Larry,
Interesting. First thing that comes to mind is that I don't really get a big puff of filler, that I can see, from the muzzle. I'd say normal little smoke for a cast load. Not what you get from 50/50 Alox/beeswax.
In the loads that I shot the best groups with the 6.5MS and the 6.5Swede I used AC bullets, not hardened. I have shot harden thought.
I'm wondering too my velocities were higher then yours the only differences being I'm using different buffer then that #47, my bullets are sized fatter, and my cases are crimped. I'm using Wolf primers and they are not exactly soft primers and on the hotter loads the are pretty flat, but not a 90 degree corner. With the 6.5MS I started off with LBT Blue Soft lube, later switched to my soap lube, but the Swede was always with my soap lube. One more thing, my gas checks were mine exclusively.
Joe