1918 16g Field with Krupp over-stamped with Armor Steel

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As Bro. Tom said, Krupp barrels were cataloged by Hunter Arms as an available option only 1900-1905.
It seems likely that Krupp was licensed to Cockerill Sambre, as Fluss Stahl Krupp Essen marked tubes stamped with the "ACL" of Acier Cockerill Liegeoise or with “LLH” of Laurent Lochet-Habran are found on some U.S. maker's barrels.

The first Lefever with Krupp steel barrels was in 1894. c. 1904 B, C, D & E grades were offered with Krupp steel.

About 1906 the Baker R (replacing the A grade) was available with Krupp steel.

As mentioned, the 1910 Meriden Firearms Co. catalog shows the following grades and barrels:
A with Whitworth, Krupp, or 6-blade damascus for $250 with AE;
B with Krupp or 6-blade for $185 with AE;
C with Krupp or 4-blade for $110 with AE;
D "Trap Gun" with Krupp or 3-blade for $90 with AE;
E "Quail Gun" with Krupp and ONLY 16G for $60 (no AE offered);
F with Krupp or 3-blade for $60 with AE;
G with Krupp for $40.

The Meriden Tournament grade had Krupp in the Sears 1915 and 1917 catalogs

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and the Meriden Ejector No. 35

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Ithaca Flues No. 2 and higher offered Krupp in 1913.

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1917 and 1924 Janney, Semple, Hill & Co., Minneapolis catalogs Krupp starts with No. 3

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