To the finish line!!

I know, I know, I haven't posted in a bit. But see, I'm better at being a Gear Guy than I am at waxing politic. So here's a gear post for you.

Background first. I snagged twenty-two (that's 22...) HK-91 steel mags off of GunBroker a couple months back for cheap. They were advertised as having "minor surface rust". I figured, what the heck, a little elbow grease and they'll be as good as new. I posted the winning bid at $42 and they appeared on my doorstep about a week later. Well, lemme' tell ya', minor surface rust, my ass!! They were nasty!! Now I had a decision to make: toss them or continue throwing money at the problem. Being that I am The Cabinet Man, throwing good money after bad has never been reason to stop while I'm ahead. Now, I've never done anything like this before -- never even held an airbush -- so this was uncharted territory for TCM.

So, I had the local headstone/memorial shop sandblast the buggers inside and out for $50. Then I ordered two kinds of finish: Lauer Weaponry's DuraCoat "Black Oxide" and Brownells' Teflon/Moly Oven Cure "Dark Park Gray". Not knowing how much would be required, I ordered a pint (16 ozs) of each. I also ordered an airbrush kit from Lauer that included a 1/4"-to-1/8" adapter so that I could use my air compressor for this task.

When back from the sand blaster, the mags had a nice gritty surface. They were so clean, they were silver colored!! I degreased them with acetone and then used a new toothbrush and compressed air to get rid of the cotton fibers left behind from the cleaning rags. I connected all of the airbrush goodies and was ready to go. (NB: the "instructions" -- and I use that term loosely -- for the airbrush were non-existant. I had to figger' the whole thing out myself. Not impossible mind you, but it didn't leave me with warm-fuzzies. Remember: newbie here...) I cranked down the line pressure off the tank to 45 PSI, pulled on some latex gloves, and was ready to go.

Brownells first.

The directions on the can specify that the metal to be sprayed should be warmed to ~100°F. To do that, I just laid them on a piece of plastic sheeting in the driveway for a few minutes. It worked great. I sprayed on two coats about 1/2-hour apart. The finish dries very quickly to the touch. In the case of bare steel, it was a matter of seconds (literally!!) until the freshly sprayed mag could be handled. After letting the second coat dry another 1/2-hour, I put them in the oven at 300°F for -- you guessed it!! -- a 1/2-hour. And that was that.

Now here are the negative details. First, there is no indication on the Brownells can of what to use for cleanup. Nothing I tried worked. Acetone, kerosene, mineral spirits did nothing. I finally disassembled the airbrush and scraped it clean with rags and pipe cleaners. I got it cleared-out enough to use later with the DuraCoat. Second, since the Teflon/Moly stuff dries so quickly it was tough to keep the airbrush clean and running. I was constantly fussing with the flow nozzle just to keep it clear. Third, the baking process is very stinky. Make sure you have a way to properly ventilate. I opened all the windows and ran the attic fan the second I smelled chemicals. There's a slight lingering odor but not much.

The good. The Teflon/Moly goes on very smooth and even. It's easy product to work with, needing no hardener or reducer. The color is a perfect match to the gray parkerizing I've seen on mil guns. As far as I'm concerned, the Brownells Teflon/Moly is quite idiot proof. (Thank God...) I used just over 1/2 the can of finish (~8 oz) for eleven (11) magazines inside and out.

DuraCoat next.

DuraCoat has no special requirements for preheating the item to be sprayed. Unlike the Brownells stuff, DuraCoat comes with a reasonably clear set of instructions. (It wasn't until I read them that I discovered the need for their reducer for clean-up. I went back to the Lauer site and it does state this, but it's not obvious...) The DuraCoat finish comes with a small bottle of hardener that needs to be mixed at a 1:12 ratio (hardener:finish). Throughout the DuraCoat phase, I mixed the hardener:finish in the color bottle a few tablespoons at a time. Not so good for consistency but it was all I had. Using the DuraCoat proved to be quite a challenge.

First, the DuraCoat is much more like a paint than the Teflon/Moly. It sprays on OK but remains wet for almost a 1/2-hour. This slow drying process made it difficult to spray the entire mag -- inside and out -- in one pass. It's also a very "sticky" finish. After the first couple of magazines, my gloves would stick to everything: the mags, the sprayer, the drop sheets. By the time I finished the eleventh mag, the airbrush was a sticky, globbing mess and my gloves were useless. It was very frustrating.

I also had trouble with paint "blobs" from the airbrush. I don't know much about them so I'm not sure if this was a "feature" of the DuraCoat or of the airbrush. (You can see one of the blobs in the center of the mag pictured below. This is actually one of the minor blobs. There are worse...)

One thing the DuraCoat does have going for it is that "a little goes a long way". I used very little product, less than half what I did for the Teflon/Moly. I also got the sense that a second coat wasn't needed. I still applied two coats to the feed lips and the areas that will contact the rifle (basically the upper third of the mag). Perhaps someone more skilled in such things would have put on two thin coats but my setup wasn't working well enough for me to do that. In hindsight, perhaps a bit of reducer in the mix might have helped with the blobs. I dunno'...

So here is the final result, DuraCoat on the left, Teflon/Moly on the right:

In my opinion -- at least for this application -- I would definitely choose Brownells Teflon/Moly over the DuraCoat. Sure, I had to hassle over the airbrush clogging while using the Teflon/Moly but it produced a much smoother, more even finish. And it was just plain easier to work with. Only time will tell which will wear better. In hindsight (#2), I should have experimented with just a couple of mags for each finish. That way, I'd have 20 mags in Teflon/Moly rather than just 11. Maybe DuraCoat works for other folks (those with better equipment?? with more patience?? with actual training??) but it didn't work so well for me. YMMV...

Thumbs up, Brownells Teflon/Moly Oven Cure!!


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