It doesn't show a 150 gr lswc but does show a 148gr Wad Cutter with trailboss.
2.0 gr 625 fps to 2.3 gr 675 fps 15700 PSI OAL 1.160
Oh and guys Lee is the only book I have that actually lists Trailboss powder. I've not seen it in my Lyman, Speer or Hornady books at all. Oh and all my books are the latest editions.
A rule of thumb is 70% of case capacity with no compression. That is listed in a PDF file by IMR as well as some load data listed there in a couple of PDF files.
Here is the data listed in the PDF for handgun loads:
38 SPECIAL
Case: Winchester Twist: 1:18.75" Barrel: 7.7" Trim: 1.145" Primer: Winchester SP
Bullet: 125 GR. LRNFP Dia. .358" COL: 1.445"
Trail Boss 3.0 753 11,600 CUP 5.3 952 13,400 CUP
Bullet: 158 GR. LSWC Dia. .357" COL: 1.455"
Trail Boss 2.7 661 11,400 PSI 4.2 804 13,700 CUP