Gunsmithing AR-15 bbl install quick question

[Tactical30]

I am installing a new bbl on my new AR build (6.5 Grendel)
and I am tightening the barrel nut to line up with the gas tube but it seems like if I want it tight-tight im going to have to really torque on the nut to get it to the next slot but if I leave it at the slot before it, its tight but not real tight but I dont want to crank the hell out of the bbl nut tho.
The shitty thing is I dont have a torque wrench. I need to get one soon cuz I could use one right about now.
What to do? (I know, get a torque wrench! I know, I know)

 

[deadly0311]

Re: AR-15 bbl install quick question

crank it down back it off, do this a couple times and then tighten it down then go to the next hole. Make sure to use some white lithium grease or anti seize

 

[Eagle1899]

Re: AR-15 bbl install quick question

You don't need a torque wrench, as deadly 0311 said get it tight and line the hole up best. All the upper does is hold everything, the bolt locks into the barrel. That where the pressure takes place. I use moly grease fom Honda ( the motorcycle one) It fits the the bill (Mil-Spec blah, blah blah and all that....)

 

[exhogflyer]

Re: AR-15 bbl install quick question

You really do need a torque wrench...tight to one person may not be to another.That said,hand tighten and loosen the nut 3-4 times( make sure you've moly lubed the threads).Now, with a torque wrench tighten the nut to 35 ft/lbs.Next,tighten it until the next hole lines up with the hole in the upper.This may be anywhere from 35-55 ft/lbs.Do not be overly concerned about the final torque as long as it lines up to the NEXT hole.NOT tight enuff can result in the handguard turning and binding up the whole shittin' mess....

 

[Outsydlooknin75]

Re: AR-15 bbl install quick question

Mil Spec is 30 to 80 ft lbs.

Like has been said ... put it on and off a couple three four times then tighted to 30 ft lbs, and then go till the next hole lines up.

 

[sobrbiker883]

Re: AR-15 bbl install quick question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: deadly0311</div><div class="ubbcode-body">crank it down back it off, do this a couple times and then tighten it down then go to the next hole. Make sure to use some white lithium grease or anti seize </div></div>

Yup.

I've yet to see one a)torque to the proper value and be lined up with the gas tube hole correctly, or b)come unscrewed when tightened by hand (not by a 6 year old gear "by hand", but tight) then wrenched to the next hole.