Gunner, I use a 405 gr flat tip for an '86 and a 500 gr for a '74, both lyman moulds, I only use black powder in the sharps, but the 86 is such a pain to clean, I normally use smokless in it. I've tried IMR 3031, IMR 4064 and XMP 5744. The load I use for the kids and grandkids to shoot is 35 grains of IMR 3031, it shoots well with relatively low recoil. It should work well with your 380 grain bullet equally well. I'm willing to wager that you'd find this load to your liking.
ps, the dacron wad will help maintain the powder in a consistant position, and this should help with accuracy, but is not an absolute necessity.
From Lyman Castbullet Handbook:
#457124
IMR 4198 starting: 23 grain w/ dacron wad = 1039 fps from a 24' barrel
Max for Trapdoor: 30 grain w/ dacron wad = 1363 fps
Max for Ruger #1: 50 grain = 2220 fps