The Western Cartridge Co. Super-X (progressive burning powder, high-velocity) 12-gauge 1 1/4 ounce and the 20-gauge 1 ounce loads were introduced in 1922, put up in their 2 3/4 inch FIELD shell --
Earliest Super-X Brochure, 12- & 20-gauges.jpg
Early Super-X 12-ga box, Super Excellant.jpg
Early Super-X 20-gauge box, Super Excellant.jpg
The 1 1/8 ounce 16-gauge Super-X load followed later that year or early 1923, but put up in their 2 9/16 inch FIELD shell.
The 12-gauge 3-inch Super-X load of 1 3/8 ounce of shot, put up in Western's 3-inch RECORD case finally hit the market in the 1924-5 time frame --
To Owners of Super Fox Guns notice slip.jpg
Early 12-gauge RECORD Super-X 3-inch.jpg
Super-X loads with the Lubaloy (copperized) shot first appear in the February 1, 1929,
Western Ammunition for Rifle, Revolver and Shotgun.
Early 12-gauge Super-X Lubaloy load side.jpg