I have a couple of cans Brownells aerosol Gun-Kote.
The instructions say to, “pressure blast all parts that will be sprayed.”
I assume that means down to the bare metal.
Can I just spray it over bluing, parkerizing, or even paint for that matter?
Potential projects include AR rails, receivers, barrels, and handgun barrels, slides, and frames.
Parkerizing make a great base surface for coatings.
Anodizing makes a good substraight as long as it was not teflon coated.
Bluing on the other hand does not since the metal is polished and the blueing is just very thin surface salt rusting. (read your trying to make the paint stick to glass).
As for spraying over paint, it just depends on if the two are compatiable.