It may well have been off face from many opening & closings with a dry hinge joint. I would think it would take some mighty powerful loads in a 20 gauge to put a Sterly off face.
That may be but the rotation arc is quite short and hinge joint pressure when opening and closing is low even when compressing ejector springs on a Sterlingworth that has them. Motor engine parts survive millions of high speed cycles with lubrication. Why would off face come from several thousand or less of turtle speed hinge joint movements without some thing else at play? As we say, food for thought.
