Ordnance QF 3 pounder Vickers

Ordnance QF 3-pounder Vickers
On a Royal Navy monitor circa. 1918
Type	Naval gun, Anti-aircraft gun
Place of origin	United Kingdom
Service history
In service	1905-1940
Wars	World War I, World War II
Production history
Designer	Vickers
Designed	1902–03
Manufacturer	Vickers
Produced	1905-?
No. built	600
Variants	Mk I Mk II
Specifications
Weight	1,323 lb (600 kg) in total
Barrel length	8 ft 8 in (2.64 m) bore (50 calibres)
Shell	47×360mmR 3.3 lb (1.50 kg) shell.
Calibre	47 mm (1.85 in)
Breech	semi-automatic vertical block
Carriage	three-leg platform
Elevation	-5° to +12°
Traverse	360°
Rate of fire	20 rounds per minute
Muzzle velocity	2,575 ft/s (785 m/s) (HE)
Effective firing range	2,000 yd (1,829 m)(AA)
Maximum firing range	5,600 yd (5,100 m) at 12° elevation; 15,000 ft (4,600 m) (AA ceiling)
Sights	telescopic

The Ordnance QF 3-pounder Vickers (47mm / L50) was a British artillery piece first tested in Britain in 1903. It was used on Royal Navy warships. It was more powerful than and unrelated to the older QF 3-pounder Hotchkiss, with a propellant charge approximately twice as large, but it initially fired the same Lyddite and steel shells as the Hotchkiss.

Starting in 1904, the Royal Navy bought over 154 of these for use as anti-torpedo boat weapons on capital ships and to arm smaller ships. British production of these guns started in 1905 at Vickers and by the time production stopped in 1936 a total of 600 weapons had been made.

By 1911 about 193 guns of this type were in service, and they became standard equipment in the Royal Navy until 1915. In that year, service during the First World War proved these weapons to be ineffective and they were quickly removed from most of the larger ships. During the interwar years they were widely used to arm light ships and river craft. A number of them were converted into anti-aircraft guns and by 1927 at least 62 guns had been converted.