Your post started me thinking about an old practice that I had forgotten about. Paper Patching. It's a rather archaic art, but Col Harrison of the NRA did some work years ago and found that he could drive cast bullets fully as fast as jacketed bullets with good accuracy.
I started digging around in my mental archives and doing some Googling and found this tutorial on paper patching.
LINKY!. After you've learned the basics of casting, you might want to explore paper patching.
Heck, I might explore paper patching in the springtime. I've got a couple of old .30-30s that I should dust off.