M16A4 Buttstock In terms of utilizing iron sights the longer barrel and fixed front sight gives an extended sight radius which makes it easier to shoot precisely. just one information place, I picked up a handful of salty used P&S M4 RAS's from Thoroughbred for $150 ea. yeah, not KAC, https://knightsarmamentras97306.estate-blog.com/29037040/helping-the-others-realize-the-advantages-of-m4-ras