Tightening barrel nut

[EasyEJL]

So last night I went to install my barrel nut, the custom one that came with the MRF rails from Troy. The problem I ran into was that torqued to 30lbs the "points" on the nut where the wrench connects blocked the gas tube hole on the receiver on the left side, and raising the torque to 50 only made it worse, closer to the right side but just past center. In the end after going back and forth a bunch, I left it torqued to 30 and was just able to get the gas tube through. Is that ok/normal?

[Robocop1051]

You should put your barrel nut on and off 2 or 3 times before you really lock it down. The metal needs to stretch like a pair of jeans.

It's also ok to hit the threads with anti-seizing goop before final install.

[EasyEJL]

I just backed it off some and retightened 5 or 6 times. took it off entirely only once.

[Rsquared]

Like Robo said too. I use the "coppery" type of anti-sieze compund. Not alot.....just a light coating. BUT, wait until you're ready to try and lock it down before you apply the stuff. You don't want that poop on your hands. It won't hurt you.....but the only thing that really takes it off completely is time.

Edited March 18, 2013 by Rsquared

[StainTrain]

My MI Gen2 on one of my ARs was a tightening/loosening fiasco. I used enough moly grease to shove a suburban through a keyhole.

[98Z5V]

TIghten, loosen, tighten, loosen, tighten, loosen, tighten, loosen - you'll hit it.  If the barrel nut and the threads on the upper receiver are NOT lubed, you'l just make it harder on yourself. 

 

The torque spec is 30~80lb/ft.  Somewhere between 30 and 80, you'll hit it.  Don't try it with dry threads. You'll gall the poop out of everything.

[EasyEJL]

Yeah, I put a nice synthetic grease on it. I'll take the gas block off and try some more then :)

[Gray05]

I emailed SI Defense (they manufactured my upper receiver) and asked for their input on what to put on the threads when installing a barrel but.

"We use blue Loctite in some instances on the barrel nut."~excerpt from their response pertaining to this issue

This is different from anything I've read. Particularly what y'all have indicated here.

I planned on buying some ""coppery" type of anti-sieze compund", but now I'm inclined to use the blue loctite.

Looking for some input here. I'm pretty new to all this and I'm the wrong kind of engineer to know much about machined parts interacting.

[blue109]

Never used locktight, and don't think it's necessary. I've used anti seize that I have laying around for my spark plugs, and black lithium grease that was leftover from an engine build. Never came loose on it's own, and comes apart when I want it to.

[Robocop1051]

I used some lithium grease. I change my mind too often to use loctite

[washguy]

Nope on the locktite .......moly,lithium,plain ol bearing grease.....but not locktite....you have plenty of rotational space between 30 and 80 lbs of torque....I try and go for around 60 lbs or so....:) Wash

[Rsquared]

I use the "coppery" kind of anti-sieze that you mentioned. But a good grease would be just fine also.

[shibiwan]

Question - why would you need loctite when the gas tube already prevents the nut from turning? Seems silly to me.

[98Z5V]

Not all barrel nuts have hole in them for a gas tube to pass through - but that doesn't matter.  You NEVER need loc-tite on a barrel nut. 

 

No matter what.

[Toolndie7]

We used to take the silver anti-seize and gently brush it on a co workers keys that were silver. <lmao>  Holy Sh** by the time they noticed it was all over the freakin place.   But you didnt hear that from me.

[Gray05]

Very helpful responses. I've emailed SI back for more clarification on the matter. Loctite seems crazy to me. That was not what I was expecting at all.

I'll post back if they respond.

[Robocop1051]

We used to take the silver anti-seize and gently brush it on a co workers keys that were silver. <lmao> Holy Sh** by the time they noticed it was all over the freakin place. But you didnt hear that from me.

Cops do the same thing with fingerprinting dust. It's actually magnetic and will attach to everything, like fine graphite.

[Gray05]

Cops do the same thing with fingerprinting dust. It's actually magnetic and will attach to everything, like fine graphite.

Sounds like I'm in the wrong line of work. Pranks are nonexistent at my workplace. Probably a quick way to get fired. Maybe it's worth a try anyway...

[Robocop1051]

Best work prank is shutting off the toilet water, then giving it one last flush. The next guy drops a log on a dry bowl.

Once rigged the stall door so it wouldn't stay shut. Had to hold it closed while poopin.

Best ever... refilled a purell bottle (hand sanitizer) with ky jelly. Watch with glee as they try to rub that shiit in. Lol

All harmless fun.

[unforgiven]

There was this guy was a big musclehead goes to take a dump and one of the guys put's ammonia on the floor.His face was as red as his a$$.

[Toolndie7]

Ok ok I think we need to start an official work place prank and make it a sticky ::)

[survivalshop]

Manufacturers use a loctite on Gas blocks & gas key screws( instead of straking them) also .The whole design from Mr. Stoners &  crew was that the gas tube was to keep the barrel nut from loosening & have some find of way for a tool to attach it , making a barrel nut that is not configured to allow that feature ,may indeed some type of lock set to keep if from backing off.

 

My PRI Muzzle Brake kept loosening after a day at the range & after calling them , they said to use loctite & I used the Blue removable & it has not loosened since & that was a few years ago, so it may have some merit .

[shibiwan]

In one of my past jobs, I put up official-looking made-up name tags on empty office cubicles: Ho Lin Wan, Hoo Fung Poo, Goh Fook Yue, Sze Yew Fatt...... etc.

 

Upper management walked by and asked if I'd met the "new" guys yet.....which was quickly followed by muffled giggles from my guys in the next cubes over.

 

(Fun stuff you can do when you have a vinyl cutter)

Edited March 6, 2014 by shibiwan

[unforgiven]

^^^^ Love it. <laughs>  <lmao>

[Zebra644]

TIghten, loosen, tighten, loosen, tighten, loosen, tighten, loosen - you'll hit it.  If the barrel nut and the threads on the upper receiver are NOT lubed, you'l just make it harder on yourself. 

 

The torque spec is 30~80lb/ft.  Somewhere between 30 and 80, you'll hit it.  Don't try it with dry threads. You'll gall the poop out of everything.

 

EXACTLY or you have the same issue I did with my recent install. Even Noveske on the NSR Rail, states to use a grease on the barrel nut threads and you may need to tighten loosen.Thier brand specific Torque specs are 40-80 lbs. Mine was done at like 35 and after 100 rnds of frustration it came loose. Redone to 80 and wnd Ill be at the range this weekend. I'll post thr results on my other thread as not to thread jack ^-^

Edited March 6, 2014 by Zebra644