16 Gauge Vulcan, 1 Frame 28 inch barrels choked m,f

[Researcher]

“But look at the target loads that all the major ammunition manufacturers produce. Winchester, Federal, Remington--they use their very best components and materials for their target loads. You’ll rarely see a 12-gauge load with more than 1 1/8 ounces of shot, and most of them are no heavier than a 3 ¼ dram equivalent of powder.

That has more to do with the ATA limiting trap loads to 1 1/8 ounce beginning April 1940. Before that there were plenty of 1 1/4 ounce trap loads. These were serious trap loads in the 1930s --

Super-Trap Load Lubaloy.jpg

Wester RECORD Super Trap Lubaloy 01.JPG

Western RECORD Super Trap Lubaloy 02.JPG

Western RECORD Super Trap.JPG

The heaviest trap/Pigeon load Western Cartridge Co. offered from 1929 to 1949 was a 12-gauge, 3-inch, Super-X, Lubaloy, handicap trap and Pigeon load with a maximum charge of progressive burning powder pushing 1 1/4 ounce of copper plated #7 or #7 1/2 shot. See the *

July 1, 1929, bottom of page 17.jpeg

[edgarspencer]

I'd love to hear what your Metallurgist friend has to say about how badly this 'fluid steel' has aged. I only have a masters in Applied Metallurgy, so all I know is it's only "Fluid", going from furnace to mold. After that, it's just steel.
Given your gun is a one frame 28", you're not going duck hunting, and any pheasant and upland load appropriate is going to be easily digested.
Copper plated shot shot reacts much the same as the un-plated lead, and has no deleterious effect on the barrels. The whole point of keeping loads reasonable, getting that lead moving no faster than it needs to be going, is to reduce recoil on the 100 year old wood. Anything you think you need 1 1/8 ozs for, will be equally well accomplished with 7/8 to 1oz. 1175-1200 fps loads are unlikely to damage your 'aged, fluid steel' barrels.