Bolt Finish

[Bruce McAskill]

I think the Du-lite finish is really not a bluing but closer to parkerizing then bluing. Just that the chemicals used turn the bolts into a blue/black color. A much more durable finish the rust bluing. Most collectors just say the bolts were blued and let it go at that.

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[Johnny Peppers]

I think the Du-lite finish is really not a bluing but closer to parkerizing then bluing. Just that the chemicals used turn the bolts into a blue/black color. A much more durable finish the rust bluing. Most collectors just say the bolts were blued and let it go at that.

I will have to disagree there. Du-Lite is a blue and not a phosphate finish. The early Remington Rand, Ithaca, and all the US&S 1911A1 pistols were Du-Lite blued over a sandblasted finish giving it a phosphate look due to the sandblasting, but the rare Singer 1911A1 had a highly polished Du-Lite blue finish. As specified by the military, Parkerizing was a Type II phosphate finish, and bluing is a Type III black oxide finish.
The old rust blue finish was slow and labor intensive, but one of the most durable blue finishes ever used.
Du-Lite bluing is still sold today.
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