Found this on another sight:
Winchester 450-LS Data
From: Speer #8, 1970:
.38 S&W - Winchester cases, Alcan
148-gr - Speer BB Wadcutter - 2.7 grs - 707 fps to 3.0 grs - 779 fps
(Red Dot 2.8 - 760 fps to 3.1 grs - 835 fps)
158-gr - Speer Lead Semi-wadcutter - 2.3 grs - 621 fps to 2.7 grs - 704 fps
(Red Dot 2.3 - 664 fps to 2.7 grs - 740 fps)
.38 Special - Speer/DWM cases, CCI 550
148-gr - Speer BB Wadcutter - 3.1 grs - 698 fps to 4.1 grs - 910 fps
(Red Dot 3.2 - 798 fps to 4.2 grs - 986 fps)
148-gr - Speer HB Wadcutter - 2.7 grs - 690 fps to 3.4 grs - 870 fps
(Red Dot 2.8 grs - 784 fps to 3.5 grs - 936 fps)
148-gr - Speer HB Wadcutter - 3.0 grs - 736 fps - lightest powder charge for reliable functioning and excellent accuracy in a standard Smith & Wesson Model 52 Target Auto. Pistol.
(Red Dot - 2.8 grs - 736 fps)
158-gr - Speer Lead SWC or RN - 4.0 grs - 822 fps to 4.5 grs - 938 fps
(Red Dot 4.2 grs - 934 fps to 4.7 grs - 1037 fps
.45 ACP - Federal cases, CCI 300
185-gr - Cast SWC - 4.7 grs - 751 fps to 5.1 grs - 803 fps
(Red Dot 4.2 grs - 776 fps to 4.7 grs - 854 fps)
200-gr - Speer SWC - 4.5 grs - 726 fps to 5.0 grs - 796 fps
(Red Dot 4.0 grs - 747 fps to 4.5 - 809 fps)
No other handgun loads were listed.
Red Dot loads included for comparison.
Apparently not a very versatile powder. There's no mention of it in Speer @#9.