I mostly cast and shoot a Lee 200gn RF in 45LC. Here are my most accurate loads using the powders you mentioned. I also use a wad over the powder.
HP38/W231 7.6gn
Clays 5.5gn
Titegroup 7gn
You're the first in this thread to mention using a wad. I presume it is to take up space between the powder and bullet base to keep the powder at the primer end of the case?
Just curious, but what do you use for the wad?