The 120-123 class won’t group what is going on

[grayfox]

The 120 gr bullets have a fatter, tangent ogive and so should not expect them to load out to coal's of the 123's, like Hornady black for example. The 123's were designed with a more like secant ogive and have a longer taper.
And from another forum (6Arc) I've found that most bullets seem to do well at 60-100 thou' off the lands. There's an accurate shooter article talks about that. The "bestest", "absolutest" benchshooting length may go up to the lands or real close to it but that advantage falls off every 100 shots due to throat erosion. The 60-100 range offers a long-time depth that shoots very nicely.

So if your 120 eldm sits at 2.230 on the lands try it at somewhere 2.180-2.170. Just be aware that the fatter ogives will seat shorter than the 123's.

I measure all my bullets to find out where they hit the lands, even for other calibers (ok I don't worry so much about the 223's). Assume nothing from one bullet to the next.