RE: 100 vs. 150
I elk hunt and usually run 100gr. or less of Black Mag'3 and 300gr. bullets. This load shoots completely through an elk unless big bone is hit. I also limit my shots to 120 yards or less. Have shot some at 80 yards. I usually get drawn for antlerless as the chances are better and I am basically a meat hunter. Big cows are as hard to put down as big bulls. They are not quite as thick but they have a lot of staying power after a deadly hit if they see you and know you are after them. I have not seen a reason to load 150 grains although if I intended to shoot over 150 yards I would spend a lot of time trying it to see if I could get consistent groups at that distance. Honestly I don't shoot enough to try those long shots with any confidence.