Hi, I have a Stevens 5100 side-by-side shotgun, but I've been unable to determine when it was made. Can anyone out there help out? Here's what I know. On one side it says Springfield J. Stevens Arms Co., Chicopee Fall Mass, USA. On the other side, it just says 5100. On the bottom, there is a small circle behind the hinge that looks like it has an 11 inside it. The person who stamped it did not have the tool square, and the bottom of the circle and numbers or letters did not stamp. I was told when I bought it that they thought it was made in the 50s, but I've also heard that the J in J. Stevens was dropped in the 40s. On top of the barrels, it says Selected Forged Steel, and Proof Tested 16 Gauge 2-3/4 Chamber. All of the metal is excellent, and the walnut shows typical wear but is nice. Nice cut checkering too. Someone back when put one of those red rubber recoil pads on it that say Red Head co, Chicago. Nice looking, but it would be nice to have the original plate. Oh well. Anyway, I'm dying to know when this gun was made. Does anyone know?