Ive been trying to figure through this all day - I just mounted a 3x magnified in front of my EOTech 511, and thus had to slide the sight considerably forward to the front rail...does it make sense that I had to re-zero (by a fair amount) with the new config?

Out of the box the sight was very close to zero right in front of my ARMS#40 rear sight.

I though the EOTech was pretty much calibrated to be dead-on parallel with the bore and youe eye position didnt much matter? Is there some parallax variable going on here?

Thanks in advance.

Ummm, the magnifier is supposed to be mounted behind the EoTech... That's problem #1.

#2, Be aware that sometimes the EoTechs do not hold zero well.

Thanks, thats of course what I meant --- mag AHEAD of/in font of the EOtech..Im not THAT much of a NOOB ;-)

Perhaps thats the issue (EOT needing regular re-sighting) and just a coincidence/not related to the new-config.

You moved your eotech for the original position it was sighted in at.