Is either the rib or barrel marked L.C. Smith Maker, Syracuse, N.Y.?
According to David Williamson, the hammerless guns from L.C. Smith Maker started in August 1886 at serial number 16,000 and ended around 23,553 in 1888. David has been collating Syracuse SNs and might have a better idea as to DOM.
Please see http://www.picturetrail.com/sfx/album/view/22785410
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