BL 8-inch gun Mk I - VII naval gun
| BL 8-inch gun Mk I - VII naval gun | |
|---|---|
|
|
|
| General Information | |
| Military designation: | Ordnance BL 8 inch gun Mks I - VII |
| Manufacturer designation: | BL 8 inch gun |
| Manufacturer country: |
 United Kingdom
|
| Developer / Manufacturer: |
Royal Arsenal (Mk I, VI) Elswick (Mk VII) |
| Start of production: | 1884 |
| Weapon Category: | cannon |
| Technical specifications | |
| Pipe length: | Mk III: 5.105 Mk VII: 5.182 Mk IV & VI: 6.020 |
| Caliber : |
203.2 |
| Furnishing | |
| Charging principle: | Breech loader |
The BL 8 inch gun with the versions Mk I, II, III, IV and VI represent the first generation of British medium-weight breech loading ship guns . The name BL stands for breech loading ( breech loading ), 8 inch for the caliber (203.2 mm), naval gun for the originally intended use as a ship gun and Mk I – VII for the respective version (the designation of British guns at the time of construction was not uniform, guns were named according to the bullet weight, the weight of the gun or the caliber).
construction
The muzzle loaders with rifled barrel ( RML - Rifle Muzzle Loading) introduced from the mid-1860s had basically proven themselves in the Royal Navy and coastal artillery. Suitable caliber sizes had been determined in lengthy series of tests. However, progress in shipbuilding, particularly with regard to the speed and armor of steam-powered warships, required greater range and cadence as well as greater penetration. When gas-tight closures became available, the breech loader was used again. For economic reasons, however, the large numbers of black powder propellant charges should continue to be used. The cannons were therefore originally designed for the use of such propellant charges. The main distinguishing feature of the individual versions is the length of the tube. Guns with a barrel length of 25 or 30 calibers were developed. The different pipe lengths and various other modifications result in different dimensions of the individual versions.
With these guns, the grenade , the propellant charge in the form of propellant charge bags and the ignition distributor were each loaded separately.
A device to absorb the energy of the recoil was not available, so these cannons required specially constructed mounts.
The type was not further developed because the Royal Navy preferred the 9.2 inch (and later 7.5 inch) caliber from 1895. However, when the caliber of the various classes of ships was restricted with the Washington Naval Conference of 1922 , the caliber 8 inch was returned to in 1923 in order to take maximum advantage of the agreement's restrictions for heavy cruisers . At this point the Mk VIII 8-inch gun was created. In the meantime Elswick developed and manufactured a number of 8 inch guns with barrel lengths of 40 and 45 calibers for export.
Mk I and Mk II
These versions include a number of test models and prototypes , but they were never used. A small number of guns with a barrel length of 25 or 30 calibers were manufactured.
Mk III
This version is a cannon with a barrel length of 25 calibers, which was intended for the use of black powder propellants. She came on HMS Bellerophon , a battleship (Ironclad) of the Royal Navy, after its conversion in 1895 used. The bullet weight was 210 pounds (95.25 kg).
Mk IV
The Mk IV version had a tube length of 30 calibers. It was used on the Mersey-class protected cruisers (1885). Propellant charges made of cordite were used. The use of this type of propellant charge enabled longer pipe lengths and thus a higher range and penetration capacity, but also required a reinforcement of the pipe. The bullet weight did not change compared to the Mk III version.
Mk VI
The version Mk VI, tube length also 30 caliber, was used on the Indian monitors Abyssinia and Magdala after their conversion in 1892. Grenades weighing 210 pounds (95.25 kg) were also fired using cordite propellant charges.
Mk VII
The Mk VII version was a lighter version with a barrel length of 25 calibers. Lighter grenades weighing 180 pounds were used. Warships of the British colonies in Australia and the coastal fortifications there were equipped with this weapon. The immediate reason for the introduction of this weapon was the feared Russian expansion (Russian Scare) in the Pacific during the Great Game in the 1880s.
The following ships were equipped with the Mk VII version:
- HMQS Gayundah , 1884
- HMCS Protector , 1884
- HMVS Albert , 1884
- HMVS Victoria , 1884
It was also used in various coastal fortifications in the Straits Settlements in Australia and New Zealand , such as North Head . They were mounted on an articulated carriage. On the one hand, this absorbed the energy of the recoil, on the other hand, reloading was possible under armor protection. Since the feared invasion did not materialize, these cannons only fired a few sharp shots.
literature
- Additions to 1890 Manual for Victorian naval forces circa. 1895. HMVS Cerberus website
- Text Book of Gunnery, 1902. LONDON: PRINTED FOR HIS MAJESTY'S STATIONERY OFFICE, BY HARRISON AND SONS, ST. MARTIN'S LANE
Web links
- Tony DiGiulian, 8 "/ 26 (20.3 cm) Mark VII