Rastus... yes, many if not all of the VV pistol powders are triple based with nitroguanidine (sp) used as a retardant, but still offering energy to the reaction, producing higher velocity at lower peak pressure... IIRC most of the case separations I personally saw were loaded with heavy cast bullets and 540 powder...I never switched to a 38super, but friends that had both, tried to use similar loads in major 9 for the old 175 power factor... I did manage to blow up a case in a P35 and standard length 17 with some borrowed ammo.... luckily no damage to me or the pistols... in the 80s it was not uncommon to see someone at a match with "38 super face" with particles of powder imbedded in their face