There are a wide variety of BUIS types available, both flip-up/fold-down and fixed.
After co-witnessing, if either the optic or the BUIS system gets bumped off-zero, it will be instantly apparent to you because they'll no longer be in alignment.
So leave the BUIS
alone and keep it installed in the rear-most slot on the mounting rail.
It has a 16-inch M4 barrel with MOE black Gen2 BUIS
brought in the New Year exactly the same way he did 12 months ago, by winning the Resolution Run on Newcastle Town Moor.
may have came out on top in his latest race, but he was not always at the head of affairs during the sixmile contest.
continued his run of success with victory in yesterday's Watergate Trail Race at Lobley Hill.