What load are you using if you don't mind me asking and what is a JLK? My 6.5 x 284 shoots phenomenal groups with the 140 Berger Elite Hunter 140 grain with 46 grains of 4831 running at about 2800 fps but if I try to run it any faster than that it just starts to open up the groups. I have tried several different combinations but can't find anything that shoots as good as the load data I got from the factory.