The old Richland Plainsman rifle was a .38 that used the .375 roundball that is used in BP revolvers. The gun in that caliber was not popular for some reason. I can see the versatility of having the same ball for rifle and pistol. Only wish I could use that caliber here in CT for hunting. Alas I am limited to a .32 or .36 using patched round ball for small game on state land and .45 and larger for deer on state land. On private land, anything goes, but trying to get hunting permission is a lesson in frustration.