.[/quote]

Who offers the industrial black chrome finish for firearms?[/quote]

Marker machine in Ohio, This company chrome plates over nickle http://arlingtonplating.com/capabilities/black-chrome-plating/ another: http://www.olymco.com/black-chrome.aspx Bends PVD plating looks interesting and may reduce chipping that can happen with the nickle process. https://www.bendplating.com/black-chrome-vs-black-pvd/

I have only seen work by Marker Machine Co.this was on a number of Charles Askins Rifles, he thought highly of it. Not sure if they are still in operation, they were about ten years ago.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli