coating an AR15 gas block area

[BOLTED]

Thoughts seem to be all over the internet board on this, but here is my dilemma.

I bought an overrun lilja 223 CM barrel that was never coated with anything. I plan to use air dry Cerakote on it, but I don't feel like I should coat the machined area under the gas block. I can keep the coating fairly thin, but I don't want to have a tolerance issue now, or a rust issue later. I could do something like cold blueing on the gas block area, or I could just leave it bare steel with some heavy grease under the block.

Anyone have any real world experience with this, or some thoughts and ideas?

Thanks,

Dave

 

[jelenko]

While I go through AR barrels in a season or less, I just put a light coat of oil on them.
There's either no rust or the faintest hints that are easily removed.

Even surface rust on the outside isn't going to affect the performance.

I also don't need to take the rifle out when it's raining.

 

[DaveTooley]

Just plug the holes and coat the barrel and block.

 

[Hino895]

Check the tolerance with the gas block.
I do Cerakote professionally and when I do a barrel I tape off that area with 1” painters tape otherwise you will have to pound it on with a brass mallet.

 

[DaveTooley]

It can be coated and then a slight polish to fit. That will leave a slight residual layer .

 

[tobnpr]

I agree with above.
Colors like Graphite Black cover completely in a single, light pass.
Some others, tan/brown shades in my experience among some others- require multiple passes, sometimes three or more to get complete coverage with no bleed through or appearance of "holidays". Those would be more problematic due to the thicker DFT of the coating.

 

[Dusty Stevens]

Id coat it and polish it to fit like dave says.

 

[BOLTED]

Thanks for the input.

That's all I need, just a thin flat coat that creates a minimal non porous barrier.

Any thoughts on the cold bluing? I did an old shotgun barrel and it came out nice. Seems moisture resistant, and I can definitely polish it down.

If I had bought this barrel fully finished rather than in the white, would it have had a coating applied to the gas block surface? All my AR type barrels are stainless, so I don't have one to compare to.