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Diamond Arms Company and Nitro King are both trade name used by the Shapleigh Hardware Company of St. Louis, Missouri. Some of the guns were imported from various Belgian sources, but they were also made by W.H.Davenport Firearms Co (1890's - ), Iver Johnson Arms & Cycle Works (early 1900's - ), J. Stevens Arms (before 1942), and Savage Arms. If there is an oval with ELG* stamped on the barrel or action, it is from Belgium, but being a 410 makes that unlikely. That also eliminates Davenport as the maker.
Both 'King Nitro' and 'Central Arms Co' are trademarks of the Shapleigh Hardware Co, which was a major catalog retailer from the late 1800's well into the 20th century. The shotguns marketed under that name were made for Shapleigh by different companies, notably Davenport Firearms, Crescent, Hopkins & Allen, and Stevens. We'd have to see the shotgun to determine which manufacturer actually made the shotgun. www.countrygunsmith.net
I believe that King Nitro was a model name of Shapleigh Arms Co, St. Louis, MO.
Some models of Diamond Arms were made by the Crescent Fire Arms Company for the Shapleigh Hardware Company of St, Louis, Mo. between 1982 and about 1922.
Diamond Arms shotguns were made by several manufacturers, but if the rest of the patent date is '13', this one was by J. Stevens Arms and retailed by Shapleigh Hardware.
i would like to know this myself i hacve one
The 12 gauge King Nitro number 3411 is likely a vintage shotgun manufactured by King Nitro. It may have a 2 3/4" chamber and be of good quality, but specific details about its features and history would require further research or inspection by a gun expert.
Diamond Arms Company: Trade name used by the Shapleigh Hardware Company of St. Louis, Missouri on shotguns they retailed. Probably manufactured by J. Stevens Arms, but possibly a Belgian import. Look for an oval around "ELG*". If it has it, it is Belgian, but most of these imports stopped coming over when WWI started.
King Nitro was a trade name used by Shapleigh Hardware of St Louise on guns made by Crescent Firearms and J. Stevens Arms.
Utility gun, probably made in Belgium between 1890 and 1914, or by Crescent, Davenport, or Stevens between 1915 and 1940, and sold through Shapleigh Hardware.
MISSISSIPPI VALLEY ARMS CO was a tradename used by Shapleigh Hardware of St. Louis on shotguns made by Crescent Fire Arms Company, 1893-1930. A .410 would be unlikely to have been made by Crescent before WWI. 1903
Adco has no connection to your shotgun. They import semi-automatic shotguns made in Turkey. Diamond Arms Co was a trade name used by Shapleigh Hardware of St Louis, MO, on shotguns imported from Belgium c. 1880-WWI or made by Stevens and Iver Johnson from about 1900-1940. A single shot with serial numbers is most likely an Iver Johnson Champion.