AR barrel nut question

[guns_not_groceries]

I recently picked up a VTAC extreme rail (almost identical to troy's trx extreme). The included barrel nut has much thinner teeth compared to the stardard barrel nut and my multi-tool has a tendency to slip over the teeth. I was able to get the barrel nut on and torqued to 80 ft/lbs with the gas tube lined up, but read over at ar15.com that you should loosen and re-torque the barrel nut 3 times to "seat" the threads. I made one attempt to loosen it, but the wrench wants to slip over the teeth. So, is it worth ruining the barrel nut to "seat" the threads? Or is that just a bunch of typical ar15.com bs?

Thanks in advance.

 

[thayton]

Usually you stage up, 60-70-80, it just depends on the tolerances of receiver thread and barrel nut, I think Armalite has a bulletin on their website

 

[technetium-99m]

I just spin it on and crank the nut down until I get one of the holes lined up. If you got the nut torqued down to 80 I think you're good to go.

But seek an experts advice, I know notsing!

 

[doctorjj]

I think 80 is way overkill. Even if you didn't "seat" them, you'll be fine.

 

[Wall]

I just spin it on and crank the nut down until I get one of the holes lined up. If you got the nut torqued down to 80 I think you're good to go.

But seek an experts advice, I know notsing!

This is what I've done also.

 

[CAR-AR-M16]

From TM 9-1005-319-23&P, page 3-41

8. Engage threads of barrel nut assembly (9) with upper receiver assembly (8).

9. Using combination wrench (10) and torque wrench, torque barrel nut assembly (9) to 30 ft-lb (40.5 N-m). Torque is measured when both wrenches are used together.

NOTE: Three times torquing procedure provides for a better thread fit and prevents barrel nuts from becoming loose. Do not use the torque wrench for loosening.

10. Make certain all three drive pins or the teeth on combination wrench are engaged with barrel nut assembly (9). Loosen and repeat torque operation. Then loosen the barrel nut again.

CAUTION: Do not torque over 80 ft-lb (108 N-m) while tightening the barrel nut assembly to the next hole, to allow for proper alignment of gas tube.

 

[liliysdad]

Ive never torqued an AR barrel nut. 30ft-lbs is just a bit past snug, so its kinda hard to screw it up.

As for the Troy barrel nut, the notches are quite shallow due to the small OD of the tube. I use a PRI barrel wrench, as it engages five teeth instead of three, and it works much better.

 

[guns_not_groceries]

Sounds like I should be fine. Next time I'll re-torque it 3 times. Thanks for the peace of mind guys.

 

[KurtM]

80 FOOT POUNDS???? Well I guess if you torque it untill it breaks then back it off a quarter turn you should be good to go!

BTW ALL the accuracy guys I have ever talked to from Accuracy Speaks to Clint McCee, to Krieger they just hand tighten and then advance to the NEAREST hole to align gas tube.....80 FT/LBS???? GEEEEZUUUSSSSSS!! Good way to spring an upper if you ask me! And NO I don't give a hoot what the TM manual says! KurtM

 

[doctorjj]

BTW ALL the accuracy guys I have ever talked to from Accuracy Speaks to Clint McCee, to Krieger they just hand tighten and then advance to the NEAREST hole to align gas tube.....80 FT/LBS???? GEEEEZUUUSSSSSS!! Good way to spring an upper if you ask me! And NO I don't give a hoot what the TM manual says! KurtM

That's what I did. Hand tight, then the next hole. And I'll tell you, with an aluminum barrel nut like the one on a Clark Carbon fiber handguard, combined with the aluminum receiver, it gets really tight really quick. There's not much stretch. Ever put on a set of aluminum wheels right after you out on a set of steel wheels? There's just not as much stretch as there is with steel. The next hole, after hand tight, was ALL my strap wrench wanted anyway.
Like I said before, 80 ft lbs is way overkill.