Speer and Lyman both have published .38 spl. Loads with 2400 showing STANDARD pressures with around 10 grains under 158s. MANY sources have shown heavier charges as safe (though most are cautious about approving some of the Keith level loadings). I do not prefer 2400 in .38 spl-it costs more due to the heavier charge weights and leaves partially burned powder in the bore which can wind up under the extractor star and temporarily tie up the gun. However, I have shot some 2400 in my .38s and it performs just fine.