Your A Grade, as Drew said, is an early gun. The hand cut Patent dates tell the story of the design. Im away from my records, but think those might all be Frank Hollenbeck patents. No factory records are known to exist, but Id guess late 1892 or 1893 as its birthday. Note that most of the engraving is actuall etching, with maybe a bit of hand engraving here and there. The bird motif on your gun seems like a later design for engraving as earlier ones tended to be more elaborate and then got simpler as the years went on. Barrel length is unusual , but as in most early guns of many makers, one never says never.
