HMS Repulse

Repulse, 1939. Rangefinders, searchlight and anti-aircraft artillery stands can be seen

4 x 4’’/45 (102 mm) QF Mk XV on Mk XVIII mounts (2 x II)
4 x 4’’/45 (102 mm) QF Mk V on Mk III mounts (4 x I)
2 x Hotchkiss 3-pdr (1.85’’/40. 47 mm) QF Mk I on Mk I mounts (saluting guns)
16 x 2-pdr (40 mm/39) Mk VII pom-poms on Mk VI mounts (2 x VIII)
8 x 0.50’’/62 (12.7 mm) Mk III on Mk II mounts (2 x IV)
8 x fixed above water 21’’ (533 mm) Mk IV torpedo tubes (4 x II)

Armament (1939)
6 x 15’’/42 (381 mm) Mk I installed in Mk I* turrets (3 x II)
12 x 4’’/42 (102 mm) BL Mk IX on Mk I mounts (4 x III)
6 x 4’’/45 (102 mm) QF Mk V on Mk III mounts (6 x I)
16 x 2-pdr (40 mm/39) Mk VII pom-poms on Mk VI mounts (2 x VIII)
16 x 0.50’’/62 (12.7 mm) Mk III on Mk II mounts (4 x IV)
8 x fixed above water 21’’ (533 mm) Mk IV torpedo tubes (4 x II)

Armament (1941)
6 x 15’’/42 (381 mm) Mk I installed in Mk I* turrets (3 x II)
9 x 4’’/42 (102 mm) BL Mk IX on Mk I mounts (3 x III)
6 x 4’’/45 (102 mm) QF Mk V on Mk III mounts (6 x I)
24 x 2-pdr (40 mm/39) Mk VII pom-poms on Mk VI mounts (3 x VIII)
16 x 0,50’’/62 (12,7 mm) Mk III on Mk II mounts (4 x IV)
8 x 20 mm/70 Oerlikon Mk II (6 x I)
8 x fixed above water 21’’ (533 mm) Mk IV torpedo tubes (4 x II)

Armament
The Renown class ships carried 15”/42 (381 mm) main guns mounted in twin Mk I* turrets. The gun was a very long-lived design and it was carried by as many as 22 Royal Navy vessels. The weapon was designed by Vickers-Armstrong back in 1912 and the first examples entered service in 1915. In total 186 guns of that type were manufactured between 1912 and 1915 along with 58 turrets. The main gun battery on HMS Repulse was mounted in two fore turrets (A and B) arranged in a superfiring position. Turret Y was located aft of the aft superstructure. Mk I* turrets were upgraded versions of the Mk I design and featured improved projectile and powder charge feed mechanism. Externally the Mk I* turret differed from the Mk I in that the former had a rounded front armor plate, while the latter featured a multi-angular plate.
By the 1930s the 15”/42 gun was an outdated design, so the British decided to update the existing examples rather then embark on a costly gun replacement program. Under the upgrade program the gun’s poor effective range was to be raised by increasing the maximum elevation angle from 20 to 30 degrees and the use of new, more streamlined projectiles. The changes were introduced on HMS Renown during the ship’s modernization in 1936 – 1939. Her sister ship, however, would never undergo the weapons modernization program (partially, perhaps, because she was sunk in the early stages of the war).

15”/42 Mk I main guns mounted in Mk I* turrets
Caliber    15’’ (381 mm)
gun weight    101 605 kg
Gun length oa    16.52 m
Bore length    16.002 m (42 calibers)
Grooves    76
Chamber volume    502.3 dm3
Breech mechanism    Welin type
Rate of fire    around 2 rounds per minute
Ammunition    World War I APC Mk Ia – 871 kg (27.4 kg Lyddite bursting charge)
HE – 871 kg (98.2 kg bursting charge)
World War II
APC Mk XIIa – 879 kg (22 kg Shellite bursting charge)
APC Mk XIIIa – 879 kg (22 kg Shellite bursting charge)
Propellant charge    World War I 194 kg MD45
World War II
196 kg SC280
Barrel life    up to 350 rounds
Ammunition stowage    120 rounds per gun
Range    21 702 m
Turret weight    770 t
Elevation    -5° to +20°
Train    -150° to +150°

When she first entered service Repulse’s medium battery consisted of 17 relatively light caliber 4” guns (BL Mk IX). The weapons were installed in five tripple Mk I shielded mounts (two on each side of the forward stack, three on the aft superstructure along the ship’s centerline) and in two single mounts (each side of turret B on the shelter deck). The guns proved to be a big dissapointment. Training and elevating the weapons was a highly laborious exercise, not to mention that each triple set required a large crew (28 – 32 men). Not surprisingly the guns were gradually phased out from use aboard the ship: during the 1918 – 1921 refit the single-mounted cannons were removed, followed by triple installations that disappeared from in front of the mainmast during the 1933 – 1936 modernization and another triple mount that was removed in 1940. In 1941 only nine guns of that type still remained on Repulse’s deck.
1924 saw the installation of much improved and more modern 4” guns – 4”/45 QF Mk V single-mounted on unshielded Mk III mounts. Two such installations were placed on each side of the aft stack, while two more were added to the forecastle deck in the fore stack area. At the same time two sets of very similar 4”/45 (102 cm) QF Mk XV guns twin-mounted on Mk XVIII mounts were installed on the aft superstructure, each side of the mainmast. Mk XVIII mounts were experimental BD (between decks) type units. The guns’ rate of fire proved to be inadequate and during the 1939 refit they were replaced with 4”/45 QF Mk V models, which increased the total number of these weapons to six.

4”/45 QF Mk V guns on Mk III mounts
Caliber    4’’ (102 mm)
Gun weight    2.138 t (without breech mechanism)