Thread: Accuracy at 100 vs 600 (example). Variations in accuracy at different ranges

My copy of 'The Sharp Shooter' explains it as all the bullets in a group actually spiralling in the same direction as the twist of the bore (x spiral) then due air pressure building on the tip of the bullets, because they are not flying completely in line with the direction of travel. This air rolling off on the opposite side to the x spiral initiating a y spiral.

So what this means is that bullets move away from the line of sight then move back and cross it and then disperse outwards again then straighten out of these spirals again but not before they have taken their dispersive effect.
To Quote Matt and Bruce Grant: 'The occasional extraordinarily good group which shooters preserve and show off is due to y error for the shots all combining within the circle of x error at the target. Ironically, a group from the same shots taken at almost any other range would show a wider dispersion'.
What I take this to mean is that a target shooter would need to have a box of ammo tuned for each range that they will shoot at.

A link to the original work of DR FW Mann https://duienforcers.wildapricot.org...unnCo_1909.pdf

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