I used engine block/header high temperture paint to paint my stainless barrel on my NM M1A a "tactical" black satin. In the five years since the paint hasn't burnt off nor been scratched.

That paint will stand 1200 degrees which is a bit more than your barrel will stand before becoming a limp noodle.

You've got to clean the steel 100% clean. I used a dry cleaning solvent that removed the oil completely. You can't handle the rifle after cleaning and before painting with your hands to avoid getting your bodies oil on the steel.

Wal Mart's got military flat spray enamels in the paint dept. I redid my FAL with it, looks dark dark gray, almost like phosphate, I tried torture testing itonce it set. I couldn't scratch it off with twigs, fingernails, ect. Bore scrubber don't eat it like the other paints either. I tried some on a scrap steel plate, and the propane torch took FOREVER to get it to bubble. I doubt I'll get my bbl that hot
_______________________________________________Got F.A.L.?

Brownells Aluma Hyde II is what you want. It looks more like a finish itself than a paint when its cured. Holds up well and seems pretty impervious to solvents. Comes in a couple of different colors. I've done my SAR's metal in flat black, looks like black park, a couple of knife handles, and a scope, and some M16A1 stocks in OD, with real good results. Takes a little prep, degreasing is important(as with any paint) and it requires about a week to fully cure, but you can put it back together in 24 hours, if your impatient(like me)just be careful though.

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