We do this with 10 meter pellets as well, on a pistol we saw group size range from 5.9mm to 9.5mm, the pellet is 4.5mm. The right batch can make a big difference, in pistol with standard scoring (rifle typically does decimal) it moves a 9 to a 10 with the same hold, could be 1-2 percent in score with will make or break you.