Over in the For Sale/Trade  forum under the subject:

"Withdrawn due to no interest. New C Sharps 1874" 

there's a discussion about a picante sauce finish.  Rather than continue it there (sort of off-topic at this point) I thought I'd ask this here:

How durable is this picante sauce finish compared to French Grey?

I have a Low Wall with a French Grey receiver and the finish is getting thin.

The pic below is from that discussion and the followup poster said:

Degrease, spoon the sauce on and let it set for 20 minutes.   
The  vegetable pieces make the mottled shapes and the vinegar causes the dark uneven staining. 
Rinse and oil then reassemble

I like the looks of this and it's within my gunsmithing skill set.