I refer to any back up non-glass sight as Back Up Iron Sight ( BUIS) .
I know some guy's like to leave these on for just in case moments . My only concern is that without QD mounts in place, what are you going to do. I've used the Larue QD mounts and been impressed with how much accuracy the have when you return the scope tot he rifles exact same location.
They are pricey though!
Nikon Pro Staff