You mean like when I fire form my dasher and dont do any case segregation and my extreme spreads are 10 fps When you look at the part of the case thats not occupying chamber volume its a very small percentage. With slower powders and heavy bullets 30" barrel case arbitration occurs long before the bullet exits the muzzle. In my previous post I was talking about (a given lot of cases) not brand. I dont think any one would mix brands of brass Would you? I think that your missing the point. Im not saying nor have I ever said that other case prep procedures dont biuld consistacy remember ( It all works together) But to say that case weight has no merit is wrong. I have sorted hundreds of Lapua cases And always find different lots within a lot out of 1000 cases