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Flayderman's Guide to Antique American Firearms. "Following the US Civil War, the US government in 1867 decided to convert many of their percussion military arms to metallic cartridge breechloaders. The Sharps was one of those selected for conversion, and contracts were given to Sharps Rifle Manufacturing Company to alter rifles and carbines of their manufacturer. A total of 31,098 carbines and 1,086 rifles of all three styles were converted. In addition to the normal inspector markings found on Sharps percussion arms, an extra inspection stamp (initials DFC in a ribbon cartouche) was marked on the center of the left side of the buttstock. Conversions were refinished by the factory; when condition of the original stock required that it be replaced, a buttstock with no patchbox was used in all cases, regardless of the original model designation. Conversions bearing the "New Model 1865" will command a premium value. Rifles converted to 50-70 centerfire. All with three-groove lined barrels. Total 1,086 estimated made. Values Good $1,750, Fine $4,000"

Question: Where do you get the estimate that serial numbers 59,xxx would put it near the end of 1859 manufacture? The guide states "Percussion straight breech models were numbered consecutively from approximately 30,000 to approximately 150,000". There were approximately 33,000 New Model 1859 carbines and 5,100 new model 1859 rifles made", so the end of the NM 1859's would be about 68,000.