I've always shot 180 grain core lokts with my 300 win mag with pretty good results, but no more. I went from an inch and a half group at 200 yards to about an eight inch pattern. I thought it was me or my gun, tried everything, couldn't get a better group. I ended up shooting a few rounds from a box that I had bought a couple years ago, and they shot great. I figured remington must be doing something different cause any of the newer boxes I've tried are not accurate at all. I tried federal premium nosler partitions and Fusion. The fusion worked great, I have been consistently getting 1 1/4" three shot groups at 200 yards. Also very happy with their performance in the field.