I tried to:rolleyes:. I meant the change in cylinders from old style to new style isn't related to the change from old model to new model guns in 1973. The change in the cylinders transition from old style to new style began about 3 years later and took a year or two to be completed. During that transition period guns were shipped with old style LR cylinder and new style Mag cylinder, or new style LR cyl and old style Mag cyl, or both cylinders new style.