In 1842 the production of all flintlock muskets for the U.S. government was halted. When the decision was made that same year to transform flintlock muskets to percussion using the cone-in-barrel technique, the Army had to determine how many flintlocks it had in inventory, and which weapons were suitable for transformation. Lieutenant Peter V. Hagner was appointed as the senior ordnance officer supervising the inspection and classification. Over the next six years Hanger found that 700,000 flintlock muskets were in inventory. As a first cut, all muskets manufactured prior to 1812 were condemned, as were all muskets manufactured after 1812 which were not deemed worth repairing and transforming. All "good and serviceable" muskets manufactured after 1831 were characterized as first-class arms and were not further inspected. Hagner's three inspectors -Elizur Bates from Springfield Armory and Philip Hoffman and later James P. Chapman from Harper's Ferry Armory - were given three gauges to inspect the muskets manufactured between 1812 and 1831. The first was a tapered plug gauge used to measure the musket's bore diameter at the muzzle. The second and third gauges were .690 and .705 inches, respectively. If a musket's bore gauged between .690 and .695 inches [17.5 and 17.65 mm] it was characterized as second-class. If it gauged between .695 inches and .704 inches, it was characterized as third-class. If it gauged more than .705 inches [17.9 mm] it was characterized as fourth-class and condemned. Condemned weapons were set aside at the arsenals for disposal, third-class weapons were not deemed suitable for transformation and were kept in storage essentially as war reserve materiel, while first and second-class weapons were considered suitable for transformation. Colonel Craig of the Ordnance Office wrote on 1 October 1854 that of the 707,011 flintlock muskets inspected 337,092 were assigned to the third and fourth classes. Regarding the quality of all the Army's smoothbore muskets, Craig stated that the inspection "shows at a glance the very large proportion of the arms that in point of quality fall below the proper standard, and when explained to the [Ordnance] Board that the inspection was made by two workmen from the armories who had been employed there at the time these arms were fabricated I can not [sic.] but think it will satisfy them that great carelessness must have existed at that time in the armories." In 1849 George Law, a New York City entrepreneur, purchased 144,353 of the condemned fourth-class smoothbore flintlock muskets from the Ordnance Office; 80 percent manufactured by national armories and 20 percent by private contractors. In subsequent years he rifled and percussioned many of these condemned arms and sold them, with many of them ending up in states that became part of the Confederacy, particularly as the Southern states built their arms inventories in the years preceeding the beginning of the Civil War. A rifled fourth-class weapon would have been notably inaccurate using standard .69 caliber expanding ball ammunition. I suspect that the marks on your musket indicte that it was one of the fourth-class weapons purchased by Law and transformed by him. Carefully measure the bore and you may have your answer.
Regards,
Don Dixon
[I don't know why the system has inserted the lines, and I cant remove it.]