Can anyone confirm at what point S&W went to the two pin extractor on the K-frame, as opposed to the one pin? Was it when they changed to the short action, or at some other point? I know the extractor rod thread changed from right- to left- hand in 61, but I can't pin down the extractor itself.
The two dowels were a feature of the Model 1905 2nd change. This variation dates from 1906-1909. So, yeah, just a bit before the Post-War transitional guns.