Question: What cartridge was used in  a standard issue service pistol for the armed forces of the United Kingdom from 1887 until 1963
Context: The Browning Hi-Power BDA ("Browning Double Action") is a 9mm semi-automatic pistol developed in the early 1980s at the Belgian Fabrique Nationale arms factory in Herstal.  The pistol was conceived in 1983 to compete in the U.S. XM-9 Pistol Trials to select new sidearm chambered for the 9×19mm Parabellum cartridge that would equip all the branches of the United States armed forces.  Ultimately, the winner of the bid was the Italian Beretta 92F.  The Finnish Defence Forces accepted the weapon into service as their general service pistol under the designation 9.00 PIST 80 and 9.00 PIST 80-91.  The pistol was marketed in Europe as the HP-DA. The Astra modelo 400 was a Spanish service pistol produced by weapons manufacturer Astra-Unceta y Cia SA.  as a replacement for the Campo-Giro 1913/1916, which had also been chambered in 9mm Largo.  It was the standard issue sidearm in the Spanish Army during the Spanish Civil War and also saw service in Germany during World War II. The M1911 is a single-action, semi-automatic, magazine-fed, recoil-operated pistol chambered for the .45 ACP cartridge.  It served as the standard-issue sidearm for the United States Armed Forces from 1911 to 1986.  It was widely used in World War I, World War II, the Korean War, and the Vietnam War.  The pistol's formal designation as of 1940 was Automatic Pistol, Caliber .45, M1911 for the original model of 1911 or Automatic Pistol, Caliber .45, M1911A1 for the M1911A1, adopted in 1924.  The designation changed to Pistol, Caliber .45, Automatic, M1911A1 in the Vietnam War era. The Karabiner Model 1931 (K31) is a magazine-fed, straight-pull bolt action rifle.  It was the standard issue rifle of the Swiss armed forces from 1933 until 1958 though examples remained in service into the 1970s.  It has a 6-round removable magazine, and is chambered for the 7.5×55mm Swiss "Gewehrpatrone 1911" or GP 11, a cartridge with ballistic qualities similar to the 7.62×51mm NATO/.308 Winchester cartridge.  Each rifle included a 6-round detachable box magazine with matching stamped serial number.  A charger is used to load the magazine from the top of the receiver. The Beretta AR70/90 is a gas operated self-loading rifle chambered for the 5.56×45mm NATO cartridge, and is the standard issue service rifle of the Italian Armed Forces.  The weapon is also designed to be fitted with a rifle grenade, and has grenade sights.  The AR series comes in many variants such as the AR90, with a wire folding stock, for use by paratroopers. The OTs-27 Berdysh ("ОЦ-27 Бердыш", Russian for "poleaxe") is a Russian semi-automatic pistol developed in the early 1990s by TsKIB SOO as a candidate to replace the standard Makarov PM service pistol in service with the Russian Armed Forces. The Webley Revolver (also known as the Webley Top-Break Revolver or Webley Self-Extracting Revolver ) was, in various marks, a standard issue service pistol for the armed forces of the United Kingdom, and the British Empire and Commonwealth, from 1887 until 1963. .455 Webley is a British handgun cartridge, most commonly used in the Webley top break revolvers Marks I through VI.  It is also known as .455 Eley and .455 Colt. The Viper Jaws pistol is a heavy duty single- and double-action pistol made in Jordan by KADDB and designed in the United States by the American citizen Wildey Moore, designer of the famous Wildey pistol.  Apparently this pistol is the standard issue pistol for the Jordanian armed forces, hence another designation—JAWS, or Jordan Arms & Weapons System. The SA80 is a British family of 5.56×45mm NATO small arms, all of which are selective fire, gas-operated assault rifles.  The L85 rifle variant of the SA80 family has been the standard issue service rifle of the British Armed Forces since 1987, replacing the L1A1 variant of the FN FAL.  The first prototypes were created in 1976, with production ending in 1994.  The A1 variant was significantly upgraded in the early 2000s by Heckler & Koch as the SA80A2 and remains in service as of 2017.  In mid-2016 a prototype A3 variant was showcased which further improved on the weapon and is reportedly being considered to extend the out of service date beyond 2025.
Answer: .455 Webley