The Webley & Scott No.1 Mk.1 flare gun was introduced during WW1 and was used for firing signals and illuminating cartridges. The attached shoulder stock and long barrel are original features of the gun. The first guns were delivered in 1915.
After WW1, Federal Laboratories Inc., Pittsburg, Pennsylvania, USA., purchased a quantity of surplus Webley & Scott No.1 Mk.1 flare guns and a quantity of surplus signalling cartridges.
The cartridges had the pyrotechnic composition removed, and this was replaced with a CN tear gas composition.
The Webley & Scott No.1 Mk.1 flare guns purchased by Federal Laboratories Inc., had the metalwork chromium plated and the stock stamped ‘FEDERAL LABORATORIES INC. PITTSBURG. PENNA’. Some sources say the Webley & Scott markings were removed. They might have been polished off as part of the preparation process for the chromium plating.
These refinished Webley & Scott No.1 Mk.1 flare guns were then sold by Federal Laboratories Inc. as the ‘FEDERAL 1 ½” CAL. GAS RIOT GUN’.
(In the 1930’s Federal introduced their own design of riot gun that replaced the refinished Webley & Scotts)
In 1969 when the Royal Ulster Constabulary fired tear gas at demonstrators in what became known as the ‘battle of the Bogside’, the RUC were equipped with Webley & Scott No.1 Mk.1 flare guns.
The British Army also used Webley & Scott No.1 Mk.1 flare guns (as well as No.4 Mk.1* flare pistols) to fire CS and rubber bullets in the early years of the troubles in Northern Ireland.
In the Star Wars movies, the Webley & Scott No.1 Mk.1 flare gun was used as the base gun upon which Boba Fett’s blaster was built.
(Photos through Google images showing copyright details where known. The Federal gun is from a thread on machinegunboards)