Lyman 57W sight on the Model 70|Winchester Sights|Forum|Winchester Collector

Hi Y’all-

I have a couple quick questions about the factory installation of Lyman 57 series sights on the pre-war/transition M70s.  From their introduction in 1937 until 1946, the M70 standard rifle and carbine (but not the Super Grade) listed the Lyman 57W as an optional rear sight (with its own catalog symbols distinct from the Win 22G and Lyman 48WJS options).  

The pics below show a Lyman 57W (left) compared to a ’50s vintage Lyman 57WJS.  The obvious differences (not counting the later ‘stayset’ knobs) are the base block of the 57W, which is scalloped and extends below the stock line, and the presence of a clip-on slide cover.  

My questions are: 1) When did Lyman change the design from the 57W to the 57WJS?; and, 2) Did Winchester ever factory install the 57WJS on the M70?

The info I can find is fuzzy… According to Strobel’s sight book the 57 series was introduced in 1938, yet the Lyman 57W is clearly pictured on the M70 rifle/carbine with that sight option in the January 1, 1937 WRA catalog as well as in the component parts section.  The 57W option for the M70 was catalogued through 1946 and deleted in 1947, and the Lyman 57W (not 57WJS) was pictured in the component parts catalog at least as late as 1950.  According to Strobel, the redesign that changed the 57W into the 57WJS occurred sometime before 1950.  Rule’s M70 book, in discussing rear sights, clearly shows a photo of a 57WJS, not a 57W.

Hence my questions…  If the 57WJS didn’t come along until after the Lyman 57 sight option was dropped in 1947, then any M70 with a factory-installed 57 series sight should have the 57W, right?  Excluding the possibility of special order of course.  Or did the 57W -> 57WJS redesign occur earlier than Strobel implies, which means some M70s could carry factory installed 57WJS sights?  I know the redesign of the Lyman 48WJS from the full block that required stock inletting to the scalloped block that did not occurred 1946-47.  But what about the 57 series?

Any help appreciated… 

Lou

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