I designed my cases specifically to hold that much powder and the short wad column. There's no base wad, although the head of the cases are thicker than the case walls. I should note, I haven't noticed a need for a base wad and my fiddling with modern cases is showing that the typical modern base wad might take too much powder room for an appropriate black powder charge to fit in there with the wad column and ball.
I haven't needed to crimp or wax seal the roundball either. I size my case mouths a few thou small and let the spring of the case material do it's job.
Works great.
If I were to make a lot of ammunition up for a hunting trip I'd wax seal the mouths to keep moisture out.
Try that barrel warming trick today before the women take the kitchen over, let me know how it works for you. Make sure you give them a good oilrag rubdown afterwards, you'll notice they dry themselves very quickly as you get them out of the water, but the warm bath can take the normal thin film of oil off them and it's good to wipe them down with the oilrag while they're still warm.
--Tinker
