I have recently finished my first AR 15 build. I must say that this thing is a shooter for sure. Now that I have a very capable .223 predator rig I am looking into an upper for hunting mule deer. I lot of people have suggested the 6.5 Grendle, the 450 bushmaster and the 500 beowulf. I have no doubt that any of these rounds is capable of downing a mule deer with a well place round. The 6.5 grendle round has piqued my interest. What I am looking for is real world effective ranges that a grendle round can destroy the vitals and put a deer on the ground. In my search it seems that all I have found is hype and tall tails. Hopefully someone can steer me toward a credible source.