Missouri Bullets shows a 200 grain rnfp .45 acp sized to .452 with a brinnell hardness of 18. They show a .45 Colt 200 grain rnfp sized to .452 with a brinnell hardness of 12. Both show a crimp groove. These bullets appear identical except for the hardness. I assume that both will fire just fine and dandy in both my Ruger Blackhawk and my son's Ruger 1911. If so, why do they call one an ACP and the other a COLT?