Testing, testing...

[stanc]

A brief comment on case capacities: I would rather have a bit more than is strictly necessary, for two reasons: this provides a margin for accommodating very long bullets (e.g. lead-free tracers) protruding back within the case without raising pressures; and it also allows for the possible use of a polymer case (with metal base) which will be thicker and will therefore reduce capacity.

I fully agree with the need to plan for use of tracers. In all my discussions about alternative cartridges, nobody else has ever considered that need. However, I would prefer to go with the smallest brass case compatible with that requirement.

I see little reason to be concerned about the possible use of plastic/metal cases. I mean, they've been working on those for how many decades, and have yet to produce a viable product.