7.5"/45 (19 cm) Mark I
A Vickers design. Suffered from "steel choke" and many guns used cannelured rings as a corrective measure.
Constructed of 'A' tube, inner 'A' tube, wire winding nearly full length, 'B' tube and jacket. There was a shrunk-on collar at the rear end of the 'A' tube and this and a screwed ring at the rear, secured the 'B' tube and jacket longitudinally. Used a Welin breech mechanism. Mark I* had a breech ring to which the breech mechanism was attached, the assembly shrunk over the rear end of the 'A' tube and then screwed to the jacket. Mark I** had a thicker 'A' tube end and a larger diameter breech ring. These differences apparently replaced the breech ring. A total of 33 guns were made, including three prototypes. Of these, 13 are known to have been Mark I* and four were either Mark I* or Mark II**.
|Designation||7.5"/45 (19 cm) Mark I|
|Ship Class Used On||Devonshire class and M.26|
|Date Of Design||about 1903|
|Date In Service||1905|
|Gun Weight||13.76 tons (14.0 mt)|
|Gun Length oa||349.2 in (8.870 m)|
|Bore Length||about 375.0 in (9.525 m)|
|Rate Of Fire||4 -5 rounds per minute|
|Projectile Types and Weights||AP: 200 lbs. (90.7 kg)
Common: 200 lbs. (90.7 kg)
CPC: 200 lbs. (90.7 kg)
HE: 200 lbs. (90.7 kg)
|Muzzle Velocity||2,765 fps (843 mps)|
|Approximate Barrel Life||N/A|
|Ammunition stowage per gun||N/A|
Projectiles were 2crh.
|15 degrees||14,008 yards (12,810 m)|
Taken from range tables, but "Warship Volume VII" says that these were probably about 200 yards (180 m) too long.
|Range||Vertical KC Plate|
|3,000 yards (2,740 m)||4.5 in (11.4 cm)|
Data from "The Grand Fleet: Warship Design and Development 1906-1922" for an angle of obliquity of 30 degrees and a striking velocity of 1,640 fps (500 mps). Projectiles were salt-filled (blind).
|Elevation||about -5 / +15 degrees|
|Elevation Rate||Manual operation, only|
|Train||Bow and Stern mounts: about +150 / -150 degrees
Wing mounts: about +30 / +150 degrees
- The Vickers Photographic Archive
- See photographs 6470 and 6796
- "Warrior to Dreadnought: Warship Development 1860-1905" and "The Grand Fleet: Warship Design and Development 1906-1922" both by D.K. Brown
- "British Naval Guns 1880-1945 No 9" article by John Campbell in "Warship Volume VII"
- "World Warships in Review 1860-1906" by John Leather
Special help by Daniel Muir
- 07 January 2007
- 11 February 2012
- Updated to latest template
- 01 December 2015
- Changed Vickers Photographic Archive links to point at Wayback Archive