That 3/4 ounce 20-gauge load was a pretty hot load with 2 3/4 drams of powder.
Opening Day 1911, 32-inch, 20-gauge, DHE-Grade load.jpg
The 20-gauge bulk smokeless powder loads from Remington Arms - Union Metallic Cartridge Co. in their 1911-12 catalog were 2 drams pushing 3/4 ounce of shot, 2 1/4 drams pushing 7/8 ounce of shot and those 2 1/2 dram loads pushing 7/8 ounce of shot in the longer shells.
1911-12 ARROW 20-gauge bulk smokeless powder.jpg
I suspect there is a misprint in this catalog, as in other years Load #22 is 2 1/4 drams of bulk smokeless powder --
Rem-UMC Arrow 20-gauge shells bulk 1915-16.jpg
It is probably a bit of a jump, but one might expect that the load being used in the 28-gauge was the 2 1/4 drams of Scotch Empire pushing 11/16 ounce of #7 chilled shown by Frank in another thread.
Threaded Mode