Just an update. Barrel sped up a little with my load to 3070 fps. (83g retumbo 3.5" coal) shot my elk at 849 yards, double lung and the bullet was on the offhand side just under the hide, so all energy was dumped into the animal. Quite controlled expansion. Elk stayed on his feet for about 2 minutes, but never took a step. I was on him and ready, but could tell he was done.