Teeder,
It's hard to explain this without using my hands, but.......it can appear the partition is forward on heavier bullets than lighter bullets of the same caliber, but proportionally they can be in the same position from one weight to the other.. A heavier bullet is longer, but proportional to it's length it has the same amount of lead in the front and rear halves.
II have sectioned all the 7mm bullets that you have pictured, and have seen the same thing. The partition of the 160g is obviously further forward compared to the 150g.
Have never sectioned a 338 cal 210g bullet though, and the extra thick jacket is interesting!
