When the 28-gauge was added to the NID offerings in the first 1932 Ithaca catalog it was offered with 26- or 28-inch barrels. That remained the case through the 1939 Ithaca catalog. Beginning with the 1940 Ithaca catalog they only list 26-inch barrels for the 28-gauge. Long ago at one of The Vintage Cup events at Orvis Sandanona, Steve Barnett had a NID No. 7E 28-gauge on his tables. I snapped a few pics and while I never measured them, the tag lists 25-inch barrels?!?
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Ithaca never listed barrels longer than 30-inch for the 20-gauge NID, but I've seen several 32-inch 20-gauges.
When the 28-gauge was added to Ithaca doubles in the Flues era, the catalogs list 24- and 26-inch barrels up thru the July 1919 Ithaca catalog. From the December 1919 Ithaca catalog through the 1925 they only list 26-inch. For 22 years I've owned a Flues No. 1 Special 28-gauge with 30-inch Cockerill Steel barrels --
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Info from Walter showed it was shipped 05/25/1915 to F.K. Pierce.