Small-bore refers to calibers with a diameter of or smaller. It may also refer to small-bore rifle competition. The medium-bore refers to calibers with a diameter between up to and large-bore refers to calibers with a diameter of or larger. Miniature bore refers historically to calibers of or smaller.
There is much variance in the use of the term small-bore, which over the years has changed considerably with anything under caliber considered small-bore prior to the mid-19th century. __NOTOC__
Small-bore competition Small-bore competition often refers to shooting competitions conducted with .22 Rimfire target rifles.http://compete.nra.org/documents/pdf/compete/RuleBooks/SBR/sbr-book.pdf Small-bore rifle NRA rule book
See also List of rifle cartridges Table of handgun and rifle cartridges
References
Historic small-bore Enfield, BSA and other Service, Training and Target rifles reference pages, with league competitions for such rifles
External links Small-bore rifle NRA rule book