4 bore

Common card · No. 293298

Four bore or 4 bore is a black powder caliber of the 19th century, used for the hunting of large and potentially dangerous game animals. The specifications place this caliber between the larger 2 bore and the smaller 6 bore rifles. This caliber was the quintessential elephant gun caliber of the black powder safari rifles. The caliber was also used for the Coffman cartridges used for starting large aero engines such as the Rolls-Royce Griffon as used in the later Marks of Supermarine Spitfire.

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