Case weight has nothing to do with internal capacity . The machine error and the brass quality can change the total weight.. With a Dasher and a small case capacity. .2 tenth of internal case capacity difference I get as much difference as 2'' of vertical at 1000. LarryT-REX said:Has anyone tried to determine what case weight variation is worth on the target? I have seen a lot of claims over the years that it is important and other claims that say it is not important but I can not remember anyone that presented meaningful data either way. The new F Class target has touched off a new arms race and is pushing accuracy to a new level so the answer for F Class might be different than a less demanding target.