Edited by board administrator September 3, 2017, 9:12 am
It's certainly reasonable to assume the receiver forgings (AISI 1020) and parts (AISI 1040 and "tool steel" alloys) were sourced in Syracuse; by Hunter Arms and likely Ithaca and Baker in Batavia.
I don't know Winchester's source for their "Standard Ordnance Steel", but Winchester Nickle Steel came from Bethlehem and Midvale.
The big money for the steel makers was of course in railway, structural, and plate steels. Carnegie and Bethlehem were licensed to manufacture Krupp steel plate in 1897.
Lots more here