All officers in the British Army carried pistols during the First World War. They were also issued to the military police, aircrew and operating personnel of tanks and armoured cars. Of those available, the British Army tended to prefer the Webley MkIV. Originally designed in 1887, but improved during the early stages of the war, the Webley was a strong heavy-calibre weapon. It has been estimated that over 300,000 Webley pistols were distributed to British officers during the war.