I'm fairly convinced that this one is a A-Grade gun now (from a Dr. Drew post over on Shotgun World back in 2017) because of it's "Twist" barrels.

"According to the best serial number chronology, the one in the second edition of Walter Snyder's book, the gun in question is from 1900. The AA was number three in the hammer gun grades. Quality X had Cockerill Steel barrels, Quality A had Twist barrels and the Quality AA had Damascus barrels, all on essentially the same receiver. From Walter's book "The new Quality AA was introduced during 1898. Like its kin, the Quality 1 1/2 hammerless gun that was also introduced that year, the distinguishing feature of the model was its Damascus Steel barrels." The Quality F, the highest grade hammer gun was dropped from the offerings between 1892 and 1894. In 1900, Ithaca Gun Co. built 2990 hammer guns and 4459 hammerless guns."

Dr. Drew is the gift that keeps on giving (both here and elsewhere it seems). Thank you again Dr. Drew.