You're in position to verify what I've said here all along -that concentricity gages(Hornady, H&H) mask runout. The reason your deviation seems to go up back on the necks is that the indicator is further from the pinned bullet nose. Further back on the body you would see even more, and further toward the bullet tip would show even less -on any ammo -with that gage.
If you measured that same ammo on a Sinclair roller/v-block type gage, you'd find that your runout is actually greater than you think.