These "Fifth Model" Burnside carbines represent the completion of the evolution of General Ambrose Burnside's ingenious carbine design. The outbreak of the Civil War led to the purchase of over 50,000 Burnside carbines. They were the third most purchased breech loading carbine during the war, after only the Sharps and the Spencer. This example has the matching serial number on the frame and breech block, single letter inspection marks on various components, boxed script "EPR" and "RKW" inspection cartouches stamped on the left stock wrist, and "N.S.P." inspection initials ahead of the buttplate tang.