Well what is your criteria for accuracy?, and the number of rounds that must cluster within your accuracy definition?
Many are quoting gun writer definitions that three shot groups are the “Gold Standard”. If you really examine their motives, Gun writers get paid a flat fee for an article, so whatever justification they use, it all comes down to increasing their paycheck by decreasing the amount of labor to get it. Since our culture is the creation of advertising bureaus, the shooting public generally believes that the “Gold Standard” for accuracy is three round groups, because these all wise Gun writers said so. However articles in the popular press do contain rather funny results due to the lack of testing. The writers for Handloader regularly shoot three shot groups, and this month, one gun writer is claiming sub half MOA groups for a 35 Rem Marlin lever action. I remember an earlier article where he was claiming sub half MOA groups for cast bullets fired in a 30-30 lever action. If you are a heavy dope smoker, you might believe that these lever actions are ½ MOA accurate, but what you are actually seeing is the distortion caused by small sample sizes. Whatever data the gun writer is presenting is not a true measure of the capability of the gun or the ammunition. Larger sample sizes do show larger groups because the chance of a 1:100 event is larger, but you are not going to see enough rounds fired down range in any print article to determine the inherent accuracy of the weapon, or the load. And you the reader, just love that. Gun writers traditionally cull “flyers” out of their groups anyway, because they are biased to report wonderful results. They are under great pressure to make the weapon they are shooting the absolute best, rooting tooting shooting iron ever built. That is, if they want another commissioned article. Gun writers are already coming up with excuses for one shot groups, so called “cold bore” accuracy, and after that will be “virtual accuracy”. Virtual accuracy will consist of what the Gun writer dreams in his head, at his keyboard, for what he thinks the weapon will do.
For smallbore, each match is based on two 20 round targets. In a 160 round match, there are four 40 round matches to be shot. I would say, you want to know at least how your rifle shoots for 40 rounds if you want to be the winner of a match. Your rifle and ammunition better be shooting consistently for all 160 record rounds if you want to win the aggregate. Highpower rifle, each match is 20 rounds, 20 rounds standing 200 yards, 20 rounds sitting rapid fire 200 yards, 20 rounds prone rapid fire 300 yards, and 20 rounds slow fire 600 yards. You get bragging rights for winning a match at the Nationals, and of course, you want to win the 80 round aggregate. It has been said correctly, you win standing and lose prone slow fire. Accurate shooting while standing is more of a test of the shooter than the rifle and load, but get out to 600 yards, and your rifle and load better be very accurate. And your rifle better be holding its zero by the time you get out to 600 yards, you have already put 60 shot for record through the thing by the time you set your equipment on the line. I have heard good shooters state that they want a rifle and a load that as a minimum, will shoot half the size of the X ring at distance. The X ring is 6 inches in diameter at 600 yards, which is 1 MOA, a rifle and load that shoots half the size of the X ring will have to shoot under ½ MOA. That is a lot to ask of a rifle and cartridge.
The more you shoot, the more you find that most internet claims are based on small groups and limited sample sizes. A shooting bud of mine, who shot with Larry Moore, a Wimbledon Cup Champion, asked him “just how many rounds do you need to fire to have confidence in a load?”, and Larry replied :”about 20,000”!. Larry tested every service rifle from after WW2 to the 1960’s at Aberdeen Test Ground, so he had a lot of free ammunition to shoot, and to observe the performance characteristics of both rifles and ammunition.