The rifles now referred to as “assault rifles” came to be in the latter years of WWll, when the Germans found that the full-house infantry round, the 8x57mm Mauser, was uncontrollable in a rifle-weight shoulder-fired weapon. The devised the MP-44 “Sturmgewhre”, a rifle featuring select fire and firing a less-powerful cartrige, the 8x33mm. Mikhail Kalasnikov applied the concept to his AK-47. The definition of “assault rifle by the military is a select-fire rifle of INTERMEDIATE POWER.
The M-14 was unmanagable in full-auto fire. The old BAR was capable of select fire but tipped the scales at 20 lbs.
I have seen AR-15s used in high power rifle competitions at 600 yards but it requires an 80gr. bullet with a different rate of twist in the barrel rifling. There is a difference between punching a hole in a piece of paper and making certain that SOB 600 yards out is down for the count. The M-4 is a cut-down M-16. In making it more compact for urban warfare, a good deal of velocity was sacrifices, further reducing the effectiveness of a marginally effective round.
It is difficult to build a rifle that will do all things for all people but in the end, ya gotta have enough gun
My understanding is that since WWII, marksmanship was considered less important than firepower. Standard military doctrine for small-units revolves around suppressing the enemy with high firepower while a second team maneuvers in close for the kill. If further out, then you call in air strikes or artillery. But generally you try to avoid a marksmanship contest.
Of course, according to the NYTimes, Afghan (and Taliban) marksmanship is terrible:
The select-fire feature was dropped from the BAR design fairly early. My Father-in-Law carried one in the Marines in Korea. Full-auto only.
Excellent point! If I remember correctly, the current 62 grain bullet will fracture at the cannelure if it impacts with enough velocity, which at least gives you two wound tracks from each hit. The M-16 will therefore have a better chance of getting the job done (in terms of terminal ballistics) in any given situation. Maybe we should at least look at putting M-4 buttstocks on flat top M-16s and split the difference (the Canadians have or had a model like that)...