I think there is a balance between sabot
thickness and bullet diameter, when
putting them out high speeds,in rifled.
What I mean is I think in your 458 example the
sabot should have thinner sides with say a
375 cal bullet.That is why I am going to see
where I can find 12ga sabots taking 58cal bullets
or maybe 620 cal.I have pictures on soon of
this idea. I think for high speeds there is
such a thing as to much plastic.Ed