Re: Define accuracy
The objective of tactical shooting is not to get the best possible performance from a system, but to be able to make the system perform well on demand.
When all best and worst groups average 1/4 MOA, or you shoot five consecutive five shot groups at 2" at 800 yards, then I'll concede you may have a 1/4 MOA rifle. Problem is, in order to to do that, the best the rifle can do must be 1/8 MOA and the best its ammo can do must also be 1/8 MOA. When this happens the result on target will be groupings right around 1/4 MOA (assuming, of course, that you can find ammo that precise and that you can hold equally well).
At close range good groups are easy to make. If you like bugholes, shoot at 100 yards from the bench using flat-based bullets. That should put you well under 1/4 MOA with a good rifle. Whether one measures the result from center to center or from the outside edges doesn't really matter either (except mathematically, if, for example, you want to derive the theoretical size of a proportionally larger group from a smaller one). Whether we shoot a few cold bore shots over a few days, or a bunch of rapid-fire shots on a stage, we're always shooting a group anyway - even if we don't 'shoot groups'.
For our purpose an accurate rifle is one that puts a bullet hole as close as possible to the position of the sights (or the reticle) everytime. If the shot ends up at four o'clock, and you called it low and right, then you've got an accurate rifle. An accurate rifle is important because the more precise its ability to place the shots the more influence the shooter's correct hold will have on bullet placement. And that's what we strive for. Consistency may or may not be a separate issue...
The bottom line is that if the holes appear on paper where the sights were when you pulled the trigger, that tells us what we need to know. What you call it or how you measure it is a distant second.
And the rest is marketing....
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