A few days ago I finished my 1st build.  I had some CRC brake and caliper grease laying around so I used that to grease my barrel nut and extension.  Today I realized that CRC grease contained Moly, PTFE, and Graphite.  It is said that grease containing Graphite are not recommended.  Do I need to take it apart and redo everything? Or will it be OK.

I'd strip it personally... Only takes a few minutes.

From the internet:

Graphite is not corrosive in itself towards aluminum, but in the presence of chloride ions (such as from sea-water or marine atmosphere) it can cause galvanic (bimetallic) corrosion to occur. The anodizing will however prevent the chloride ions from reaching the metal substrate for a long time - perhaps several years.

I wouldn't worry about it.

However, you are going to make the purists cry if you don't change it to the Aeroshell stuff.

I did a lil experiment on this a year ago it's in archives you will be fine. If you ever take it apart though use Aeroshell or Valvoline with moly to redo it.

Graphite is known to be problematic with aluminum.
Could be you would never have a problem.
It may be a PITA to redo it, but it is simply not that difficult.
I am one of the ones who uses a grease certified to meet the mil-spec.

Agree 1000%, and I don't even give a rat about Aeroshell.
Reading the above, what I hear is a  story of a known defect in workmanship that could lead to dissimilar metal corrosion in a critical area.
There are already too many potential UNknown defects with parts you can't make yourself, but you gotta just buy reputable stuff, mitigate the risks with best practices where you can and go with it.
I'd be willing to shoot OP's rifle all day long TODAY, but not three years from now.
There's always a risk / reward / effort / effect calculation in high-risk activities.
My personal safety algorithm returns the answer "Not on my rifle" for this one.

If not using the right lubricant on the nose threads of the upper and barrel nut creates a highly risky issue in just a few years, how much so the steel studs on your bearing hubs holding those nice expensive aluminum forged wheels?

Nobody does whiz about protecting them, or even servicing them beyond putting new rubber on the rims about 50k miles down the road. And those studs live in a nasty mix of road salt, engine drippings, and whatever precipitates from the sky or back of a cattle truck when on the road. For years at a time.

I've heard the purists mention it before, and then, I see pics of original M16 - nothings still being used by Montagnards in Vietnam . They were handed the rifle by a Special Forces sergeant before anyone knew we were actually crossing the border and pulling missions in North Vietnam. That M16 hasn't failed yet, and it's 40 years old.

Anybody really worried about corrosion and dissimilar metals in direct contact under a lot of heat needs to check their wheel hub and lug studs to see what they are worried about. Over the road trucks run 100,000 miles a year and lug stud grease isn't even heavily marketed. But we get the same old story about Aeroshell all the time.

Somebody please refer to the TM spec and show us what level of Support is supposed the check the grease under the barrel nut, and how many thousands of rounds it can go?

Don't forget edition and page number.

I've never seen that page in the manual either, but I HAVE seen the substructure of a 747 during a D check under where the head and galley used to live. So I'll just use some real easy to find non-graphite grease whenever I R&R the barrel on my AR('s) and THEN not worry about the parts I can't control with reasonable effort; Maybe leave 'em to a Montagnard in my will. ...I'll let you know how the running gear on my truck is doing once it's fired off 10,000 rounds or so of 5.56. Can you say AaaaaaaMen brother?  

Auto manufactures and mechanics have been using anti seize on steel spark plugs threaded in to aluminum cylinder heads for a long time. They also use it on oxygen sensor threads where you want to keep corrosion from happening in an extremely high heat environment. Id be more concerned with heat vs salt water.  

Areoshell 33 has a temp range from -73 to 121 deg C. or -100 to 250 deg F.

If this is the grease you used then its good from -34 to 315 deg C. or -30 to 600 deg F.
http://crcindustries.com/auto/?s=05351

Last time I had my Colt's barrel off, I used a mixture of moly grease and that silver colored anti-seize lube to reassemble it.

Should I be worrying about the barrel falling off?  

Some people would lead you to believe that it already has.

how much aeroshell do you guys use? I just dab my finger in it and wipe a little all the way around the front few receiver threads...
are MY barrels gonna fall off?

I use Royal Purple High Temp synthetic grease. It's FREE from work and good to 600 degrees.

so you stole a dab of grease you heathen!!





 

No. I stole a whole tube... With my bosses permission. I am gonna help him build a rifle so it's all good. His son makes these awesome box things that hang on the wall to put your guns in. Looks like a poster when closed. Opens up to reveal gun goodies

Got some free time today, went ahead and took the rifle apart, cleaned the old grease off with brake cleaner then used Mobil 1 grease on the barrel nut and extension.  Put everything back together, all fine and dandy.  Still waiting for my go and no go gauges.

Mixing lubes is not recommended; some are incompatible and create undesirable compounds when mixed.
Most anti-seize lubes contain graphite; which is definitely not recommended for AR’s.
No one can say you will have a problem, but you may have set yourself up for trouble in the long term or under the right conditions.

Oh my gosh, a drop of grease is going to ruin your gun?   Hogwash.   Use anything you have, you won't be taking it apart every week, probably never.

Hell I use the Mobil 1 grease on everything and for every reason.  Never had a problem and don't expect to.

I make sure all threads have a good coat also the area where the nut bears against the BE.
Too little lube may allow galling which could have long term consequences.

LOL, ain't it the truth?

V

X2 I find it very humorous all this none sense about the various lubricants one being better than the other. FWIW not all anti seize products contain graphite. I use a product by the name of NEVER-SEEZ, it is a pure nickel anti seize. Protects up to 2400 degrees. Made by Bostik and is well known in the petro chemical industry.

V