ss consists in mounting
ten of the metal drums on a reeling machine similar to those used for
yarns, and winding the ten cords on to one drum. This operation is known
as "ten-stranding." Furthermore, six "ten-stranded" reels are afterwards
wound upon one, and the "sixty-stranded" reel is then ready to be sent
away, This is done in order to obtain a uniform blending of the material.
With cordite of a larger diameter, the cord is cut into lengths of 12
inches. Every lot of cordite from each manufacturer has a consecutive
number, numbers representing the size and one or more initial letters to
identify the manufacturer. These regulations do not apply to the Royal
Gunpowder Factory, Waltham Abbey. The 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. Cordite is
practically smokeless. On explosion a very thin vapour is produced, which
is dissipated rapidly. This smokelessness can be understood from the fact
that the products of combustion are nearly all non-condensible gases, and
contain no solid products of combustion which would cause smoke. For the
same muzzle velocity a smaller charge of cordite than gunpowder is
required owing to the greater amount of gas produced. Cordite is very slow
in burning compared to gunpowder. For firing blank cartridges cordite
chips containing no vaseline is used. The rate at which cordite explodes
depends in a measure upon the diameter of the cords, and the pressure
developed upon its mechanical state. The sizes of cordite used are given
by Colonel Barker, R.A., as follows:--
For the .303 rifle .0375 inch diameter.
" 12 Pr. B.L. gun .05 "
" " .075 "
" 4.7-inch Q.F. gun .100 "
" 6-inch Q.F. gun .300 "
" heavy guns .40 to .50 "
For rifles the cordite is used in bundles of sixty strands, in field-guns
in lengths of 11 to 12 inches, and the thicker cordite is cut up into
14-inch lengths. Colonel Barker says that the effect of heat upon cordite
is not greater as regards its shooting qualities than upon black powder,
and in speaking of the effect that cordite has upon the guns in which it is
used (R.A. Inst.) said that they had at Waltham Abbey a 4.7-inch Q.F. gun
that had fired
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