The .375 Ruger is a rifle cartridge co-developed between Hornady and Sturm, Ruger & Co. in 2006. The .375 Ruger, released in 2007, was intended to improve upon the .375 H&H cartridge, the only cartridge of the same calibre.
Following two previously successful projects that resulted from the Hornady/Sturm, Ruger & Co. partnership (the .204 Ruger and .480 Ruger), the pair decided to develop a cartridge to outperform the .375 H&H cartridge. Unlike most cartridges, the pair decided to design a unique case for the .375 Ruger, while also using relatively heavy bullets (250gr or more) for the new cartridge.
The .375 Ruger is sold as a hunting cartridge, and one which has been designed to avoid the flaws that its rival cartridges suffer from. The first firearms to be chambered for the .375 Ruger were, unsurprisingly produced by Ruger (namely the Ruger M77 Hawkeye). The subtley unique design has gradually become popular among other manufacturers, with other companies producing .375 cartridges and firearms.
As mentioned above, the most unique aspect of the .375 Ruger is that it has an entirely unique case, one which lacks a rim. This means that the .375 Ruger has a larger capacity than the .375 H&H (around 6.4 cubic centimeters) and can therefore use more propellant and hence produce higher muzzle velocities. This case is capable of withstanding 62,000psi.
The cartridge neck tapers down to the .375in diameter bullet at an angle of 60 degrees. Testing by SAAMI in June 2007 recommended that the .375 Ruger uses a 1:12in ratio twist, with six grooves in the barrel. Because of the .375 Ruger's relatively short case length, it can be used in firearms originally chambered for smaller calibre cartridges without major modification to the receiver.
The .375 Ruger was designed to outperform the .375 H&H cartridge. Below are Hornady's official figures for the .375 Ruger's muzzle velocity and energy.
|Name||Muzzle Velocity (FPS)||Energy (ft/lbs)|
|250gr GMX® Superformance||2,900||4,668|
|270gr SP-RP Superformance||2,840||4,835|
|300gr DGS® Superformance||2,660||4,713|
|300gr DGX® Superformance||2,660||4,713|
These figures are about 150FPS better than those of the .375 H&H cartridge, suggesting that the pair acheived their aim of improving upon the former cartridge.