There were shotguns stamped Keystone and Keystone Arms Co. made by W. H. Davenport Arms Co. They were distributed/retailed by E. K. Tryon Jr. & Co. of Phildelphia, Pa. My list shows a New Keystone Rapid Fire Steel as a Crescent single shot.
coigne
No. Remington shotguns are made in the USA.
Barton & co shotguns were made in Liege, Belgium.
When was J J Weston Shotguns made
Winchester made these pump action shotguns in there New Haven Conn.plant from 1964-1981.
indiana
originally = Ithaca, New York second = king ferry, New York now = sandusky, Ohio
Parker brothers shotguns were made from 1866-1934,Remington took them over in 1934 and the plant was moved to Ilion,New York in 1938.There were 4,500 transition guns made from 1934-1937,and there were 1,600 parker shotguns made at the Ilion plant before production stopped in 1942.I hope this answers your question.
Made in Turkey.
Tryon was an early gun manufacturer in the Philadelphia area, going back to 1812 or so. Around 1890, they began selling guns made by others under their Keystone brand name, a common practice. Most of their shotguns were made by Savage. Unfortunately, there is no real serial number public database for those store brand guns.
CBC for one Stoeger Condor and Uplander shotguns, also at least some Rossi shotguns