Olddog,
If I'm reading you right, NONE of the gauges would close.
The field is even larger than the no go, so that won't solve anything.
It sounds like your headspace is at or below minimum, especially since the live rounds chambered without issue.
Since you have access to the DPMS BCG, try swapping them and checking headspace on both.
Your chamber/bolt combo may be right at minimum and may pass with a different bolt.

