Hello, Roy, and thanks for your informative reply adding to my knowledge about this old rifle. The one constant that I have learned in my association with these rifles is that there is always something new and unexpected. I had gone so far as to surmise that the"No.1 S.R." meant exactly what you have said, but I did not know for sure and did not know the context. I guess that this old girl is a keeper. I'm still looking for one like your recently acquired Watson Bros. -- congratulations. Keep well.