Gunsmithing Easy fix for darkening/blackening nickel-plated steel?

Veer_G

Beware of the Dildópony!
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Minuteman
Jun 15, 2008
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I was expecting a matte-black trigger, and wound up with nickeled steel. Outside of a swap, what's an easy fix, if any? I'm not terribly worried about æsthetics, mind you.
 
I've got stuff to blacken nickel silver (for fly rod hardware) but I've never tested it on nickel plated steel. I was hoping someone would respond with something for you.