Thread: New 6mm ARC from Hornady

That was one consideration @Wingman - but a huge consideration is also that the altered dimensions mean that a 6.5 Grendel round chambered in error won't allow the bolt to go into battery and fire. That would be exciting in all the wrong ways. When careless users are happily picking up magazines full of 300 Blackout and inserting then into a 223 and blowing it up, imagine how much simpler it would be to confuse 6.5 Grendel and 6mm ARC!