Lieutenant Colonel George V. Fosbery, VC approached Webley & Scott in 1900, having patented a design for an automatic revolver (a modified version of the Colt Single Action Army), whereby the recoil energy produced by the revolver could cock the hammer and rotate the cylinder by sliding the action, cylinder, and barrel assembly back on the frame. Webley developed the design further and created the Webley-Fosbery in 1901.
Using the recoil of the gun to move the cylinder and barrel back on the frame the cylinder, by virtue of a pin fixed underneath the cylinder, would rotate to the next chamber. The slider, which moved the top-half of the gun in its entirety, would also cock the hammer via a pivoting lever. The safety (a novel feature for guns at the time) would lock the slider, preventing the trigger being pulled and the slide from moving.
The cylinder did have the potential to sping backwards. To prevent this Webley designed a spring loaded stud which followed the grooves at varying depths. This design, however, was replaced (being seen as an overly complicated solution) with a fixed stud, with overshoot grooves cut into the cylinder. The grooves were made completely smooth to produce a smoother operation.
The Webley-Fosbery followed the traditional Webley reload system of a break-frame. The hinge was located above the slide, allowing for the slide to be cleaned out - a common problem for the Webley-Fosbery, as it relied upon the fine tolerances of the mechanisms to work at all.
The Webley-Fosbery had been intended for use with the British Army (and specifically the Cavalry), hence the .455 Webley MkII cartridge (the regulation calibre issued by the British Army) was the intended cartridge for the Webley-Fosbery. This was shot from a six-shot cylinder.
Later models would use the .38 ACP cartridge, in an eight-shot cylinder. These were intended for competition rather than military use.
Although intended for use with the British Army in 1901 and beyond, in particular the Cavalry, the Webley-Fosbery did not become standard issue. A few examples did see war action however (British Officers were, at the time, allowed to buy their own side-arm, as long as it shot .455 calibre) in both the Boer War and the First World War. It was during the First World War that the Webley-Fosbery received a reputation for being un-reliable and prone to jamming, due to the conditions of the trenches. The Webley-Fosbery required clean conditions, without the potential for dirt to get into the mechanism, rather then those found in the trenches in France in 1915. Outside of war, the Webley-Fosbery acquired a reputation for being very accurate, with the recoil, rather than trigger, turning the cylinder which meant the shots were smoother.