In 1937, Savage Arms Corp. introduced three new hammerless break-action guns -- Model 220 single barrel, Model 420 over/under (and the nicer stocked Model 430) and a side-by-side with a trigger-plate action the Model 320 --

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Savage Arms Corp. must have decided competing with their A.H. Fox line wasn't a good idea and teh Model 320 was gone by the 1939 catalog. So, to get a lower priced double they added the Fox Model B to their offerings with an insert included in some of their 1939 A.H. Fox catalogs.

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Savage took the internal parts of their J. Stevens Arms Co. No. 530 and put them in a slightly nicer profiled, black gun metal finished frame with a bit nicer stock and called it the Fox Model B. The Model B was included in their 1940 A.H. Fox catalog --

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