.58 caliber. 40" barrel secured by three flat spring retained barrel bands. NSN. Bright finish, iron furniture, brass nose cap, walnut stock. Standard two-line U.S./SPRINGFIELD lock marking with {Spread-Winged Eagle} on tape primer door, dated 1858 at rear of lock. Barrel with no visible date and the standard V/P/{Eagle Head} proof marks that are somewhat weak. No cartouches present on counterpane. Correct 1858 pattern rear sight with curved top sight blades, correct musket style combination front sight and socket bayonet lug. Maynard tape primer mechanism remains complete. Retains both sling swivels and an original swelled-shank, tulip-head ramrod. A "transitional" 1858 dated example, the gun utilizes a left over brass nose cap from the earlier production Type I 1855 Rifle Muskets, but uses the new 1858 pattern rear sight from the Type II Rifle Muskets. A solid example of the standard US military long arm in service immediately prior to the outbreak of the American Civil War.