These seating stems are designed to fit Hornady® Custom Grade™ Dies and are machined to fit the profile of the A-MAX, A-Tip®, ELD Match, ELD-X, FTX and MonoFlex bullets to seat them as precisely as possible without damaging bullets. (Not compatible with other manufacturers’ dies.) Bullet: FTX™ Size: 50 Cal .500" 300 gr. (500 S&W Mag)