Garrett, I forgot to mention that your chamber length might still be 2 9/16". My 1939 is still 2 9/16". In the "Legend Lives", John states that the chambers on some were changed as early as the late 20's, but I do know that by the late 30's early 1940's it was 2 3/4". There are shell manufacturers that sell 2 1/2" shells, and if you reload there are more recipes than you will ever shoot. If you join the 16 Ga. Reloaders and the 16 ga. Society http://www.16ga.com/home/home.html it is a one-time monetary fee. While you are at it, if not a member here, please join.