This type of firearm designates a specific, and now largely obsolete, caliber. The “bore” refers to the diameter of the barrel’s interior, measured as the number of lead balls of that diameter required to make one pound. A four-bore rifle, therefore, has a barrel diameter large enough that only four lead spheres of that size would be needed to equal one pound. This translates to an exceptionally large caliber, significantly greater than even most modern high-powered hunting rifles.
Originally developed in the 19th century, these massive firearms were primarily used for hunting extremely large and dangerous game, such as elephants and rhinoceroses. Their immense stopping power was crucial in such pursuits. The substantial recoil, however, made them difficult to handle and impractical for most other shooting applications. This, combined with advancements in smaller, more efficient cartridges, eventually led to their decline in popularity. Though rarely seen today outside of museums and collections, they remain a testament to a particular era in firearms development.
