I was zeroing a couple of unfired ARs yesterday. At 15y, for a 'make sure I'm on paper' sanity check, I'm about 6 inches low. OK, maybe it's the blem PA dot? Nope, the irons are 6 inches low also.
This is a 6920? the one that came without furniture? Fixed front sight, I put a full set of Magpul MOE and a MBUS rear sight on it, otherwise untouched.
In the same session, my M&P barely needed adjustment, so I don't think it's me.
Any thoughts?