Dont use a berger if your looking for monolithic performance. Dont use an eld-x close range and hope for 98% weight retention.
Understand your bullets ballistics and shoot with in them.
Bergers don't leave a great blood trail cause you have a pencil hole and then they explode and fragment.
Ran into similar issues with a cooper. Had to switch powders retumbo, RL-26 and VV n565/570 was able to get that extra 100-150fps but h4350 was probably the best temperature/overall load. You could consider have a gun smith re do the chamber.