AR-15 barrel torque best practices

[Holland&Holland]

Ok, so the common torque spec that I have always adhered to for AR barrels has been the 35-80. And of course there is the use anti seize tighten and back off tighten and back off tighten and back off tighten to line up the teeth for the gas tube to fit through. I have always assumed the range is so large in order to accommodate the tube. But what are thoughts on the best amount of torque? Better to be near the top of the range, the middle, or the lower? Any experiences with over torqued or under torqued barrels?

The reason I am asking is that my latest build I am using a barrel nut, that for the first time for me has no teeth to line up so I can torque to whatever I want for a change.

[Ghost]

I use the same method, using grease instead of anti-sieze, torque the last time to 35 then line up the gas tube hole or teeth. I've had some where I've been at the high end or exceeded it to get things lined up properly. As long as you have 35, you should be good to go.

[shooter115]

I shoot for the upper edge of the torque spec.

[UnaStamus]

I use the same method, using grease instead of anti-sieze, torque the last time to 35 then line up the gas tube hole or teeth. I've had some where I've been at the high end or exceeded it to get things lined up properly. As long as you have 35, you should be good to go.

Ditto.

[striped1]

Shoot for the upper end. I shim the barrel for the tightest possible fit. Freeze the barrel and heat the receiver to get it to fit. Use the grease and then torque to 70-75. This should result in the least amount of thermal shift / wander as the barrel heats up.

[Rip Van Winkle]

What I'm going to say may be heresy to some, but here goes.

Barrel nut torque isn't that critical.

That's the reason they give you such a broad torque range. Less than 30 ft/lbs and you run the risk of the barrel nut vibrating loose. Tighter than 80 and you run the risk of deforming the upper receiver, or buggering up the threads.

And make sure you apply some Magic Pixie Dust to the threads.

[Scratch]

I need to get some more pixie dust... My supply is just about gone. If you find a good local source for it, let me know.

[Ghost]

I need to get some more pixie dust... My supply is just about gone. If you find a good local source for it, let me know.

Here
Pixie dust source

[Sigfan220]

What I'm going to say may be heresy to some, but here goes.

Barrel nut torque isn't that critical.

That's the reason they give you such a broad torque range. Less than 30 ft/lbs and you run the risk of the barrel nut vibrating loose. Tighter than 80 and you run the risk of deforming the upper receiver, or buggering up the threads.

And make sure you apply some Magic Pixie Dust to the threads.

I agree. Everything has a torque spec, even oil filters. Do you use a torque wench when changing oil, no. I don't even use a torque wrench anymore on AR's. With some hand guards you are more concerned with alignment than torque anyway, some are a pain to get to work. Nice an snug seems to work fine.

[Ghost]

I agree. Everything has a torque spec, even oil filters. Do you use a torque wench when changing oil, no. I don't even use a torque wrench anymore on AR's. With some hand guards you are more concerned with alignment than torque anyway, some are a pain to get to work. Nice an snug seems to work fine.

You should pay attention to the minimum torque spec so that you achieve proper clamping force.

Use German torque for things that don't matter, gutentight.