The .410-bore shell first appears in the U.S. circa 1915, kind of jointly evolving from the European 12mm and the American .44-40 Shot/.44XL Shot cartridges. The 2-inch .410-bore shells carried a load of 3/10 ounce of shot and the 2 1/2 inch shell a load of 3/8 ounce of shot. There are no .410-bore shells in the Remington Arms - Union Metallic Cartridge Co. 1913-14 catalogue, but they are in the 1915-16 --
1923 --
From the J. Stevens Arms & Tool Co. General Catalog No. 54 --
For some reason when non-corrosive priming was first being introduced to American shotshells, the .410-bore shells got it first, circa 1930, with the larger shells getting it within the next year or two.
The 3-inch .410-bore shell with 3/4 ounce of shot was introduced in mid-1933 with the Winchester Model 42. I've posted this before, but will paste it in here again --
Ithaca Gun Co. 3-inch .410-bore Chambering -- July 1933
National Sportsman –
"We have not seen the official announcement but we have heard rumors that a 3" .410 shell was coming and on April 13th Norman Pillot of Houston, Texas, whom you may remember as having won the Amateur Live Bird Championship at Kansas City a short time ago, if my memory serves me right, wrote us that he was sending the barrels of his No. 4 ejector .410 Ithaca to be chambered for the new 3" shells. He also wrote us that last year he killed 180 ducks, 120 doves, 40 jacksnipe and broke 47x50 Skeet targets with this same .410 Ithaca.
In anticipating the stepping up of the .410 load, as we have previously anticipated the stepping up of loads for other gauges, all our .410's from the least expensive to the most expensive in either Ithaca, Lefever, or Westerns, have been built with material and strength enough to be rechambered for the 3" .410 and then handle it with a great big factor of safety.
I think it would be well to caution all users of .410s against using a 3" shell in the shorter chamber and I think that caution would bear repeating from time to time as applied to all makes of guns, because they still keep doing it with disastrous results.
You may say that any of our three outfits will furnish any of their .410s chambered for the 3" shell without additional charge for the longer chambering, and you may also say that the Ithaca Gun Company will rechamber an Ithaca or a gun of any other make for the 3" shell at a cost of $2.50 per barrel; and all the Ithaca Gun Company would need would be the barrels."