I did it and am pleased with the results on my 1879 Parker D2. When I get it all back together I'll post pictures. After realizing my water was too acidic (hard) I went to distilled. Today I etched after 5 rust cycles and 4 carding cycles over a period of 3 days. The surface was a nice deep black. I brushed on the etchant and the contrast started popping out. When I thought it had gone far enough I washed it down with the hose - mistake. Almost as soon as I did that my barrels started turning GREEN. I realized that it was my well water and soaked them with distlled and etched again quickly. The etchant removed the green, then I covered the barrels with baking soda to stop the reaction. They have turned a bit darker, but still have nice contrast. I figure the finish will wear-in nicely and a perfect redo would look a bit out of place on a 130 year old gun. This was like baking a cake over 3 days, you really have to be vigilant and pay attention to the process. I have another set I'll start again soon. These barrels started with no finish at all and although I know what parker D2 looks like it was fun to watch the pattern pop out. Thanks again to you guys who share your hard-earned knowledge.
