Vapdog and James B.

There is a section in the Speer manual either 11,12 or 13 that talks about "Modes" in external ballistics. The 3 phases are Modus violentus, modus medius, and modus terminus, if my memory serves me. It may be in a Nosler manul for all i can remember. But I rember reading it and being set with that "AH HA!" response. It seems that a bullet/barrel combination (and the various combinations of powder/primer/case/COl with in a bullet) produces flights of rotaional harmonic varibility. As I read and understand it some Modus violentus phase extend from 0-75 yds. on average, and the medius75-200, and terminus 200 out. SOME rifle/barrel/bullet combinations have an extended violentus ranges extending out to 125 yds. So the 100 yd range group will concievably be rotationaly varible more than the medius where the bullet settles down and the rotational harmonic becomes stable throughout the entire flight path of the bullet. Remember that the bullet is not shooting flat and in a line, but a spiral within an arc. harmonics are easier to judge when all things are straight and linear, but rotational issues throughout an arching flight get really complicated.

NOW, this may be a theory, but I believe that is why the Match bullets work over several ranges because the shape/jacket combos "dampen" the harmonics of the barrel/bullet combo. My 165 g SGK loads show this very thing, larger MOA at 100 yds and smaller groups at 200 yds. I shoot them at .70 MOA at 100 yds, and .35-.40 at 200 yds. So it explains my findings.

HOWEVER, there are probably more varibles I am not taking into account. MY 200 yd group BTW is in the RUGER ACCURACY forum on the 1 or 2nd page.

Dana