Capt. Charles Askins and E.M. Sweeley published a series “Ballistics of the Shotgun”, and in April, 1922
Outdoor Life, “Late Developments in Guns and Ammunition” made reference to a "Special Fox gun"
https://archive.org/details/sim_outd...e/234/mode/2up
DuPont Oval was the only powder used in the early Super-X line.