Howdy Deacon,

Not sure it this helps, but my experience with .38S&W is for an 1851 conversion with the original dimensioned .385 bore. That is a substantially larger than your bore. I have had some success with soft hollow base wad cutters, even with light charges of Amer. Select powder. I suspect that might get you started while you research your mold selection.

For what it's worth,

Rev. Chase

Morning y'all.
Coffee and tea are hot.

Learned good info. Took the Stop The Bleed class. Stopthebleed.org. There is a free on-line course.

I took the online course as part of my CCW course. Bought and carried quick-clot in addition to a trauma kit.
Good stuff when used properly.

Hit 72 and sunny here today, started out with drizzle, then by mid-morning turned real pretty. Worked today and then Sheepdog duty at the Spanish Ministry at Church. Y'all have a good one.

Rather than the typical 200 grain flat point CAS .44 Russian loads, I used Bear Creek's 246 grain, conical round nose .44 Russian/Special bullet over 5.3 grains of Unique.  That is listed in Lymann as a factory duplication load.  That should smack the plates with authority.

The GWII (Pietta) base pins are double groove as well (hard to tell from the parts drawing).  And I hate Pietta pins anyway, because the groove(s) are only on one side of the pin, not all the way around, so they have to be perfectly aligned when you insert it or it can get jammed.