Frank Wesson rifles were a series of single-shot rifles manufactured between 1859 and 1888 in Worcester, Massachusetts. They were purchased by many state governments during the American Civil War, including Illinois, Indiana, Kansas, Kentucky, Missouri, and Ohio. They were one of the first rifles to use rimfire metallic cartridges. The rifles were initially made in .22, .32, .38, and .44 rimfire. Centerfire cartridges were added later, and some rifles were capable of firing rimfire or centerfire cartridges, by altering an adjustment on the hammer.