Quote Originally Posted by AR15freak View Post
I never understood why some would want a lower 1/3 co witness. I only want to have one point of aim when I look through the scope, not two separate ones. BUIS means backup.. Point is that iron sights used to be the primary sighting system for fighting rifles, but now they are used more as a backup option should your red dot fail. Since the human eye picks up the red dot quicker than an iron sight post it makes sense to use it as your main sighting system.. However since the BUIS are in a fixed position on the rifle and don't move, you need to sight them in first, then align the red dot to the BUIS.. I have always done it that way, it was taught to me that way, and I believe that is the right way.. however others with far more experience than me may do things differently. If it works then more power to them.
on lower 1/3, Me personally, I do not like flip up sights. I have some on my work gun because I am told what to use. My personal gun has Troy HK style (Rounded hood) battle sights fixed. I like them much more than std ar front sight post (V type). Having fixed front and rear, lower 1/3 is much better or has a cleaner view. It works for me and i really like it. It may not or does not have to work for you but you may want to try it. Not just a few shots but run it for a while.

IMO, co witness does not mean they meet eachother when sighting, it simply means, viewed together (inside the RDS window).