Confusing assembly instructions for AR-15

[devils4ever]

Hi all,

I am finally getting everything together for my target AR-15 build. I've been reading websites, watching videos on how to do the assembly as well as reading, "The AR-15 Complete Assembly Guide" by Walt Kuleck. I've seen so many conflicting pieces of information that I'm totally confused.

Do I use grease on the barrel install or anti-seize compound or blue Loctite?

Same for the buffer tube. I've seen all three mentioned.

If grease, what type? I've seen CLP, moly lithium grease, moly disulfide grease, Tetra grease, etc recommended.

I have some Valvoline moly disulfide grease and Tetra grease.

I've also seen recommendations to grease the buffer spring and to not do it. Argh!

If it matters, I'm using an Anderson lower and Spikes upper with a Shilen 20" SS barrel and Spikes LPK.

TIA.

 

[HOOfan_1]

Don't use loctite...

the mil spec grease to use where the barrel nut and upper receiver meets is moly grease...you don't want anything with graphite in it.

this stuff is Mil Spec
http://www.amazon.com/AeroShell-Ext..._1?s=automotive&ie=UTF8&qid=1410965624&sr=1-1

You don't really need grease on the receiver extension because where it screws into the lower receiver is an aluminum-aluminum joint, as opposed to steel-aluminum on the barrel nut. I used it on that anyway.

by the way moly stands for molybdenum disulfide and the lithium is just the base ingredient in the grease.

 

[MachIVshooter]

Use some kind of high pressure grease on the barrel nut. Plain old high temp bearing grease is fine. Corrosion prevention is a fringe benefit; the actual purpose is as a lubricant to prevent galling, thus protecting the aluminum threads and allowing the proper amount of torque to be applied. Same reason we put oil on cylinder head bolts.

No need to use anything on the receiver extension, although thread locking compound on the jam nut would be an alternative to staking the nut.

 

[devils4ever]

HOOfan_1: The Kuleck book recommends blue Loctite on the receiver extension. Other places I've look at, don't use anything. Do I really need that Mil spec grease? Or, is the grease I have okay? I'll buy if I need it, but I'll probably never use it again.

MachIVshooter: The book doesn't mention staking the nut on the receiver extension.

See what I mean, this is all contradictory and confusing! :banghead:

 

[1KPerDay]

Some people put blue loc-tite on the barrel extension to help it lock more solidly into the upper receiver. Supposedly helps accuracy. If you plan on swapping barrels with any degree of frequency, don't use it. Grease is optional IMO. It's a slip-fit and grease isn't going to do anything important there IMO.

The buffer tube? Use some type of anti-seize on the threads, IMO. And on the threads of the barrel nut.

There's contradictory info because there are a lot of different ways of doing it and everyone and his dog is assembling ARs.

Bottom line is if you don't use any lube or antisieze or loc-tite you will probably have zero problems.

 

[highpower]

Avoid trying to over think and over complicate the process.

As an experiment, I have assembled the barrel to the receiver using Loctite, grease and nothing at all. So far after 25 years I have noticed no difference in regards to the barrels loosening up. Out of the twenty or so AR's that I have put together all the barrels have stayed in place regardless of the method used.

I have never heard of staking the barrel extension in place. Once you have torqued it down so the gas tube lines up, they pretty much stay there unless you take it apart. For that matter, once the castle nut is torqued in place on the buffer tube they should stay put also. I do stake the castle nut though for piece of mind.

Assembling an AR in not rocket surgery. They are easy to put together and it should take you no more than one hour to from start to finish.

 

[MistWolf]

ARs are very easy to assemble- until they're not. Use lube on the barrel nut. Aeroshell 33 is the approved grease although you can substitute any grease or anti-seize that does not have graphite or copper in it. There are some very good reasons why you should lube the threads and no good reasons why you should not. DO NOT use Loctite on the barrel nut threads unless you want to make removing it at a later date very difficult. Using Loctite where the barrel extension goes into the upper is supposed to fill any voids and keep the barrel from shifting. It's optional and if you do this, use Green Loctite. Look up the approved method of torquing the barrel nut. They are very specific.

You can use a little thread lube on the receiver extension and castlenut. It's not as important as the barrel nut. Unless you are very experienced with torquing the castlenut, stake it when finished. Don't use Loctite unless you want to make removing the castlenut at a later date very difficult. Keep an eye on the RE as you're torquing because you want to orient it so the stock is straight. Use the right tools and a vise

 

[MachIVshooter]

I have never heard of staking the barrel extension in place. once you have torqued it down so the gas tube lines up, they pretty much stay there unless you take it apart. For that matter, once the castle nut is torqued in place on the buffer tube they should stay put also. I do stake the castle nut though for piece of mind.

Receiver extension (buffer tube) jam nut, not barrel nut.

 

[highpower]

Receiver extension (buffer tube) jam nut, not barrel nut.

Okay Mom....

 

[gotigers]

Nothing but molly grease on a barrel nut.

Just torque the castle nut on the buffer tube/extension. I've never had a castle nut back off.

I don't use lock tite for either.

 

[MachIVshooter]

Okay Mom....

Inappropriate & juvenile response.

You misunderstood, I clarified. Simple, and does not beg a snide remark.

 

[highpower]

I clarified. Simple, and does not beg a snide remark.

Actually my post, while maybe not totally verbally exact, really didn't need clarifying.

I was trying more for sarcasm rather than snide. I guess I'll have to work on being more clear about that.

 

[MagnumWill]

Getting back on track....

Be careful if you decide to install Loctite in the buffer tube extension. If you put too much on, you have the potential of getting it in the hole for the buffer retainer, and when you go to disassemble the rifle at some point, you'll find you can't get the buffer out because the retainer is frozen in place. Not saying you can't finagle with it, but I don't see any real benefit. I've put all three of my AR's together without Loctite or grease, just a small touch of anti-seize where appropriate.

 

[devils4ever]

I can't tell which auto greases have graphite or copper in them. So, I found someone on eBay selling small quantities of AeroShell 33MS. I figure I'll use the recommended stuff to be safe.

 

[HOOfan_1]

I can't tell which auto greases have graphite or copper in them. So, I found someone on eBay selling small quantities of AeroShell 33MS. I figure I'll use the recommended stuff to be safe.

Umbrella Corp sells it too.$3.00 for such a small amount, that you may as well pay the $17 bucks the entire tube costs.