The Field Grade Flues was made with Smokeless Powder Steel barrels from beginning to end. 1912-13 Ithaca Gun Co. catalogue --
1925 Ithaca Gun Co. catalogue --
Actually the earlier Field Grade Lewis and Minier Model Ithacas also had Smokeless Powder Steel barrels, as did the Field Grade NID's from their late 1925 intoduction to at least 1935.