Encouraged by an ongoing military contract, Colt turned his eye toward the civilian market in 1848. Civilian pocket revolvers, such as the Wells Fargo or 1849 Pocket, were .31 calibre pistols that fit easily in a coat pocket. Just as silver spring steel allowed Colt to adapt a .44 cylinder to a .36 frame, it permitted the .31 cal. 1849 Pocket revolver to be upgraded to a .36 cal.