Hey Retro guys, I'm mainly a Mk12 guy but seeing as they were built on M16A1s that were headed to DRMO, I had a question for you guys.

When M16A1s were refurbished or rebuilt at the arsenals, were they recoated or refinished black with anything other than anodizing? I ask because at least one Mk12 Mod 1 lower from the SMGLee dump has a lower that seems to be almost satin with an "orange peel" look to it, like one might see due to paint or some sort of coating.



Are my eyes just tricking me, is this just the lighting? Or did older lowers get a black sprayed finish of some kind when they were reworked during their lives? I'm curious in relation to building 80% lowers and doing Type II anodizing. I was wondering if after anodizing there was a "correct" or acceptable spray finish in case the anodize dye process goes south, or simply one that would replicate a refinished A1 as used for some of the Mk12s.

They refinished uppers in that coating also, I have a couple.

I don't know what it is, but I'd rather have it than LineX in a truck bed.

The texturing may be from the fact that the lowers were weathered enough to NEED re-coating or anodizing (due to exterior beat-up wear) but weren't sand-blasted or otherwise treated (with the exception of being cleaned-degreased).

A lot of lowers (and upper-lower sets for that matter) were kept in service a while just by being coated with solid dry film lubricant.

they dip them in tar and then that stuff is diamond hard!!!!!!

Knowing our luck it's probably asbestos based

That will put hair on you chest

Well, hopefully I get a serious reply at some point, all joking aside. Trying to sort options for "correct" lowers, especially for folks now in a position where they have 80% lowers and still want to anodize.

They had a couple different kinds of stuff they used at arsenal level.  Most of it is nearly impossible to remove without blasting and then still a beeech. Very little if any re-anodizing.

Initially they were dipped in a vat full of the stuff then hung to dry.  Dip one end then the other and hang up.  These are usually easy to spot because stuff will collect like a paint run on end hanging down.  

Think I've seen this process written in early armorers manual.  As time progressed I think stuff was different an application different and probably more like a spray epoxy paint and as already stated some simply used dry film lube per milspec.  I still have some of this laying around and I use it on magazines.  This will be the shiny grey graphite feeling stuff.  Think in theory the dry film lube is only supposed to be for touching up receivers but I've seen the whole thing done before.

Some of the earlier stuff was gritty for lack of better term but not the vat stuff.  It's more like blackish anodizing.  See the gritty stuff rather frequently in the govt re-pack receivers if seeing a govt re-pack receiver is frequently today.  hope this helps.

The dry film lube is a "unit level" item.

Anniston Army depot rebuilt guns (at least for the Army); The stuff was/is painted in a semi gloss paint. Still continues today.

I wondered if it was some type of paint as well. I have seen both lowers and upper have sections of finish peel and flake so I knew it was not anodizing. I remembered thinking, "surely they are not just painting the things with spray paint."

BTW, I heard the paint was an epoxy-based paint like appliance paint.

I've seen several examples of the USAF M16 to M16A2 conversions that has the lower receiver refinished.   Majority of these were done at the USAF Gunsmith shop at Lackland AFB.



Most of the USAF M16 to GAU/GUU-5/P conversions had an "ANAD 71" or Anniston Army Depot stamping on the magazine well.  I've seen several examples of these being refinished in a black finish.....

Thanks guys, I just fired off an email to the AAD public affairs office. We'll see if I can dig anything up.

do they still do this today with m4 carbines?

They used some type of coating that was designed to coat the inside of metal pipe.  It has a satin black type finish.  It is very smooth and slick.  It almost looks like the finish on frying pans.  It holds up real well.

My issued M4A1, converted from an M4, has some sort of epoxy feeling refinish over the left side of the magwell where the M4 rollmark was XX'd out and restamped M4A1, as well as the area where BURST was XX'd out and restamped AUTO. This was done here on post by a team of armorers sent to do the PIP. Not sure where they were from but they have been to several posts. The M4s which came back from Afghanistan recently had to be sent out for the PIP upgrades. I am curious if they come back with ANAD markings.

We have a handful of M4A1s which started out as FN M16A2s. Those markings were milled out and restamped in the same location, as opposed to XX'd out and stamped underneath the old markings.

Here is a picture of an H & R M16A1 converted to an A2.  All of the A1 conversions in my former unit were rebuilt at Anniston in 1996.  All of them had the slightly purple looking color on the refinished lower.  I have no idea what caused them to be this color, but they all were.  I have seen this color on many other rebuilds over the years.