Wyo, I have no experience with the tool, but meplat size has a LARGE influence on BC. Approx 70% of a bullets "sleekness" comes from nose shape, and much of that portion from meplat width. It is I think, a shock wave multiplier, ie. when you double the meplat width from say .005" to .010", the drag increase is geometric rather than linear. Hence, the big change in BC you experienced. It is the devil's brew I suppose; you may improve BC uniformity but at what expense?
ON the other hand, I may be totally out of my mind on the subject.
[ 02-27-2004: Message edited by: MAX ]