Glenn, 
I'm a firm believer in controlling run-out.  A person can pay good money for a bullet mold but if you start the bullet out crooked in the tube, then it's a waste.  I ran a test (for what it's worth) with my 40-70 SS.  I shot an 8 shot group using loads with low run out, circled it and then fired 4 more shots with high run out and only 1 of the 4 was inside the original group.  Not much of a test but it made me start watching run-out very closely and I think it helps.  I seem to get a lot of run-out with certain calibers and believe some of it has to do with the dies and seating stem alignment. Here's what I use to measure run-out and I use it on all calibers when I'm going to shoot a match.  Bob
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