Thus far I have NEVER experienced a split case, neck or base, regarding a .243 Winchester presentation. Since I always load full-boat, this is plain lucky or to be expected with LESS than ten reloads. Pushing fifteen reloads is something I never intend to attempt. My .243 Winchester powder of choice will always remain Hodgdon H4350 for general use. Some special applications will require Alliant RL-15 through RL-22, but that remains a specialty story or two. I only use Remington and Hornady brass, if that matters. Cliffy