Howdy all!
I “antiqued” a Uberti 1860 Army I had. I removed the blued parts (barrel and cylinder) and wrapped them in paper towels soaked with white vinegar. After a few minutes the bluing was removed and left behind a faded mottled pattern. I thoroughly rinsed the parts with water, dried them well and gave them a good coating of Ballistol. I’ve never had any rust issues so far.