Six bore

6 bore
Type	Rifle, Shotgun
Place of origin	United Kingdom
Specifications
Bullet diameter	.919 in (23.3 mm)

The 6 bore, also known as the 6 gauge, is an obsolete caliber that was used commonly in 19th-century black-powder firearms.

The 6 bore is a .919 in (23.3 mm) caliber firearm, used both as a shotgun firing shot and solid projectiles from muzzleloaders and breech loaders, both in smoothbores and rifled longarms. Late breech loaders were designed to fire cartridges.

A 6 bore cartidge rifle built by W.W. Greener in 1891 for a southern African trekker called Viljoen, fired 1,750 gr (113 g) bullets at 1,550 to 1,600 ft/s (470 to 490 m/s). Three types of ammunition were supplied, hardened lead for elephants and rhinoceros, slightly hardened lead for buffalo and pure lead with a copper tube hollow point for lion.

Early 6 bores tended to be large muzzle loading shotguns that were used for wildfowling, whilst designed to fire shot experiences with dangerous game in Africa and India saw them loaded with solid projectiles, usually propelled by a double charge of black powder.

By 1850 the ivory trade was well developed in Africa and India, and muzzle loaded 6 bores were relatively popular, particularly for rifled weapons as opposed to smoothbores. As breech loaders and cartidge rifles came into vogue, the 6 bore's popularity faded in favour of the larger 4 bore, which became something of an industry standard, as it was a very popular choice of caliber for punt guns.

By 1880 conventional wisdom was the smaller 8 bore was a more practical caliber for hunting elephant, as rifles could be produced in more practical weights with more manageable recoil than the giant 4 or 6 bores. Despite this, 6 bore cartidge rifles and cartidges could still be purchased. The 6 bore was only made obsolete by the introduction of Nitro Express cartridges in 1898.

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Wikipedia