over 100lbs?

According to what Randall told me, the receiver threads strip.

[ar15barrels]

According to what Randall told me, the receiver threads strip.

The threads will hold a lot more than 100 ft-lbs.
The receiver will crack along the side from the torque well before threads strip.
Ask me how I know this...

[tiger222]

thanks everyone, and thanks Randy ~ will give it another shot this weekend and if not will come by and see you.

[CaptMike]

The threads will hold a lot more than 100 ft-lbs.
The receiver will crack along the side from the torque well before threads strip.
Ask me how I know this...

Sooooo How Do you Know This?

[C.G.]

Sooooo How Do you Know This?

It is either

[ar15barrels]

It is either

I believe the term used at the time was SH1T!