Another great powder for +P .38 loads (and for .357 Magnum as well) is SR 4756. I believe it's discontinued, but there is still some out there. I load 6 grains with a SP magnum primer and use the 140 grain Hornady XTP. I prefer the old Speer 146 grain but it's long gone.
Last edited by Mannlicher; 10/18/22.
