I posted this a while back
Black Oxide Test
I decide to do a test comparing 2 different black oxide treatments I'll compare Brownells Oxpho-Blue to Caswell Plating's cold black oxide concentrate. Product: Brownells Oxpho-Blue 4 oz. U.S. Cost from Amazon $34.54 $8.58/ U.S .oz. (taxes and shipping extra) Caswell Plating Black Oxide...
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