Vintage pigeon guns, as differentiated from those that sellers call pigeon guns to attract attention from potential buyers, are heavy guns (8 lbs. +, in England), to absorb the recoil of the 3 3/4-1 1/4 oz. loads used by serious shooters (even heavier loads were common in earlier days). They are long barreled, 30" being the minimum, and going to 34" at the extreme ......... with 30"-32" being very common. They are often single triggered, usually pistol gripped, often side-clipped, always tightly choked (if original), often proofed for 1 1/4 oz., often chambered for longer shells (3" +)and stocked high in the comb to help with the rise of the flyer out of the trap. Boxlocks and hammerless sidelocks are often built without a safety.
They're purpose built guns, with no effort spared to please the buyer, who may have certain eccentricities. They're not the same as a waterfowler, which may weigh in upwards of 10 lbs., but often found with many of the same attributes, other than being stocked high in the comb.
Oh, one more thing ............... they are mesmerizing to a few of us.
SRH
