I like to shoot my rifles with clean—very clean—barrels. But I know that that rifle won’t be doing its best until it has been shot a bit. The precise number of shots varies from rifle to rifle and that’s a topic for another day.
But here’s a good demonstration of how the first shot from a cold, clean barrel will hit to a different point of aim. As you can see, after the first shot with both Sakos and with the Weatherby the groups tightened up significantly and hit to the same point of impact.
The most notable shift after the first shot was with the Sako A7, which put its first shot a good two inches below the subsequent 0.8725-inch group. But in all cases, following the first shot the rifles gave me nice sub-MOA three shots groups after that first fouler went down range.