I'm in CT, New Haven area, I checked the year it's 1937. Here's what it say in the FAQ section about the chamber size. "Hunter Arms Company lengthened the 20 gauge chambers from 2 1/2" to 2 3/4" in 1936. L.C. Smith and Fulton 16 gauge guns manufactured as late as 1939 are still found to have 2 9/16" chambers.""
If mine was made in 1937 why does the manufacture's card says 2 1/4?