by Hoot » Sun Aug 30, 2020 7:55 pm
Vertical stringing as the groups get smaller, are almost always a manifestation of varying velocity. The smaller the group, the more noticeable the stringing becomes, even though its still a great group. That just means you did everything you could to ensure precision. The velocity difference would be the only variable that is hard to control in this caliber. Barrels swing from low to high as the bullet races down the bore.The only solution, if you were chasing BR results, would be to tune the barrel so that the muzzle is rising past zero as the average velocity bullet emerges. The slower bullets would normally drop more but they exit the barrel later, when the muzzle has risen a little more. Its called positive compensation. It is accomplished most frequently by adding an adjustable tuner to the muzzle, to vary its effective length. It is also the reason why shooters often see a change in POI with versus without a muzzle brake or flash hider added. The smaller (more flexible) the barrel diameter is, the more it whips. Less noticeable with a bull barrel but still there.
Hoot
In Theory, there is no difference between theory and practice. In Practice, there is.