This R&D conversion is for the 1860 Uberti. The RD1860U converts your Uberti 1860 Army style revolver to fire the venerable .45 Colt or .45 Schofield Cowboy cartridges! The cylinder was engineered to have a five shot capacity, and to be able to use it in CAS competition, it was designed with 10 stop notches. The extra stop notches are the safety notches and lock the chambers out of the firing chain. The RD1860U was examined and approved for SASS use by the Territorial Governors. The RD1860U is to be used with either smokeless Cowboy loads or Black Powder 45 Colt/Schofield ammunition. Please see our large selection of cowboy ammunition. NOTE: We recently discovered these converters DO NOT WORK with the older Western Arms Uberti 1860s. (If, after installation, you are unsure of the fit, please take your revolver to a competent gunsmith or contact R & D Gun Shop to make sure you have the cylinder installed correctly.)