Good start,
As to use, they were used from 1927 forward
and then maybe a repair and reproofed
or someone just got a wild hare and wanted an updated proof
for more modern ammo.
Chambers are still 65 mm or 2 1/2 inch
http://www.rstshells.com/rst_classic_shotshells_shotshells.htm
Mike

Last edited by skeettx; 11/20/13 03:58 PM.