Bert H. said
The Model 55 made in 1957 – 1961 was a semi-auto single shot .22 rim fire rifle.  

Yep, that part I can confirm since it is up my alley.  The Model 55 rimfire used the Winchester 75 front sight.

I highly doubt the Model 55 center fire lever action used the 75 front sight since it was used primarily on Winchester .22’s.

After checking the pre-war Lyman catalog (#26), it states the #3 “WC” was specified for use on the 53 (.25/20, .32-20) and the 55 (.30-30).  The height of the Lyman #3 “WC” is .290″.  The #31 “T” was also specified by Lyman as correct on the same chart and is also .290″.

It is entirely possible the Lyman “31W” specified on the Winchester drawings is incorrect and should have said “#3” (it would not be the first, or even the 10th, time I have found an error on the drawings).

Best Regards,

Also, here are the Model 53 and Model 55 sight specs I referenced from the same catalog.