Cordite

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.

Cordite Mark I

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.

Cordite M.D.

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

On 23 December, 1908, the Admiralty ordered that the outfits of cordite, other than first use cordite, in H.M. ships was to be reorganised. Cordite manufactured by Waltham Abbey, Cotton Powder Co., and New Explosives Co., was to be sorted into lots, without restrictions as to date, as was cordite manufactured by other makes since 1907. All Cordite M.D., whether B.L. or Q.F., manufactured before 1908 by Nobel, Chilworth Powder Co., Curtiss and Harvey, British Explosives Syndicate, Kynoch, and National Explosives Co., was to be landed and tested.

The results of the heat test of the landed cordite was:

	1902.	1903.	1904.	1905.	1906.	1907.
Manufacturer.	% found doubtful.	% found doubtful.	% found doubtful.	% found doubtful.	% found doubtful.	% found doubtful.
Cotton Powder Co. (C.)	—	—	2.5	—	—	—
Waltham Abbey (W.A.)	3.03	1.35	1.85	—	—	—
New Explosives Co. (E.)	—	50.0*	—	—	—	—
Chilworth Powder Co. (B.)	50.0*	—	3.84	—	—	—
British Explosives Co. (S.)	—	—	33.3	—	—	—
Curtiss & Harvey (H.)	—	33.33	26.09	10.0	11.40	—
National Explosives Co. (N.)	—	30.77	28.39	2.44	—	—
Nobel's Explosives Co. (D.)	14.28	39.13	37.03	32.83	13.04	—
Kynoch, Ltd (K.)	—	70.25	19.35	7.14	—	—

Though somewhat less persistent in the air than the brown propellant powder it replaced, Cordite produced large volumes of dense smoke when fired – perhaps slightly more so than Mark I. A report in the Mediterranean on long range firing in 1903 placed special attention to the problems arising from this obscuration.

Russell reported that it hampered the use of a rangefinder atop her chart house, as it could not see anything when firing broadsides. Six other battleships agreed with her assessment that the gun layers faced "serious" interference from the smoke, particularly when the ship was stopped or faced little relative wind, as with a following wind. It was well noted that the bearing of firing and the effect of relative wind were important factors in the degree of interference caused. Particular mention was made of difficulty in spotting from the casemates; 6-in gun "X 3" in Russell was idle for two full minutes on account of being totally obscured.

Vice-President of the Ordnance Committee, Rear-Admiral Alfred Parr wrote a paper in response to the report drawing on his experiences in command of Prince George, in which he asked whether the problems were so bad as suggested or if the exercise had been carried out in relative wind conditions of the worst possible kind. By late November, 1903, the adverse results were deemed insufficiently grave compared to the ballistic benefits expected of the new composition, and M.D. adoption proceeded apace.

Cordite S.C.

Cordite development continued after the First World War, with Cordite S.C. being introduced to the Fleet in 1927. A flashless cordite N.F. (formerly N.F.Q.) was also used by the Navy during the Second World War. There are those who insist that some sort of connection can be made between the British use of Cordite in the First World War to the fact that over twenty-five years later the United States Navy, with a history of using single-base propellants, was unsatisfied using Cordite N., a Canadian-produced variant of Cordite N.F. for army use. This is of course fatuous.

Manufacture

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.

Composition of Cordite Mark I
Ingredient.	Percentage.
Nitroglycerin	58%
Nitrocellulose (Nitrogen)	37% (13.1%)
Petroleum Jelly	5%

Composition of Cordite M.D.
Ingredient.	Percentage.
Nitroglycerin	30%
Nitrocellulose (Nitrogen)	65% (Average 13.1%)
Petroleum Jelly	5%

See Also

• Cordite Cartridge
• A Direct Train of Cordite, an examination of Royal Navy efforts to diagnose magazine explosions at the Battle of Jutland