I never had a problem with RP , because it is thinner everything goes smoothly , haven't any split cases or loose primers . I'm shooting 230gr FMJ's .451 my brass sizes down to .468 with RP brass is .010 think and Federal is .011 Giving .003 neck tension on RP and .005 on Federal , both have enough grip . I didn't know that Remington brass isn't designed to be reloaded , I will check into that . Thank You .