I have an Ohio Case Color gun and it is definitley bone charcoal. Did they revamp their process and are now doing cyanide?

I don't know Dave. I know they did cyanide process.

Interestingly, I believe its Turnbull's web site, cyanide color case hardening can be made to be almost imperceptible from bone charcoal colors. So these gaudy colors that some do not like do not have to be that way and the color result is much dependent upon the technique of the cyanide process technician. Don't ask me how its done, maybe a mix of artistry and magic. I have also seen worn cyanide colors that are imperceptible from worn bone charcoal case colors.

Those case colors look just about perfect for a Savage-era Fox-Sterlingworth.