unique isnt a slow burning powder like bluedot or 2400, yes it deffinately slower then green dot and alot slower then bullseye, but its still considered a fast burning powder though its actually a moderate burning powder, and its used alot in reduced cowboy action loads but are shot in SA revolvers so being a little under pressured isnt a big deal but in a auto pistol being slightly under pressure could mean it may not cycle the action, i was mainly wondering if anyone had experience with seeing how far you could reduce unique charges that still function in an auto.