To a 14 or 17 cal shooter, the .257's seem pretty large caliber.
To the 50 BMG shooter, anything less than the 40+ calibers seem little
more than pea-shooters.
Some writers have included the .243 to 30 calibers as Mid-size bores.
Seems like in many forums, however, the .257's to .270's are pretty
much left out with the exceptions of general rifle and reloading forums.
Since there needs to be a limit somewhere, this forum, at least for now,
will include the 6.5mm down to..................well, some out there are
attempting 10 cal and possibly smaller. Can almost see it now, the new
varmint hunters will be after bumble bees and dragon flies!