From over at WRSA we find this link to WeaponsMan on accuracy and precision. The entire article (not long, either) is well worth reading, but I think I can summarize it for you in this quote and in the diagram following, and with my emphasis in bold:
The percentage of shooters that can outshoot their firearms is incredibly small. Shawn [read further] has made a habit of demonstrating the practical long-range accuracy of a rack-grade service rifle is considerably better than the specifications demand, or the average operator (in the sense of “one who operates a rifle” not “wannabe SWAT assclown”) can deliver.
And here’s the superb illustration:
With its accompanying caption, “It seems illogical, but for a combat weapon, (c) might be more desirable than (a). And even (d) might work.”
Indeed. Right off the bat, this made me think of the great LtCol Jeff Cooper of Gunsite fame, who several times in his priceless “Commentaries” spoke about just this subject. He referred to the problem as “PII,” that is, a “Preoccupation with Inconsequential Increments.” The topic appears HERE and HERE, but most especially from the standpoint of this post HERE:
In rifle work group size is of some interest, but it is by no means the critical consideration that some commentators seem to deem it. It is well to remember that a rifleman does not shoot groups, he shoots shots. A tight group is nice, but one must not fall into the error of PII (Preoccupation with Inconsequential Increments). I have shot a great deal in a long shooting life, and I have only once encountered a rifle that would not shoot better than I could shoot it. (That was a 32-20 lever gun which had been allowed to rust and then scraped out. In getting the rust out of the barrel, most of the rifling went along with it.)
Group size is unimportant, unless it is very bad. If you can hit a dinner plate, first shot, every time, under all conditions, at 100, that will do.
Sound familiar? It ought to. As usual, the old man was right on target, no pun intended. And that was written back in 2000. A standard M4gery today or AK (believe it or not), and most certainly a FN FAL or G3 or M1 or M1A or M39 or K98k or K31 with milsurp or off-the-shelf commercial ammo will provide the vast majority of us with more inherent mechanical accuracy than we can use or appreciate. The answer to the problem is, of course, to get out on the range and practice. Get off the bench, get into position and put yourself to the test on a six- or eight-inch circle at 100. Because, more likely than not there will be a test in the future.