Between 1843 and 1855 a total of 275,000 of this Model were manufactured by Springfield and Harpers Ferry Armories ,of which 172,000 were turned out at Springfield alone. The bayonet utilized for this model musket was the Model 1842 socket bayonet, which was 20-1/2 inches long, with a 2-7/8 inch socket and an 18-inch triangular blade. The U.S. Model 1842 Musket was the first arm to be produced at both the Harpers Ferry and Springfield Armories on a completely interchangeable basis, and aside even from this significant fact, holds a prominent position in the development of U.S. military shoulder arms. This was the first regulation percussion arm produced in the national armories , and at the same time, the last of the .69 caliber smoothbores.
The 1843 lock plate date makes this a very early example of the U.S. Model Musket.
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Part of a description from ‘Ancestryguns’ for one of these M1842s they were selling.
”The Model 1842 was the first regulation percussion musket to be manufactured at both Springfield and Harpers Ferry Armories, as well as the first to be produced by both national armories with fully-interchangeable parts. These were also the last .69 caliber smoothbore arms to be produced by the U.S. government. Approximately 275,000 were manufactured between 1844 and 1855, with only one-third of these produced at Harpers Ferry. Along with usage during the Mexican-American War in 1846 through 1848, these would have been in the hands of local militia all over the antebellum United States and used by both combatants at the outbreak of the American Civil War.
Both the original smoothbore version and the modified rifled version of the Model 1842 were used in the American Civil War. The smoothbore version was produced without sights (except for a cast one on the barrel band). When Model 1842 muskets were modified to have rifled barrels, sights were usually added at the same time as the rifling.”
