Belly,.
I hunted and killed many elk with an 8mm Rem Mag shooting a 220 grain Hornady interlock. The interlock is not substantially different from the core lock. Keep your shots within reason for what ever accuracy you get from the core locks and hunt with confidence. I shoot elk with a 7mm 162 grain ELDX these days and am here to tell you the ELDX will do the same. You can not go wrong with either bullet.
8mmwapiti
