I have a 1940's model 12 16 gauge with 0.667 bore and 0.008 choke marked MOD. I believe the choke is factory unaltered. I agree that that seems light for a MOD choke but have had several others tell me it was normal from Winchester? I have never had enough confidence in it (based on some 16 yard trap shooting) to use it as my late season long range pheasant gun. I need to pattern it on paper. Just yesterday I passed on a model 12 16 gauge solid rib marked Imp.Mod. (really looking for same in full). I didn't have bore gauge to measure the constriction but close inspection showed that the choke had been probably opened up. I did score 3 boxes of Win Super X paper shells 2-16 gauge 2 9/16" roll crimped and 1 - 12 gauge 2 3/4" for all $40! Happy to get them.