So here is a potentially silly question, but I will never know if I don't ask. When a gun that was made in the 1970's was submitted for proof, and was marked with .729 by the proof house, was that the EXACT measurement of the bores at that time? Or by marking it with .729, does that mean it falls within the 12 gauge rules that it must be in the .729-.739 range to maintain it proof.
The reason I am asking, is that I am looking a 12 guage that is marked .729, but has the following measurements: .732 right, .733 left and walls .028 right, .030 left.
While it is still within proof with those measurements, the wrench in this scenario is that this gun was proofed at 4 tons, and is a heavy waterfowler. It would be used with loads in the 10,000-11,000 psi range.
If this was a 6 1/2 lb, 1 1/8 oz proofed game gun there wouldn't be an issue, but my first instinct (which is usually the correct one) would be to pass on this one due to the wall thickness measurements. I guess I would expect a gun like this to measure .032+. Am I over thinking this, or would anyone else have issues with this one?
