The flat spots are your nodes. I usually pick the center (if their is a clear center charge) and fine tune from there. If it is a hunting load, I then adjust the seating depth and I am done. For example, I would 33.6 gr with the SST. I would then try seating at 3-4 different (+0.005, 0.010, 0.015, and 0.020" from the lands). Once I set seating depth, I go back and shoot 5 shot groups at the center charge plus/minus 0.2 gr. It would be 33.2, 33.4, 33.6, 33.8, 34.0 gr for the SST. What shoot the best there is what I would go with.

If you don't want to mess with seating depth, call if 33.6 gr and go have fun.

I am shooting a 223 ladder this afternoon. I will see what it looks like and post resu