What primers are you using ? Speer has found that that powder works best with their CCI 300, rather than their magnumn 350's.
Are you seating with one pass and crimping heavily with another ? A heavy, or very heavy, crimp is often necessary.
My favorite loads are 20 grs. of 2400 over a 240 gr. Hdy XTP or 19 grs. of the same powder with a 250 cast, SWC. Either load shoots 1.5-2 inches at 25 yds with iron sights from my 4 inch Smith.
Funny you mention primers. I have beat the bushes forever.
Federal also uses a 150 primer. I use nothing else.
How funny is it that back in the 70's, I found the mag primer was wrong in the .44?
But crimp has little to do with powder burn. Case tension is needed. Soft lead that gets sized when seating is an atrocity.
