Anti-seize On barrel extension during assembly?

[WxWatcher]

So I'm finally assembling my AR tomorrow as I wait on my bolt. During assembly, is it beneficial or recommended to put some anti-seize on the extension so if I ever swap barrels it's not stuck in the reciever with carbon build up? Or does the extension get too hot for anti-seize?

The other thing is that my barrel (Rainier Arms match) fits really (really) tight into my upper receiver (Mega billet). Extension gets about half way in on it's own before some bit of force is needed to get it the rest of the way. Not sure how much force as I've not wanted to not be able to get it back out should anti-seize be recommended.

Thanks in advance for the feedback.

 

[-Nick-]

I just assembled my upper which is also a Mega billet with a Rainier Ultra-match and had the same issue with the fit being tight. I errr gently coerced the extension in with a rubber mallet. I was told by several people who's experience is greater than mine assembling AR's that it's not really necessary to use anti-seize, but I'm sure opinions on this are going to go both ways. Good luck on your build though!

 

[Dracozny]

They make high temp anti-seize such as silver or copper. it has been recommended by some smiths to use anti-seize on stainless barrels. other smiths just use an oil based lubricant on non stainless.

 

[M25BeastShooter]

I've always used what the Military uses High Temp Moly Grease been using it for 20 plus years. Worked great so far.

 

[Crapshot]

I don't see how it could hurt. I use it every time I screw on a new barrel with no obvious ill effects. That said I don't remember having a very difficult time getting a barrel out of a factory upper over 10 years old with 2500+ rounds threw it (we don't shoot enough I know).
I say use it especially if the extension is already a tight fit, not much tho

 

[matt2143]

I have beaten some AR-15's and AR-10's to hell and still could break em down to rebarrel. I found anti-seize for the threads of the barrel nut and keeping the extension dry in the receiver worked very well. I shot a lot suppressed and unsuppressed with very good results (nothing a rubber mallet tap couldn't break free).

 

[Crapshot]

I've always used what the Military uses High Temp Moly Grease been using it for 20 plus years. Worked great so far.

+1

I actually use engine assembly lube/grease with moly in it.

 

[ORD]

I have beaten some AR-15's and AR-10's to hell and still could break em down to rebarrel. I found anti-seize for the threads of the barrel nut and keeping the extension dry in the receiver worked very well. I shot a lot suppressed and unsuppressed with very good results (nothing a rubber mallet tap couldn't break free).

+1 on all of this!!

Just be cautious of any anti-seize with graphite in it because: graphite + aluminum + intro of any H20 source = BAD!

 

[matt2143]

I am a mechanic and never knew anything about graphite+alu+H20 = BAD..... Learn something new every day.

However I do use the Moly assembly lube for engine cylinder head bolts for high torque without binding and have used anti-seize on the same application and hundreds of others. Honestly anti-seize is messier but it flat out lasts. Normally I use the silver version from Permatex but even my Thunder Beast can came with the gold version gobbed in the threads. Shit just works.

I have seen some other stuff used and the key is to utilize a medium that prevents not only galling on install but is tough enough to maintain its properties upon removal to ensure the threads stay on the upper....

 

[sr15match]

I had my new KAC MOD1 apart recently and there was a light coat of oil on the extension. It came apart and went together nicely, snug but nice.

Works for me.