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During the British attack on the French Fleet at Dakar in September 1940, Richelieu returned fire, but the two starboard guns of her Turret II both failed at the first salvo. The inner gun burst and the outer gun bulged with the rifling gashed for 8 meters (26 feet). The cause was eventually traced to a defective shell design. AP shells had 4 cavities which could contain mustard gas or some other war gas. These holes were protected by a base cap, but this broke under the pressure generated when the guns fired. Splinters from the broken base cap smashed through the gas cavities and into the explosive charge which then detonated. After this incident, a new base cap was produced and the gas cavities were filled in with cement. These failures may have been due to the propellant, which was reportedly that used for the 33 cm (13") Model 1931 guns used on the Dunkerque class. Jean Bart had only her Turret I guns installed when France fell in May 1940. The French tried to load the four guns intended for her Turret II onto a cargo ship at St. Nazaire but the crane failed after only two guns had been transferred. The remaining two guns were then mutilated on the dock and the cargo ship sailed for North Africa, but she was sunk by German aircraft shortly after leaving harbor. During Richelieu's refit in the USA in 1943, three of her ruined guns were replaced by guns removed from Jean Bart's Turret I. It is apparently untrue that Richelieu's guns were bored out to 15.0" (38.1 cm) during this time, as French records indicate that they remained at 380 mm (14.96"). Sometime after this refit, new AP and HE shells designed to meet French specifications were specially built for her by the Crucible Steel Company of America. The uncompleted Clemenceau was destroyed on the slip but the eight guns intended for her were captured by the Germans and taken to Norway. At least three of these were planned for a coastal battery at Vardaasen, but it does not appear that they were ever made operational. After the war, all eight guns were returned to France where they were then used to arm Jean Bart. Richelieu had delay coils for the center guns of each turret fitted in 1947-1948 when a tighter dispersion pattern was desired in order to take the maximum advantage of radar fire control. During tests at Mers el-Kébir in May 1948, the measured average dispersion at 26,500 meters (29,000 yards) was 525 meters (575 yards) without the firing delay and 300 meters (330 yards) with a 0.060 second firing delay (at this time the guns had all fired more than 200 shells without refit). These weapons were mounted in quad turrets, which were really more of a dual-twin arrangement. The quad mounting was chosen as a result of weight considerations, as it meant less turret and protective belt armor was required, an important consideration for ships designed under Treaty limitations. However, this configuration did mean that a single hit could destroy half of the main armament. The individual guns were sleeved, although some descriptions imply that the relative motion of the guns in each pair was limited. The French were apparently unhappy with the all-forward arrangement, as the design for the last ship in the class, Gascogne, returned to the more traditional fore-aft arrangement. The construction was apparently loose liner, A tube, screwed on breech bush, ten hoops, three tubes to the muzzle ending in a muzzle bush and a breech ring bush. The outer layer comprised a jacket in two layers. This complex assembly is a curious mix of modern and traditional French methods. The Welin breech mechanism opened upwards automatically as the the gun ran out after firing. It was hydro-pneumatically powered and balanced by counterweights. An automatic lock with ten electric tubes for firing was fitted to the breech mechanism. At least one gun from Richelieu is still in existence and is on display at the military harbor of Brest, near Recouvrance Bridge. |
Battleship Richelieu in the 1950s
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Richelieu entering New York Harbor in 1943
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380 mm gun for Jean Bart in February 1948
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The gun pictured above being installed
in Turret I on Jean Bart in February 1948
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| Designation | 380 mm/45 (14.96") Model 1935 |
| Ship Class Used On | Richelieu, Gascogne and Alsace classes |
| Date Of Design | 1935 |
| Date In Service | 1941 |
| Gun Weight | 207,200 lbs. (94,130 kg) |
| Gun Length oa | 704.0 in (17.882 m) |
| Bore Length | 679.4 in (17.257 m) |
| Rifling Length | 557.4 in (14.157 m) |
| Number Of Grooves | (80) 0.146 in deep x 0.350 in (3.7 mm x 8.9 mm) |
| Lands | 0.236 in (6.0 mm) |
| Twist | Uniform RH 1 in 25.57 |
| Chamber Volume | 27,863 in3 (456.6 dm3) |
| Rate Of Fire
(see Notes) |
1.2 - 2.2 rounds per minute |
| Notes:
1) The rate of fire was hampered by the slow rate in which the hoists could deliver projectiles. Reportedly, the pre-war average rate of fire for Richelieu was 1.33 rounds per minute. When Jean Bart was completed post-war, she could then achieve a rate of fire of nearly two rounds per minute. 2) A spanning tray to protect the breech threads ran in and out automatically. Complete ramming time was 13.5 seconds. The breeches were operated hydro-pneumatically and opened upwards automatically during the runout cycle. Breech opening and closing times are both given as 3.5 seconds. |
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| Type | Bag |
| Projectile Types and Weights | AP - 1,949 lbs. (884 kg)
HE - 1,949 lbs. (884 kg) |
| Bursting Charge | AP - 48.3 lbs. (21.9 kg) TNT (French)
AP - 48.3 lbs. (21.9 kg) Explosive D (USA) HE - N/A |
| Projectile Length | AP - 74.8 in (190 cm)
HE - 74.8 in (190 cm) |
| Propellant Charge
(see Notes 3 and 4) |
635 lbs. (288 kg) SD21 |
| Muzzle Velocity | Original: 2,723 fps (830 mps)
USA Charge: 2,625 fps (800 mps) Range Tables: 2,575 fps (785 mps) |
| Working Pressure | 20.3 tons/in2 (3,200 kg/cm2) |
| Approximate Barrel Life | 200 rounds |
| Ammunition stowage per gun | 104 rounds |
| Notes:
1) Apparently only AP rounds were developed prior to 1940. HE shells may have been first produced for these guns by Crucible Steel Company of America. Actual designation for dye-filled APC "K" shells was: 38 cm Obus de Perforation (RC) K Modele 1936. 2) The propellant charge was in quarters, making them unusually heavy. These were rammed two at a time, with inertia holding the first two bags in place while the last two were rammed. 3) USA multi-tube charges were supplied after the Richelieu's New York refit, but these were disliked by the French because they had a tendency to warp and break during handling. 4) Modified SD19 powder bags (originally designed for the Dunkerque class) were also used during 1944-1945. These gave a slightly reduced muzzle velocity of 2,690 fps (820 mps). 5) Both AP and HE shells had dye bags ("K" shell). Richelieu was assigned yellow and Jean Bart orange. 6) The AP cap weight was 185 lbs. (84 kg). 7) The AP burster was composed of 80% melinite and 20% dinitronaphtaline. 8) The US designed-and-manufactured APC
projectiles were externally identical to the French design and weighed
the same, with the exact same cavity shape and percentage. The base
fuze was the US Mark 21 BDF. The filler was Explosive "D", not TNT.
The base plug was the standard US Navy design, as was its threaded sides
and other details. The biggest visual difference in the blueprints
between the US and original French APC projectiles was that the AP cap
and nose shape was that of the US Navy 14" Mark 16 Mod 8 AP projectile:
Oval nose under the cap and a flat-tipped-cone-faced, moderately thick,
moderately hard (circa 555 Brinell
9) The original French projectiles had pointed, hardened AP caps contoured to the bluntly-pointed nose under the cap, getting gradually thicker from just above the bourrelet to about the same level as the tip of the nose (33 cm gun design) or somewhat higher (last 38 cm gun design), at which level they abruptly became much blunter, though still thickening to a blunt point in the center. The lower edge of the cap was softened and was forced into a shallow groove ring cut into the projectile's lower nose all around, not in the spaced dimples of the US design. The long French windscreen design was reinforced to hold the K spotting dye-bag charge and had a much wider attachment threaded area to the AP cap's upper side to more firmly hold the windscreen in place. Also, this reinforcement had a wide flat "floor" braced against the upper face of the AP cap, so that when the windscreen's K filler explosion removed most of the windscreen, this flat area would remain, allowing the shell to dive underwater exactly like a Japanese Type 91 diving shell with minimum drag or projectile path distortion. |
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| Elevation |
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| 4.4 degrees |
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| 7.4 degrees |
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| 10.9 degrees |
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| 14.9 degrees |
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| 19.8 degrees |
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| 25.5 degrees |
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| 35.0 degrees |
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| Note: The values in the table above are for the original French charge. At the 2,575 fps (785 mps) muzzle velocity used in some range tables, the maximum range was 41,065 yards (37,550 m). The maximum range for the USA supplied charge and projectiles is not available, but for the muzzle velocity given I would estimate that it would have been approximately 43,000 yards (39,300 m). | |||
| Range |
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| 0 yards (0 m) |
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| 24,060 yards (22,000 m) |
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| 29,528 yards (27,000 m) |
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| 38,280 yards (35,000 m) |
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| 41,560 yards (38,000 m) |
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| Note: This data is based upon the USN Empirical Armor Penetration Formula and is a combination from information given in "Battleships: Allied Battleships in World War II" and "Richelieu." However, the former says it is for a muzzle velocity of 2,575 fps (785 mps) while the latter says it is for a muzzle velocity of 2,690 fps (820 mps). Both books agree as to the armor penetration values. | |||
| Designation | Quad Mount
Richelieu (2), Gascogne (2) and Alsace (3): Model 1935 |
| Weight | 2,274 tons (2,476 mt) |
| Elevation | -5 / +35 degrees |
| Rate of Elevation | 5.5 degrees per second |
| Train
(see Note 4) |
Richelieu
Turret I: -150 / +150 degrees Turret II: -156 / +156 degrees Gascogne
Alsace
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| Rate of Train | 5 degrees per second |
| Gun Recoil | 52.2 in (132.5 cm) |
| Loading Angle | Any |
| Notes:
1) These turrets were equipped with a unique "semi-flexible" chain rammer carried on an extension from each cradle which permitted loading at any angle and thus a theoretical high rate of fire. The shells were "vigorously rammed" so that they would be held in place at high elevations by their own driving bands. However, I have to question if shells sliding back out of the breech when operated at high elevations was a problem, as loading was typically performed at about +15 degrees of elevation. 2) Both training and elevation were electro-hydraulic with RPC. 3) The gunhouse was divided by a 4.5 cm (1.8") bulkhead. 4) Gascogne was a modified design with a fore and aft turret rather than the all-forward design of her half-sisters. For that reason, her main-battery arcs were limited to allow the placement of more AA guns in areas free from blast effects. Alsace was the proposed lead ship of a new class of battleships with a standard displacement of around 45,000 tons (45,700 mt). None of these battleships were laid down at the time of the surrender. 5) Each turret had two sets of shell rooms and powder magazines, each pair on the same deck at opposite ends of the barbette. The pairs were stacked one above the other on two decks with each pair feeding two guns in a half turret. There were two dredger hoists to a handling room below the turret with an upper hoist going to each gun. The upper hoist was a three-level cage, with the shell riding in the lower level and two powder bags on each of the upper levels. 6) The gun axis in each pair were 76.8 in (195 cm) apart while the two inner guns were 116.1 in (295 cm) apart. |
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