Why are blue finishes more durable tha CC?
 

Why does rust blue on barrels generally hold up better to wear versus CC?? Do blued finishes penetrate deeper into the metal?? Why does blue on Parker lower grade trigger guards (Trojan, VH, PH etc.) wear so quickly??

As I understand it, the rusting of the barrels causes microscopic pitting allowing the bluing to lay deeper in the steel than if the surface was simply smooth.
Color case hardening creates a layer of carbon particles to adhere to the smooth surface of the steel. The hardness goes a few thousandths into the steel but the particles creating the color are only on the surface.





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Guards are nitre blued vs barrels are rust blued. Rust blue is more durable.

Brain: Thanks, is nitre blue faster and less costly process?

Another way of expressing it is that rusting bluing is achieved by applying multiple layers of rust which is carded off until the desired depth of blue is achieved. Case color is a pleasant side affect from the necessary process of casehardening and has very little durability unless the parts are externally lacquered. Nitre blue is another heat related process which has little durability and little depth but is inexpensive for manufacturers

In some ways CCH is more dureable. Even if the case coors are not visible anymore the protection remains. Not really what you were mening I know but i couldn't help myself.

Forgive me if I'm commenting beyond the intent of this thread but, I have yet to find a lacquer or, any other coating that can be applied in a manner that comes anywhere close to replicating the beauty of engraving upon bare metal.

Now, to topic - are there any manufacturers that rust blued trigger guards and other appointments, save screw-heads, in general practice? I'm 'guessing' Parker? The guards and SBP's on my PR's appear to have the soft glow of rust bluing.

Lacquer is clear and protects the CC to a point. Marlin used it on there L.C. Smiths and some rifles , Turnbull has used it, and Galazan has sold it. Oh you'll be able to see your engraving just fine if its used on an engraved gun, provided you don't choose a 5 yo to apply it. Perhaps Win. 21's, Tobin, and some Bakers used a hot blue on receivers and trigger guards but I doubt it was rust blue ------- to labor intensive.

All blued parts on (meriden) Parker guns other than the barrels were nitre blued. It is a fast process. Much more so than rust blue, but far less durable.

To my eye the application of a protective film brings forth a lack of third dimensional depth and that inconsistent depth of field takes away from the artistic realism of the scenes found in the Parker style of engraving. Parker engraving screams nostalgia in a manner that "takes you there" so to speak, to me. Perhaps I'm just a shade critical or, perhaps perfection is my curse but, somehow the engraved lines filled with "something" seems to detract.

Please, share the material that you use and, your technique.