The Antiquity of French Gray Barrel Finish

[Cruzatte]

There was discussion on another thread about the antiquity of barrel finishes; blue, brown, bright, and French gray. I was wondering how far back French gray can be noted. Is it a nineteenth century fashion, or can it be dated to the eighteenth century? Are there any examples of French gray being used on fire arms from before let's say 1750?

 

[kje54]

There was discussion on another thread about the antiquity of barrel finishes; blue, brown, bright, and French gray. I was wondering how far back French gray can be noted. Is it a nineteenth century fashion, or can it be dated to the eighteenth century? Are there any examples of French gray being used on fire arms from before let's say 1750?

I've been doing some quick research and the only thing I can find are processes to French Grey gun metal but no history on it. The process is apparently to add muratic acid to the bluing solution which supposedly results in the final grey finish.

 

[dave_person]

Hi,
Real French gray finish is not what most folks are doing. They are simply graying the metal surface with an acid or tarnishing compound. Real French gray is done on highly polished case-hardened steel or iron surfaces. It probably evolved from the French "glass" finish of the early 1800s, which was hardened steel highly polished to a glass-like finish, which provided a fantastic background for the fine copperplate engraving style that became the fashion. However, shooters and hunters found it too shiny and the French then developed a way to dull it with mild acids that resulted in a very fine grained matte gray finish that still highlighted the engraving very well. Because of the case hardening requirements, I don't think it was applied to barrels just the other steel and iron components. I believe it is pretty much a 19th century fashion. I've read that boric acid is a good etchant to use because it is much safer than sulfuric or hydrochloric acid and being mild slowly produces a fine-grained matte finish.

dave

 

[Cruzatte]

Thanks, Dave. I knew I could count on you.