From the 1890s into the early 1920s, these longer shot shells didn't carry a heavier payload than one could get in a 2 3/4 inch 12-gauge shell, just more/better wadding, which many serious Pigeon shooters believed to be an advantage.
I should have included -- from our North American ammunition manufacturers -- in that statement. What some of the old time shooters stuffed in them who knows?
The Super-X 3 inch 12 gauge shell with 1 3/8 oz of shot and the 2 3/4 inch 3 3/4 dram equivalent 1 1/4 oz load (1330 fps) were both introduced in 1922. Winchester/Western brought out the 12 gauge 3 inch magnum with 1 5/8 oz of shot in 1935, the same year as the introduction of the Model 12 Heavy Duck gun.
The 2 3/4 inch 1 1/4 ounce 12-gauge and one ounce 20-gauge Super-X loads were introduced in 1922. The 2 9/16 inch 1 1/8 ounce 16-gauge Super-X load was introduced shortly thereafter. The 3-inch Super-X load with 1 3/8 ounce of shot don't show up on the Western Cartridge Co. price lists until
1923. A.H. Fox Gun Co. included this slip in their catalogs and Super-Fox brochures when the progressive burning powder 12-gauge 3-inch Super-X loads finally came out --
Edited to change date shown in red, previously misstated as 1925.
