ussokc, (Which Okie City? The cruiser or the sub??)
And, how far down the coast are you?
Your 656,5xx probably shipped early 1936. I have a listing in the DB for 654,9xx as shipping in 12/35 and 657,9xx shipping in 10/36.
What's the sight bead on your later one??

David,
Interesting! (We had a big discussion a couple of years ago as to whether the mounting screw should be counted or not seeing as how they all had it. The consensus was to just count the adjusting screws. Hence "1 screw" early sights and "2 screw" later ones.)
Your "2 screw" sight is right on the cusp of the change over.
The latest 1 screw gun I have a date for shipped 06/32 and the earliest 2 screw gun is now yours shipped 04/34.
645,515 is a 1 screw but I don't have a shipping date. I have a listing for 645,5xx as shipping in 12/33, but don't know if it was a 1 or 2 screw. (AAARGH!!)

__________________
Dean
SWCA #680 SWHF #446