Trail Boss, full case to the base of the bullet (about 19gr. weighed with a 405), NO compression will be a fine low pressure yet totally satisfying load for most shooting.
Of course, about 63ish gr. (or all you can get in) of FFg black powder will give you the real deal.
Ive used 19.0 to 21.0 if IMR 4227 with 300-405s and its worked well ('84 Mdl, .73SF)