I have a Cogswell & Harrison Avant Tout for sale on Consignment. when I was taking photos I noticed a 1-1/2 oz proof. The manufacturer told me it was built in1888. Does this indicate a rebarrel or were English guns proofed that heavy in those days? The gun weighs about 7 pounds and has high dimensions. Could it be a live pigeon gun or a water fowler? Link to photos: https://imgur.com/gallery/VBhpS0o