Lee .40 S&W / 10mm Auto Carbide Factory Crimp Die
This die sizes the cartridge while being crimped so every round will positively chamber freely with factory like dependability. The adjusting screw quickly and easily sets the desired amount of crimp. Trim Length is not critical so this extra operation takes less time than it would if cases were trimmed and chamfered. A firm crimp is essential for dependable and accurate ammunition, as it eliminates the problems of poor ignition of slow burning magnums and pressure must build to a higher level before the bullet begins to move. This higher start pressure insures a more uniform pressure curve and less velocity variation. Includes a plastic storage container.