I have to load my 54 grain charge of RE22 into the 7X57mm Mauser case in two increments. I trickle in about half the load, then tap the case about 20 times with a screwdriver handle, then load the second part of the charge very slowly, and then tap it to settle it also. This leaves me just about 1/4 of the length of the case neck open to start the bullet. Obviously, this is a compressed load, but it is very accurate and uniform in performance.

You might consider purchaing a long drop tube to use to get more powder into a case, or switching to a ball powder that has about the same burning rate. Some powder compression is OK, but it can be overdone. DON'T compress to the point that bullets back out or case shoulders expand!