You guys are making this too hard; this ain't rocket science if you use some common sense and open a reloading manual.
Here are two loads that have been very accurate in any .38 Special revolver I've owned.
The first is a 148 grain hollow base wadcutter and 2.8 grains of Bulleseye, seated flush with the case mouth and jsut enough crimp to remove any flare.
The second is a 158 grain lead semiwadcutter (cast or swaged, doesn't matter) and 3.6 grains of Bullseye, with a moderate crimp.
Try those.
+1
I also use these same loads in .357 brass, works great.
It easy to accumulate way too many powders, thinking that every firearm needs its own special load. I've found that Bullseye meets 99% of my needs (target shooting), and 2400 for the other 1% (full power .357). I have some Unique, but don't really have any use for it that can't be done better with Bullseye or 2400.