Tom;
I am not certain, but think you may be thinking of the Stevens 315 rather than the 311. The 315 models will normally have a 1915 patent date on them I beleieve & are striker fired rather than having internal hammers. These can be readily identified by the rear pin (sear) being higher in the frame than the front pin, (cocking lever). As I recall on the 5100/311 models the hammers & cocking lever are hinged on the same forward pin & the sears are hinged low in the frame behind behind them.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra