Reportedly, 100 each of the Model 1841 "Mississippi" rifles, Model 1842 muskets, and Model 1847 musketoons were converted using Merrill's breech loading system around 1861-1862. The alteration involved boring out the barrel and rifling it for use with .58 Minie balls, removing the original breech plug and installing the Merrill breech system as well as adding the lever catch to the barrel, adding a screw through the lock plate, and using a bolster with a cleanout screw. It has a brass blade front sight, three leaf rear sight, "V/P/eagle head" proofs on the left at the breech, the three-line Merrill marking on the lever, standard Harpers Ferry markings on the lock which is dated "1850", "JLR" and "H" marked on the left stock flat. Fitted with Colt pattern slip ring clamp with bayonet guide stud marked "567" (loose screw will not tighten snugly). Includes an extra nipple and patches inside the patch box.

Very good plus, polishing marks visible on the barrel, breech lever, and lock with some very light small patches of pitting on the breech lever, some light wear marks on the right side of the breech lever from rubbing against the hammer, and sharp inspection markings. Brass patch box and buttplate polished bright with the bands and trigger guard displaying an attractive lightly aged patina. Stock is very fine with some scattered scratches, scuffs dents, and a crisp inspector mark. Mechanically fine. A rare Civil War era Merrill conversion of a "Mississippi" rifle that would make a fine addition to any U.S. Martial collection.