Quote Originally Posted by Disciple View Post
My view through a lower 1/3 mounted Romeo 4 or 5 to a midlength-FSB puts the bottom of the window almost perfectly even with the shelf of the front sight when the red dot is at the tip of the sight post. I think that is a useful reference alignment if I don't have time to raise the rear sight.

I haven't tried shooting with a fully occluded red dot. Is it better to keep both eyes open and ignore the sights entirely, trusting motor memory of the alignment, or roll the gun and try to index off the the handguard and barrel? I probably couldn't hit the broad side of a barn in either case.
That would be the modern-day equivalent to the Armson OEG of Son Tay Raider fame. It was designed to shoot with one eye open, and the same principle applies to an Aimpoint with the front lens cap closed.

It's been 20+ years ago that I had an Armson OEG on an AR carbine. It was cool for a "quick-shoot" CQB type of range (the dot was rather large, like 4MOA) but an actual non-occluded red dot was more accurate. Back then I shot a good deal more than I do now and noticed the difference, more so the further out you went.