Within every Remington EtronX, primer is a group of subcomponents assembled to exceptionally tight tolerances. Primer cup dimensions are controlled to .0001″, and the priming mix is specially formulated for consistent ignition with a wide variety of powder types. Primers are tested for reliability from -20 degrees F to +150 degrees F. Remington EtronX unique tripod anvil design creates a larger strike area with maximum sensitivity, even with off-center firing pin strikes. Etronix primers are only for use with Remington model 700 Etronix rifles.