At this current time i make my cartridges like this,
Made a stick that tapers as a mold to wrap around.
I take top cig papers and roll em around the tapered stick leaving about half inch past the narrow end and after licking the gummed edge i stick it to itself along the stick, then another lick on that half inch flap and fold it over and slightly up the stick, making a tapered flat bottom cartridge ready for loading.
I place these sleeves in a 9MM plastic tray to hold em uprite for loading.
Next I load 20 grains 3Fg Old E powder in each one.
Next i drop a .375 ball in each cartridge.
Now i lift one at a time out and twist the remaining paper tightly over the ball snugging them nice n tight against the powder.
I melt SPG lube in a shallow saucer, now I dip the cartridge ball end so the lube coats the entire ball and twisted paper.
After they harden overnight, i clip the twisted paper close to the ball leaving a lubed paper cartridge ready to load and shoot.
Before i lubed them i loaded and shot 50 some cartridges in a row with nothing lube wise except for ballistol on the arbor. I wiped the cylinder face after every 4 or 5 cylinder fulls, but otherwise no lube, no nitrated paper and no smoldering paper bits to ignite the the next cylinder full.
I did blow down the bore after each 6 rounds fired. These 50 some all went into a 5 inch circle at 30 yards off the bench.
Cleanup was almost as easy as using lube over the cylinder face. There was bits of paper in each cylinder after this test but nothing hindered the shooting except the occasional cap thing. Gotta do another test with lubed balls.
Already gave up on conicals as the ball seriously out classes them accuracy wise. Accuracy is my goal along with fast repeatability.
Gotta try the nitrated papers tho. Sounds great. Keep us posted as there are many interested in your quest.