Possibly…. I am fairly experienced and never had those issues before and have zeroed a ton of rifles. Both my own in and out of the military and friends new to shooting especially after the summer of love quite a few co workers bought rifles with no experience. I am not an expert though and I would say I screwed up somewhere but that same day set up the same way put that EOTECH on my Bcm rifle and things were fine. Like I said I am happy with what they are doing for me not bashing sionics at all. Once I get it in hand I will take it out and go from there. I started the thread because I was curious what others thought. I may have been at fault. I originally thought that the optic must have been loose and checked it seemed solid but tightened it a little anyway. Tried my aimpoint I’ve had few years and know is good with the same results. Then put that back on the Bcm and was fine. It was pretty weird. But I may have over looked something stupid that would explain things.