1905
Try using some foaming type bore cleaner like Wipe Out or Gunslick Foaming Bore Cleaner. The rifling does not look too bad, and a good cleaning should make a good improvement. If you make one application, run some patches through the bore, then loosen any further crud with a bore brush, then patches, then another shot of bore cleaner followed by patches, it is surprising just what gunk does come out, and what condition of the bore is really in. Some really bad ones come out not too bad, and definitely shootable.
If you can find someone who collects stamps, or a store that sells items for the stamp collectors, there is a light that is used to detect watermarks. Because wood compresses when stamped, it is sometimes possible to bring out the lettering by shining one of these lights on the stock.
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