Shotgun Springfield J Stevens

I've got 2 double barrels from my great grandfather. The first says on the left side Springfield, under that is J Steven's arms company, and under that is chicopee falls mass usa. On the right side from what I've read is 5000 for the action. It's a 16ga and has checkered stock and forearm as well as capped half pistol grip. The other is a Montgomery Wards 20ga with the same 5000 on the right and features as the other. The forearm is wider and appears more rectangular than the 16's streamlined appearance.The 16 appears to of been case hardened and the 20 ga looks blued.

I still am not sure if they are 315's or 311's. I need a trigger guard for the 16 as the rear trigger will not fire unless you really apply pressure to it. I would like to be able to get a 100% clear answer so I may include it on a piece of paper with the shotguns when I pass them down eventually to my child expected in March.