Gunsmithing AR 15 Barrel Nut Torque

[NavyshooterM40]

What is the proper torque for an AR-15 barrel nut?

 

[GH41]

Tighten to 30 foot pounds then as much more as necessary to line up the next slot for the gas tube. DO NOT exceed 80 f/p! If the nut doesn't have to be indexed tighten to 50 f/p.

 

[arocholl]

According to the Marines Armory Manual:

Tighten to 35 foot pounds
Loosen

Tighten to 35 foot pounds
Loosen

Tighten past 35 foot pounds until gas tube holes are aligned. Do not exceed 80 foot pounds.

 

[bptactical]

Be sure to use a non graphite antisieze or grease on final assembly. The 3 torque and loosen cycles should be with dry and clean threads, it burnishes the threads and allows for an accurate final torque reading.

 

[damoncali]

Keep in mind those torque values assume you'll be using mil spec moly grease on the threads.

 

[kyle528]

If the barrel nut has not yet been mated to the threads on the upper, tighten to 30-35 foot pounds and then take completely off. Do this a few more times to properly mate the threads, you will be thankful you did this when you decide to take the barrel off later. After that, tighten the nut back to 35 pounds and check for gas tube alignment. If the gas tube won't fit, increase torque by 5 pounds and try again. Do this until the gas tube fits but DO NOT go above 75 to 80 pounds or you run the risk of stripping threads. Then check gas tube alignment with gas block and bolt carrier key. Then go shoot and have fun

 

[ATTom]

Please make sure you do it with a dial torque wrench. I can never look at the needle ones and get an accurate reading while trying to turn the wrench. Maybe I'm just uncoordinated?

As a side note Auto Zone rents dial torque wrenches for 100.00 deposit. You get a total refund when you return the tool. Helps lessen the cost if your only building one rifle a year.