ar barrel nut question

[simplicity]

I just bought a a3 upper to replace the a2 upper on my AR and I was wondering if anyone could tell me the amount of torque you need to apply to the barrel nut, I have the wrench and everything apart. Just need the torque spec so I'm sure I'm getting it back together properly.

[KN]

I see no one has replied yet so I'll chime in here. I don't know if there is a actual torque spec or not. When you install the new barrel the nut has to be positioned so that the gas tube lines up with one of the holes in the nut without binding any. It has be lined up with the bolt. So you are limited on where you have to stop in order for everything to line up. When I installed mine I tightened the nut fairly tight and then inspected how the hole lined up and then continued tightening untill it was correct. The first time I did this I didn't get it tight enough and ended up with a loose barrel after some shooting. That really screwed with the accuracy. If your not sure about it you may want to let some one more experienced do it.   KN

[GregP42]

I just bought a a3 upper to replace the a2 upper on my AR and I was wondering if anyone could tell me the amount of torque you need to apply to the barrel nut, I have the wrench and everything apart. Just need the torque spec so I'm sure I'm getting it back together properly.

This is what I found in the field manual
Barrel Nut - 31 Ft. lbs. Minimum, not to exceed 80 Ft. Lbs. to align the next slot in the barrel nut.

Greg

[simplicity]

Thank you very much for the replys and to let you know I learned a exspensive lesson that i will not make the same mistake. In tightening the barrels nut enough to line up the gas tube slot I accually cracked the upper I had it in wood up close to the front, but I screwed up lesson learned, working on AR's is still new to me and I will conquer them. ONce again thatnks for the replys.

[KN]

Don't feel too bad, I ruined a reciever by putting it a vice wrong while either loosening or tightning the nut. I don't remember which. Twisted the reciever. Expensive lessons.   KN

[simplicity]

I have a new reciever on the way, and I went and made a set of barrel jaws for my vice so the reciever won't even be touched, I'm going to try to straighten out the other ruined reciever and have it welded and try to clean it up  I figure at this point with it I really have nothing to lose with the ruined one and it 'll be fun to see if I can save it. One of the perks about being a machinist.