The standard open iron sight aiming elements consisted of relatively coarse rugged aiming elements making the sightline suitable for rough handling and low light usage, but less suitable for aiming at small point targets. The tracks of the rear sight obstructed the view to the sides during aiming. The sights were designed with distant area fire targets like charging horseman units in mind, so the standard iron sight line could be calibrated for very long ranges. Military doctrine in the late 19th and early 20th centuries considered firing at distant area targets, where an officer would call out the range and the soldiers shot in volley, normal.
