Recoiljunky,
If I remember right it was 1973 when the transfer bar was added.I' m 99% sure it was 1973.I don' t remember what year it was they added the warning on the barrel.I believe it was close to that time.If I' m not mistaken it was by a court order partly in a agreement dealing with a lawsuit that was brought against Ruger Some Yahoo shot himself and tried or did sue Ruger.Bill Ruger was very big on safety but I' m sure it wasn' t his idea to add the warning.
Ruger Redhawk