I had the gun stripped, inspected, cleaned, and oiled at Turnbull Manufacturing Company. I spoke with their shop supervisor after he provided the barrel thickness measurements I requested. We discussed my options using the Lite [low pressure] loads made by RST for vintage double guns;
1 oz. 6800 psi
7/8 oz. 5800 psi
3/4 oz. 4800 psi
He stated "Any of those will be fine and safe to shoot."
Considering repeated assurances the gun is safe with the RST ammo I am leaving it as is - for this hunting season at least. I will definitely have it sleeved if I choose to sell it someday.
Just so I know for my own benefit: Are you stating the following:
1. Turnbull did your barrel work removing enough material to make one barrel .018" at 9" from the breech?
2. Are you also stating that Turnbull told you that a 16 bore gun is safe to shoot with the shell/pressure/loads above in a gun that IS .018" at 9" from the breech?
If no, please clarify as this ambiguity could devastate their credibility and their business. If yes, this information should devastate their credibility and their business!
And on a personal note, if they did tell you these things and perform the work I'd do ABC:
A. Ask for all your money back
B. Barring that, send a notice with the intent to follow suit.
C. If unsatisfied with their response, get a couple of experts to write you their analysis of the gun and litigate as you have a strong case. (they'd have defied every guideline of the industry and the proof benchmarks that are accepted in dozens of countries as to what "safe" is)