Daryl, I feel your pain. Most dealers don't have the equipment, knowhow, or maybe the sense to measure bore dimensions. What I don't understand is a dealer that deals in very expensive shotguns, and has a large inventory of them, and can't or won't measure dimensions. He's either stupid or crooked. The Brits have got all their proof laws set up the correct way. If you sell an out of proof gun there, you pay a hefty fine or lose your license. A good percentage of our dealers wouldn't be in business two months if that law was equally applied.