EoTech / Irons Issue

[argonstrom]

I have an issue with my AR & EoTech: With the standard front sight & flip up rear (I don't know the manufacturer - looks like a popsicle stick & adjusts from 200 to 800 yards), it's on target, but with the EoTech (cowitnessing), it shoots a good foot+ low maxed out on adjustment.

I bore sighted the EoTech at home later & confirmed the above (didn't bore sight the irons), put a small riser under it and got it spot on. The flip up rear is now way off.

Has anyone had the same issue? What am I missing?

[Graves]

Sounds like the FSP needs adjusted.

[argonstrom]

It would need to be adjusted to sit below its base to get even close.

[Graves]

It would need to be adjusted to sit below its base to get even close.

Is it already bottomed out?

[BadShot]

Are you trying for an absolute or lower 3rd co-witness? And what range do you have your rear sight set at? Sounds like a matech rear BUIS.



Is that it?

[argonstrom]

Is it already bottomed out?

Not yet, but it would have to be somewhere in the upper third of the "A", if that makes sense.

Are you trying for an absolute or lower 3rd co-witness? And what range do you have your rear sight set at? Sounds like a matech rear BUIS.



Is that it?

I'm not sure what you mean (probably absolute, as I was thinking the irons & EoTech should be "lined up" or atleast hitting near each other), but that's the sight - it was set at 200.

[OgenRwot]

Yeah, adjust the front sight it should clear things up. My EOTech and BUIS don't line up perfectly but I don't need them to co-witness. The only reason I'm running BUIS is if the EOTech goes down. There won't be a red dot to worry about in that situation.

[BadShot]

Yup, sounds like you're trying to set up an absolute co-witness. That can be tricky some times, but shouldn't be this bad.

So generally the best way to do this is to sight in the irons (in this case you can zero them at 50m, which is the same as a 200m zero) and then align the EOTech with the front sight post. The inner dot should be sitting just ontop of the front sight post. If that isn't working for you, you can always pick up an EOT riser that will put the irons in the lower 3rd of the sight window.