I'm interested in the history of firearms, especially black powder ones. Sadly I'm not good at looking for sources.
What I wanted to find out is the details of paper cartridges for Colt and Remington revolvers. Remington 1858 is said to have used "from 25 to 30 grains and a conical ball". The thing is, what I can tell from using relatively exact replica, chamber can hold around 40 grains and conical, and 45 grains with round ball. At the same time, it was well known (as far as I could find out, sorry for the lack of source) that you don't want gunpowder just next to the lead, because heat will make lead deposit in the muzzle faster, lowering amount of shoots between cleanings. Also, the closer ball is to the rim of the cylinder, the smoothest transition to the muzzle, good for accuracy and gun longevity. Thus, it's hard for me to believe people back then didn't use anything.
All modern paper cartridge making manuals tells us to use cornstarch, cornmeal, semolina, sometimes felt circles.
But what was really used?