"One distinctive feature is a plastic or metal stock directly behind the action, which contains a recoil spring to reduce muzzle rise, especially during automatic fire"
"The carry handle is a popular feature."
"Hot gases from the barrel vent directly into the receiver to push the bolt carrier rearward"
"maintenance can be a little tricky and the rifle is not quite as reliable as earlier U.S. rifles"
"A cocking lever was omitted from the earliest models to prevent entry of dirt"
"The magazine release is on the right side of the rifle but can be switched for left-handed users"
"Current military magazines have 30 rounds, and are sometimes taped in upside-down pairs to speed reloading"
"The combination of high velocity and a fragile small bullet is more likely to cause incapacitating injuries than death by hydrostatic shock"
"A surprising minor weakness is that the barrel can wick water up into the barrel by capillary action"
"The system incorporates an adjustable dual-aperture rear sight that corrects for both windage and elevation"