I load the 300 grain XTP with 20 grains* of H-110/Win 296 and use a CCI 350 primer**. H-110/Win 296 is a much cleaner burning powder than 2400. That makes for a stout load, but its accurate and deep penetrating. I use them sparingly in my two old S&Ws and even in my Ruger SBH, because of my old hand.
I'm not sure about reduced loads, I never use them. I like slow burning, case filling powder in the .44 Magnum.
*Hodgdon lists 19 grains of H-110/296 as max, so approach with caution.
**H-110/296 needs a magnum primer to insure good ignition.
PS: the 300 grain XTP, is one of the best .44 Magnum projectiles available in my opinion. For hunting and SD.
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