The Sound, Feel, and Smell - stepping back in time - yep, I guess thats what it's all about...and making your own Cartridges and other equipment makes the experience more satisfying, IMHO.
I'm sure others may chime in, but a few Pointers. You can start out with Newspaper, which is normally .003", but it can be fragile. A lot of people use the Artist Pad Newsprint (.005"), which is usually available at most Art Supply/Craft Stores (take your Micrometer; some of it is pretty cheap & thin). Grocery paper bag can work, but it's awfully thick, and not for the Dentitionally Challenged. The Paper Bags the Liquor Store uses are thinner (.004"), and pretty tough, and work well also. For Lube I dip mine in a mix of Beeswax & Olive or Castor Oil, but there are many receipes. You'll need to settle on a Ball Size; Paper Cartridges require a looser Ball than a Rifle. I currently shoot a .662 out of my .69 Charleville. Some go bigger, some go smaller, and I'm always experimenting. You'll need a Cartridge Box with a Wooden Block for the Cartridges, or at least a Block for your Range Box. Remember most of the Original Load Data you see includes the priming charge. If you're going to prime from a priming horn/flask adjust your loads accordingly.
You have quite an experience ahead of you, and while I doubt you will abandon your Rifle, it will no doubt become a little jealous of the relationship you develop with your new Musket...
E