I use HS-6 in 38/357 & 9mm loads and find that it is in the area of Unique powder for it's use for tartget and full loads.

In my 686 6" I got the following loads with HS-6 powder;
38 spl 158 Lwc at 989fps
357 magnum "..... 1108fps

With a C9 3.5" pistol;
115 fmj... 1020 to 1182fps
147 tcm ... 805 to 975fps.

Groups on paper can be good or bad, with this powder, in my 9mm's.
Good loading.