Cordite

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Cordite was a solid propellant used in various grades by the Royal Navy from 1889, replacing brown powder propellant. It has received a somewhat poor reputation, being widely held responsible for the loss of a number of warships owing to catastrophic magazine explosions.

History

Quoted herewith is a description of cordite manufacture from 1902:

Nitro-glycerine, in the proper proportion, is poured on to dry gun-cotton, [nitrocellulose] to which no alkali has been added, and the two are mixed by hand.

In this condition it is known as cordite paste.

The paste is placed in an incorporating machine, some acetone being first poured in. The machine is started, and the remainder of the acetone is added. After kneading for hours, the mineral jelly is added, and the kneading continued for a further period of 3½ hours. The mixture, in the condition of a plastic dough, is then placed in cylindrical moulds. The mould is inserted in a press, and the cordite is forced through a die with one or more holes. The cordite comes through the die in long cords, and is cut to length and placed in trays or wound on reels. The cordite is then stoved, at a temperature of about 100° F., from 3 to 14 days, the time varying with the size. This operation drives off the acetone or any moisture, the cordite becomes tougher, and its diameter decreases. Cordite is then blended.

All lots of cordite from each manufacturer have consecutive numbers, irrespective of size, and one or more initial letters to identify the manufacturer, except Waltham Abbey cordite, which has only the lot number. Finished cordite resembles a cord of gutta percha, and its colour varies from light to dark brown. It should not look black or shrivelled, and should always possess sufficient elasticity to return to its original form after slight bending.[1]

Composition of Cordite Mark I[2]
Ingredient. Percentage.
Nitroglycerin 58%
Nitrocellulose
(Nitrogen)
37%
(13.1%)
Petroleum Jelly 5%
Composition of Cordite MD[3]
Ingredient. Percentage.
Nitroglycerin 30%
Nitrocellulose
(Nitrogen)
65%
(Average 13.1%)
Petroleum Jelly 5%

Cordite Mark I began to be manufactured in 1889. It was first distributed to the Fleet in 1893 as propellant for 6-inch, 4.7-inch, 6-pdr, and 3-pdr Q.F. guns.[4]

With Cordite MD, first delivered in 1901, the calories per gram on burning (water as liquid) were reduced from 1,270 to 1,020.[5]

Cordite development continued after the First World War, with Cordite SC being introduced to the Fleet in 1927.[6] A flashless cordite NF (formerly NFQ) was also used by the Navy during the Second World War.[7] There are those who insist that some sort of connection can be made between the British use of Cordite in the First World War[8] to the fact that over twenty-five years later the United States Navy, with a history of using single-base propellants, was unsatisfied after trialling Cordite N, a Canadian-produced variant of Cordite NF for army use.[9]

See Also

Footnotes

  1. Treatise on Ammunition. pp. 20-21.
  2. Campbell (1978). p. 139.
  3. Campbell (1978). p. 139.
  4. Campbell (1978). p. 139.
  5. Campbell (1978). p. 139.
  6. Campbell (1978). p. 140.
  7. Campbell (1985). p. 5.
  8. Wikipedia Article on the Battle of Jutland.
  9. Campbell (1985). p. 104.

Bibliography