For clarification, auction houses and dealers publish minimum wall thickness. So, the walls might measure over 30-40 thou in most areas but if there is a raised dent that has been cleaned out and a thin spot of 19 thou, the measurement given will be 19 thou.

Regarding the 7 thou proof pass. The gun was in an auction and was delivered asa n out of proof gun. It was cleaned up and re-proofed to make it legal to sell in tact.

Wall reduction tends to be either incremental as a result of lapping the entire bore to remove pits or spot located, where a dent has been removed or a bulge knocked back. The section behind the chokes going back for about 10 inches is the place where barrels are thinnest.

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