Introduced in 1912, Holland & Holland designed the 375 H&H for use in its double rifles intended for hunting the largest species in Africa. It was perhaps the first such chambering originated as a smokeless-powder loading, not a blackpowder cartridge later adapted to smokeless as the various Nitro chamberings were. Considering the intended application, H&H designed the guns and ammunition to work in the harshest of conditions. Initially, it kept pressure low (47,000 psi), to prevent overpressure and case sticking on the hottest of days, and tolerances large, to assure rounds would freely chamber and fired cases would freely extract even when the chamber and ammunition might be dirty. Subsequently, with improvements in propellants, concerns about over-pressure at high temperature have moderated and working pressure for the 375 H&H is now established at 62,000 psi, which is close to the high end for modern cartridges. As such, it offers significant performance. Long recognized as one of the all-time greats for African hunting of large and dangerous species, the 375 H&H has the advantage of delivering a reasonably heavy bullet with sufficient velocity and doing so without generating undue recoil. Most shooters can learn to handle it well. That is not necessarily true with chamberings of 40-caliber and larger when delivering similarly effective bullets. Several bullet makers now offer extremely efficient long-range bullets in 0.375-inch diameter. This adds a whole new facet to versatility of the 375 H&H. It is fascinating to compare extreme long-range potential of this round to cartridges such as the 338 Lapua. When each is loaded with the best available bullets; the 375 compares surprisingly well. The 375 AI version would amaze most shooters because it comes oh-so-close to doing anything the 338 Lapua Magnum can do. This was the original belted-magnum case.