Lee 300 ULTRA MAG and 300 H&H Factory Crimp Die crimps the bullet in place more firmly than any other tool. Tests demonstrate that even bullets which have no crimp groove will shoot more accurately. A firm crimp improves accuracy because 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.
WARNING: This product may contain steel alloyed with trace amounts of lead and other elements which are known to the State of California to cause reproductive harm and cancer. For more information, go to www.P65Warnings.ca.gov. To prevent exposure, do not alter the product by welding, grinding, etc.