My 1957-58 three-screw Single Six has a adjustable rear sight and just assumed that the Single Six always had adjustable sights. Wrong. A New Model Single-Six is available with a integral rear sight.

[Linked Image from i.imgur.com]

https://ruger.com/products/newModelSingleSixConvertible/specSheets/0629.html

[Linked Image from i.imgur.com]


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