Cartridges were made by every army at the time that used flintlock muskets. They never could have fired 3 shots per minute with their muskets without them. Anyone could roll cartridges and the cartridges could be stored in barrels. So it really didn't matter how long it took because the soldier wasn't necessarily the one doing the rolling.
The 75 grains that he used for his 75 cal musket was too little. Makes a whoosh sound when it goes off. Need a 100 gr. charge or more of modern BP for the Bess. 100-gr to 110-gr. is typically used in reenactments. Although the fancy roller with the round top and recessed end is nice, don't need it. A simple piece of doweling works fine, and you sure don't need to use a marble to make the bottom pretty. All it needs to do is make a decent seal so the powder doesn't leak out the bottom. If you really want to get carried away, dip the bottom of the cartridges in wax. Seals them well, protects them from moisture, and lubes your cartridge block to make it easier to pull them in and out. I think I've done that 2-3 times over the last 6 years (overkill).
So that the black powder doesn't leak out while the cartridge is being store, instead of just folding the top over, you tuck it in to the slanted part of the paper for storage. When you put it into your cartridge box, then you pull the piece of paper out of the tucked in position so that it's ready for use.
The little home made funnel and 75 gr. measuring cup is a waste of time. Either use a powder scoop of the right volume or use a powder measure with integral funnel so you can just tip it in when you're ready to add the BP. Usually the rolling of the cartridge and the filling of the cartridge are not done at the same time. You roll a bunch of cartridges and then you fill and fold them all at once. Our reenactment group has "powder parties" where everyone brings a couple of hundred paper tubes that they've rolled to a central location for filling.
If you saw the movie "Master and Commander" where they were getting ready to fight another ship, you saw them pop open a barrel of pre-made paper cartridges and pass them out to the men. That was how it was done. They were pre-made and stored for use.
To use the cartridge they would tear off the end with their teeth, prime the pan, pour the powder down the barrel and stuff the paper with the ball down the barrel with the ramrod. For reenactments, of course, the ball is omitted...:grin:
Twisted_1in66