I disassembled one of those old DC Co 577 rounds to examine how they were loaded. I will see if I can find the pics/details.
Edit: I went and took a couple of pics. Left is Kynoch - Right is DC Co. I cannot say for certain if the DC Co cartridge had a wisp of cotton in it although I do not think so.
Quite the difference in the amount of powder between the two rounds and not the different type shape of the grains
I had also disassembled a 56-50 Spencer round at some point.
