I have a 26" krieger, using Somchem S365. Winchester brass and Nosler 70gr BT. Neck tention is 0.003. S365 is an extruded stick powder as H4350 Quickload gave me a node on 3680fps, I could only get 3640fps. Upping the charge gave me a lower speed. This was on federal 210m primers. So I changed to Federal 215m magnum primers. On the same 48gr charge it gave me 3800fps. A full 160 fps more on primer swop. Should I stay with a good case fill and magnum primer or go to a faster powder with less case fill but standard primer?