203 mm modèle 1924
| 203 mm modèle 1924 | |
|---|---|
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| General Information | |
| Military designation: | 203 mm modèle 1924 |
| Manufacturer country: |
 France
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| Weapon Category: | Ship gun |
| Technical specifications | |
| Overall length: | 10.5 m |
| Caliber : |
203 mm |
| Caliber length : | 50 |
| Number of trains : | 60, 1.9 mm x 7.5 mm |
| Twist : | right-handed, 1 turn on 25.59 caliber lengths |
| Weight ready for use: | 20,716 kg |
The 203 mm modèle 1924 was a French naval gun from before and during World War II . It served as the main armament on all French heavy cruisers and the French U-cruiser Surcouf .
description
The gun consisted of a barrel on which a jacket tube and a lock ring were shrunk . The gun had a Welin screw lock system that opened upwards. The gun barrel was subjected to an autofrettage during manufacture . The caliber length was L / 50, which corresponds to a barrel length of 10.15 m.
It fired separate ammunition, consisting of a grenade and a propellant charge in two cartridge bags . Different types of shell were available (see table below).
Ammunition and performance
Several types of armor-piercing shells and HE shells were developed for the gun. The French Navy designated armor-piercing grenades with OPf ("obus de perforation"), HE shells with OEA ("obus explosif en acier", literally "high-explosive grenade made of steel").
| designation | Type | Weight. | Muzzle velocity | Range |
|---|---|---|---|---|
| OPf modèle 1927 | armor piercing | 123.1 kg | 850 m / s | 28.0 km at 30 ° elevation 31.4 km at 45 ° elevation |
| OEA modèle 1927 | HE grenade | 123.8 kg | 850 m / s | 30.0 km at 45 ° elevation |
| OPf model 19 ?? | armor piercing | 119.1 kg | 850 m / s | |
| OEA modèle 19 ?? | HE grenade | 119.7 kg | 850 m / s | |
| OPf modèle 1936 | armor piercing | 134 kg | 820 m / s | 30.0 km at 45 ° elevation |
The propellant charge was of the type BM 13 and weighed 53 kg. The armor-piercing grenade OPf modèle 1936 was fired with a lower load of 47 kg for a reduced muzzle velocity.
The explosive charge of the grenades was 8.1 kg of Mélinite - an explosive based on picric acid - in the armor-piercing grenade OPf modèle 1927 . About 8.3 kg of Mélinite were used in the HE shells.
The armor-piercing grenade OPf modèle 1936 received a colored bag in 1939, which colored the water columns in the event of missed shots and thus allowed an assignment to the firing ship. The colors assigned to the ships were: Duquesne red, Tourville yellow and Suffren green.
use
Heavy cruisers
The heavy cruisers of the Duquesne class and the Suffren class carried their weapons in the lightly protected twin towers of the 1924 model. The single ship Algérie carried the 1931 twin tower, which was much more heavily armored and therefore differed slightly from the previous model.
In the 1924 and 1931 model turrets, the guns were stored in separate barrel cradles , but could be coupled together. The guns had an elevation range of −5 ° to 45 ° and could be loaded at elevation angles of −5 ° to 10 °. The lateral straightening range was around ± 150 ° and was limited by the superstructures of the ships.
Each gun had an electric motor with 30 HP for the vertical direction. A 22.5 HP electric motor with hydraulic power transmission was available to swivel the towers. The guns could be aimed at about 10 ° per second in height, the turrets could be pivoted at 6 ° per second. In the mid-thirties, the towers were retrofitted with a remote control for side straightening.
The turrets were connected to the magazines below via two-stage ammunition lifts. Two conveyors transported grenades and propellant charges into the reloading chamber under the tower. There they were transferred to two elevators that ended in the tower on the outside of the guns. The shells were transferred to a loading cradle, which was locked to the gun for loading. The grenade was then loaded into a spring-driven rammer that had been cocked by the recoil of the previous shot. The cartridge pouches were loaded manually.
The turrets were designed for a rate of fire of 5 to 6 rounds per minute and gun, but in practice only achieved 3 to 4 rounds or 4 to 5 rounds per minute, depending on the source.
Surcouf
The tower model 1927 was specially developed for the Surcouf . This was completely watertight and pressure-tight. He could already be manned under water to enable a quick fire opening after surfacing. This was possible within two and a half minutes of surfacing. The turret reached a rate of fire of 3 rounds per minute and gun. The elevation range of -5 ° to 30 ° was somewhat lower than that of the towers of the heavy cruisers, the loading position was the same with -5 ° to 10 °. The lateral straightening range was severely restricted to ± 11 °.
Individual evidence
- ↑ a b c d e f g h i j k l John Jordan, Jean Moulin: French Cruisers 1922–1956. Seaforth Publishing, Barnsley 2013, ISBN 978-1-84832-133-5 , pp. 48f.
- ^ John Jordan, Jean Moulin: French Cruisers 1922-1956. Seaforth Publishing, Barnsley 2013, ISBN 978-1-84832-133-5 , pp. 114f.
- ^ John Jordan: Warships after Washington. Seaforth Publishing, Barnsley 2011, ISBN 978-1-84832-117-5 , p. 251.