Concentricity Issue on 6 Dasher

[MJT]

I was checking the concentricity of my 6 Dasher loads (Lapua BR turned, Berger 105g 6mm hybrids). The brass checks out almost perfect around 1/1000 using a Sinclair concentricity tool, but loaded rounds are off by as much as 5/1000 measuring off the ogive. No expander ball, Lee #2 case holder, Wilson full length seater. Case holder and seater are clean.

Not sure what to look for. I might try getting a new shell holder, or trying a new batch of bullets. Any ideas?

 

[WillyTP]

Since you said you're running hybrids I would suspect the stem in your seating die is not matching the point of the bullet well. The meplat and nose of the bullet will bottom out in the end of the stem. Check it by pulling out the stem and placing a bullet in it to see how well or not they mate up. From there if that's the problem you have a few options depending on the tools and equipment you have access to.