And DelGregos have used the cynanide process for their case coloring. To my limited knowledge they do not use bone charcoal.

Allen, Delgrego does not now, nor ever did any case hardening. It was always sent out.

And more recently the shop Del Grego sends his case coloring jobs to is using the bone-charcoal method from what I've seen.





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Delgrego uses Turnbull.

Like "fluid steel", "bone-charcoal" has become standard phraseology, when it is used to describe either the material, or the organic heat treat process. Both terms are used so often, they are automatically considered correct. Fact is, all steel was, at it's origin, fluid. 'Fluid' somehow got tossed into many peoples description of barrels other than composite, such as damascus. Maybe Sir Joseph Whitworth's process of forcing molten steel, under pressure, into ingot molds is the source.
Likewise 'Bone' got tossed into the name for a heat treat process which imparts a carbonaceous layer when steel reaches it's upper critical temperature.
Bone is simply one of the ingredients some used to add carbon, but many organic materials, high in carbon, are used.
Two of the most commonly used ingredients, used by Winchester Repeating Arms, and Colt Patent Firearms Mfg Co. were scraps of leather shoe soles, and horse hoof clippings. In fact, Colt didn't use bone,
per se, but coarsely ground bone, or, bone meal.

Who, in the collective opinion of our members, is best at replicating original Parker Brothers case colors?





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That’s as dangerous as politics and religion.
I can’t speak to the present day, but Brad was, in my opinion, the closest. I honestly believe today’s generation is trying to get too exotic with their packing recipes. I haven’t seen any of Doug Turnbull’s Parker work, but I sure don’t think old Oliver would be too pleased with what he does to an 1886 or ‘92 & ‘94

Dean, that truly is the "ten thousand dollar question". A few years ago I sent off a PHE 16 Gauge ejector gun with Parker Steel Barrels for a "complete restoration" to include new case colors. I will not say who did the job but he is well respected in this community. I saw several examples of his work and felt confident that the job would come out great. When I received the gun back I was literally sick to my stomach. The case colors were splotchy and clownish in nature. Perhaps it was the way that specific guns metal took the process, I do not know, but it was horrible. I quickly sold the gun and moved on. I will never have another gun case colored again.

Steve, all Parker hammerless receivers started life as a forging. Billings & Spencer, and later, Bourdon Forge made these for Parker and they would have been received in a 'normalized and tempered' state. The short answer is they are a very uniform hunk of metal.
The reason for pattern variation (The Good, The Bad, and the Just Plain Ugly) is entirely dependent on the process, but not the part itself. Poor packing of one receiver, using the same recipe as another, well packed receiver, will be so entirely different, one could easily assume they were done by different heat treaters. The random nature of all Parkers is due to the fact that no receiver can be packed the same with respect to orientation in the packing box, exact mixture of ground charcoal, and other carbon bearing organic materials, heating, and final quenching.
At Colt's, 4 SAA receivers would be packed in the same packing box, cover then compressed, and clamped. After the quench, no two parts would look exactly alike.

These both were case colored by Brad just prier to his passing.....I was satisfied but do they replicate original colors? I will leave that to you.