I recently came a cross the case in the picture below. 3.7 inch AA gun cases turn up on a regular basis, most of which date to the 1939 - 42 era. This one, however, is dated 1949. I would have thought that there was a large surplus of these cases following the end of the war in 1945 and wondered if anyone knew why there would be a need for new production for a gun in decline.

