link dont work, was it this gun? https://live.amoskeagauction.com/lot-det...%3D0%26page%3D1

18 bore cases exist but the gun maybe is a 20 or 16 ga

"Description:

serial #5116, 18 Bore, 7 1/2” barrels with mostly bright very fine bores, the right bore showing a bit more pinprick pitting and light oxidation, and otherwise crisp 9-groove rifling. The barrels of this handsome pistol retain perhaps 70% fading original plum-brown finish with contrasting gray showing some scattered light handling marks and sparse mild oxidation staining, most of the loss due to some areas of lighter gray patina overall. The barrels otherwise retain fine swirling damascus patterns throughout and the solid rib retains crisp “J. BRADDELL & SON. BELFAST” marking. The undersides show period London proof marks and a nominal bore marking of 23, though measurements place them closer to 18 bore (a little over 0.630” caliber). The action and lockplates retain perhaps 30% original case-hardened colors with scattered vibrant patches lurking about the protected areas, the left lockplate in particular with lovely vibrant colors throughout. The balance of the surfaces are toning to a pleasant medium gray-brown patina, both lockplates are maker-marked and the arm is embellished with attractive tasteful light foliate scrollwork and filigree. The checkered walnut stock and forend remain in very fine condition showing just some scattered light dings and handling marks, maintaining an attractive honest appearance with strong checkering throughout and excellent fit. The horn grip cap is intact and remains in near excellent condition. The pistol is sighted with a single medium German silver bead front sight and the barrel lock-up via Jones underlever is solid on-face. Equipped with extractors, double triggers and rebounding hammers which remain crisp. This attractive circa 1880s pistol remains a very fine example of the imposing and much sought-after howdah pistol. (13D11199-44) {ANTIQUE} (7000/9000)
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