Dave: it the 2 3/4 marked gun a D grade? The pattern looks like "Legia P."

re: "declared sound" means the bore examined with a bore scope and with careful measurements of the wall thickness at the end of chamber, 3", 6", 9", 12" from the breech, 9" from the muzzle, the MWT measurement and location thereof, and those measurements documented in a written report; by someone with the interest, expertise and equipment to properly evaluate the barrels.
MWT alone is NOT an adequate evaluation.

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