I am hoping someone could help me once again.  

I currently have an ACOG TA01NSN on an ARMS 19S mount and a KAC 600M flip BUIS mounted on my flat top.  I want to move my ACOG rearward a notch more on my flat top, but the ARMS mount hits the KAC BUIS so there's one notch left between ARMS mount and the base of the BUIS on the flat top upper.  

The reason I'm asking is because I have an LMT SOPMOD stock and want to take advantage of the cheekweld on the stock and not on the buffer tube.  My current set up makes me weld on the buffer tube to get a "whole" sight picture thru my ACOG.

Which flip up BUIS would allow the ACOG to be mounted furthest to the rear and not have a vacant notch between the mount and BUIS?

Thanks for your input.

Frontsight    

Troy has one of the lowest profiles in the Rear BUIS market. It's what I use, and I butt my Compact ACOG in a LaRue mount right up to it. I also want a proper cheek weld and sight picture. Not asking too much.

Give the Troy a try. I don't think there is anything lower out there.

Tack

I have a question about the Troy rear BUIS.

When it is flipped up, how far away is the sight from your eye compared to a standard A2 iron sight? I have been looking at pictures, and it seems like the sight would be about a half inch further from your eye compared to sighting through A2 irons.

Anybody who owns both have input on this?

If it IS further away (??) is it noticeable when you look through the sight?

Tack,

Thank you for your input.  I will give the Troy BUIS a try and see how it works for me.  

So the base of the Troy BUIS is lower than the base of my KAC 600m BUIS?

Frontsight