I've been trying to discover what Browning's Silver Nitride finish is for a while, and curious about what other mfgr's are doing for coin finish. I think I have some reliable answers.
Beretta's coin finish is electoless nickel - Rich Cole
Kolar's coin finish is also EN - Doug Braker, former head gunsmith at Kolar
Browning's process for Citoris is Nitriding, aka nitrocauberizing - Doug Braker
Nitriding details Knowledge is good - I wanted to reblue my tarnished Citori but couldn't get the dope on what the 'plating' was. I thought it was EN, but EN stripper had no effect on the triggerguard that I tested. Now I find the 'plating' isn't plating but a special surface hardening. Clearly not something I want to remove.
Doug Braker said at the end of the nitriding process the pieces are brownish and tarnished. Then the pieces are carefully buffed to the bright finish, and that sometimes tarnish spots are a result of over buffing in some areas.
Thread on SW with info
