[Unclenick]

You're welcome. You can do a lot in Excel. The only thing it lacks that I keep Mathcad around for is automatic unit tracking and conversions. In Excel you have to handle those tasks for yourself.


Stubbicat,

I think you'll find the actual weight of the case is almost always the least significant factor. It is helping identify tooling that I use it for. A good rule of thumb is that, if the outside dimensions are identical (a necessary condition for weight to reflect internal capacity proportionally), then a 1 grain difference in case weight will correspond to a charge weight error of between 0.06 and 0.07 grains of powder charge. A good load should be able to go at least ±0.3 grains of powder without changing POI (and many stick powder loads will go a good deal wider), so that would correspond to 4.3 to 5.0 grains of brass weight if the external dimensions are matched.

That said, if you start actually measuring internal case capacity, you often find it varies less than weight among a range of cases. That's because of the multiple tooling and brass slug runs. No two setups seem to produce exactly identical dimensions. So, by sorting by tooling you usually do have a fairly identical set of outside dimensions and difference in weight is then more reflective of capacity. Notice, however, that even for Winchester, one set of tooling doesn't typically produce much difference in weight. Somewhere around a grain to a grain and a half. Usually less than 0.1 grains powder charge equivalent.