Re: brass weight sorting
This has been an interesting 10 page read. There are some intelligent and qualified people here. The debate of capacity vs. volume has always been an interesting one to me. For my mechanically inclined mind it seems to me that a rifle is basically a combustion chamber. Internal volume would affect pressure, pressure in turn velocity. If you want to get consistent velocity you would need consistent internal volume. I tend to agree with the capacity crowd. Different weights can yield different volumes true (when extreme i.e. 7gr), but different weights can also yield the same internal volume (i.e. rim thickness). It will be interesting to see whether Monte's test confirms this.
There are other ways to determine internal volume that are more accurate than using H20.