The .505 Gibbs cartridge was designed by George Gibbs in 1911. The cartridge was originally known as the .505 Rimless Nitro Express. The C.I.P. refers to the cartridge as the 505 Mag. Gibbs in their publications. It is a.50 caliber rimless bottlenecked cartridge intended for magazine-fed rifles.
General information
The.505 Gibbs has a case capacity of of water. This cartridge was originally loaded with of cordite and bullet at for of kinetic energy. While the.505 Gibbs has a greater case capacity than most modern cartridges, it is loaded to lower pressures. The C.I.P. recommends a pressure of for the cartridge. As.505 Gibbs was intended for hunting dangerous game in a tropical environment and due to the temperature sensitivity of cordite the lower pressures provided a greater safety and reliability margin. The.505 Gibbs has a unique bullet diameter of while most other.50 caliber bullets have diameters of. Barnes Bullets and Woodleigh Bullets are a few of the bullet manufacturers who produce component bullets for reloading in this caliber. Woodleigh Bullets does not recommend impact velocities of over for their.505 caliber 600 gr. Weldcore bullets. George Gibbs Ltd. continue to manufacture.505 Gibbs rifles; other premium dangerous game rifle makers, such as Hartmann & Weiss and Westley Richardsbuild expensive but thoroughly reliable.505 Gibbs rifles on Mauser 98 actions. Ceska Zbrojovka currently manufactures the Safari Classics rifle for this cartridge. Doumoulin Herstal SA of Belgium offers the cartridge in their White Hunter model. As of 2019, Federal, Kynoch, Norma, and Swift are offering factory loaded ammunition in.505 Gibbs. Bullets for reloading are available from Barnes, Cutting Edge Bullets, North Fork Bullets, and Woodleigh Bullets.
Design and specifications
The.505 Gibbs is one of the most voluminous cases designed. The large volume was required as the cartridge was designed to burn cordite as its propellant. The C.I.P. has published specifications for the cartridge. The C.I.P. recommends that commencement of rifling begin at. Bore diameter is given as and groove diameter is. The C.I.P. recommends a five groove barrel contour with each groove having an arc length of and a twist rate of one revolution in. The recommended pressure for the.505 Gibbs is.
Sporting use
The.505 Gibbs is a niche cartridge designed for hunting heavy, thick skinned dangerous game animals, such as cape buffalo, elephant, and rhino.
