On the heels of the success of the pistol and shotgun markets, Webley decide to enter the air gun market in the early 1900's when the UK Firearms Act of 1920 required people to obtain a firearms certificate to purchase or possess a firearm. After several years of development, Webley released their first air pistol, the Mark I in 1924.
Webley released their first air rifle (Mark I Air Rifle) two years later in 1926. The Webley Mark I air rifle set the standard for such guns. A break-barrel, spring rifle, it is today very much a collectors piece. The follow-up model, the MKII Service (1929), became known as the Service as it was used to train Army recruits. Today, a complete gun in its original case could fetch as much as $3,000.