and materially, along practical and constitutional lines. While cooperating with Sir Seyyid Ahmad Khan (sec 24.277) in over- throwing cpmmunal apathy and obscurantism as regards Western education, he deprecated his advocacy of detachment from political activity. His establishment in 1877 of the Central National Mohammedan Association, with branches throughout India, the memorial to the Government of India he promoted in 1883, and the consequent resolution of the Governor- General (Lord Dufferin) in Council in March 1885, recognizing the strength of the Moslem claims, constituted a turning-point in the history of the community, and paved the way for its fuller polit- ical organization and the reservation of Moslem scats in the legislatures under the Morley-Minto and subsequent reforms. His sustained and anxious interest in the maintenance of Moslem virility and influence throughout the world was shown by vig- orous and cogent contributions to newspapers and reviews.
AMMUNITION (see 1.864-75). The period of the World
War witnessed important developments in the design of ammuni-
tion. Although the main effort was directed towards quantity
production on a scale that no one had foreseen, and therefore to
the simplification of manufacture, yet on the other hand fresh
designs were constantly called for to meet changing tactical
conditions. Air-fighting produced the need for " tracer " and
incendiary bullets of rifle calibre and the attack of localities from
the air developed the air bomb; with the free employment of
thin armour-plate, armour-piercing bullets, radically different
from the armour-piercing shell of artillery, became necessary;
instantaneous fuzes designed to explode the shell just above
ground came into general use for wire cutting; designs of grenades
and trench-mortar bombs were brought out in profusion; and
" chemical warfare " produced a varied ammunition which in
principle was quite unlike ammunition of the customary kind.
Moreover, the needs of quantity production and in many cases the shortage of raw materials hitherto supposed to be essential to the production of projectiles and their cartricfges, themselves led to novelties of design, and lastly in the attempt to increase the efficiency of older weapons brought out of the arsenals to tide over the shortage of artillery strength, the form of pro- jectiles was revolutionized.
The subject of munitions of war collectively the organization of the munition effort in the principal countries, with its political, social and industrial ramifications, is discussed in the article MUNITIONS. The present article deals with the technical characteristics of Projectiles for Ordnance (considered from the point of view of [a] design and purpose, [b] ballistic form and [c] manufacture); Cartridges (including ignition devices) and Fuzes for Ordnance; and Ammunition for small arms and mac/tine guns. (C. F. A.)
DESIGN OF ARTILLERY PROJECTILES
The normal modern shell, whether " monobloc " or made in parts and assembled, has the general form of a cylindrical steel body, hollow to receive the filling, with the base flat and the head pointed. P'ormerly the head was usually shaped with an ogive struck with radii equal to two calibres, or diameters of the body, from centres on a line through the shoulders of the shell. The shape of the fuze was formerly not considered in relation to the contour of the shell; but when higher velocities were introduced, more attention was given to consideration of the contour of the fuze, as an clement of the head "Shape, to obviating of " yaw " and to determining efficient shapes by means of experiments and empirical results derived therefrom.
In further connexion with high velocity, long range and accuracy, the shape of the head was made more pointed, being struck with radii of several calibres, though the shape did not remain truly ogival as the centres were not on the line through the shoulders of the shell. Greater range and accuracy are aimed at by making the outer contour of the rear part of the shell tapered or " stream-lined " (in America the term " boat- tailed " is used), and this again requires the head to be still more pointed, in order to compensate for loss of range due to lessened stability, since any stream-line, however small, necessitates the ;
driving band being placed further from the base than would be the case with a cylindrical body, and the supporting surface of the shell is diminished.
Besides the true stream-lined shell, that is one with the body itself formed with a fine point and taper base, there is another class known as " false-cap " shell which was first brought into use on a larger scale in the German artillery, and in which a body of normal form, 'or even not of projectile form at all is fitted with a long thin steel hood called a " false ogive " or false cap, or ballistic cap. This makes the shell in effect a 10-15 c.r.h. shell with its centre of gravity well towards the rear. Dur- ing the World War this device, fitted to shells of older models, gave important increases of ranging power in all natures of forms in which it was applied, though the joint was not always strong enough or accurate enough to ensure the true centring of the projectile. The false cap is also found associated with the taper base in some cases.
Apart from ballistic efficiency, the design of a shell is largely determined by the stresses to which the projectile will be sub- jected on firing. The base must be of a strength sufficient to withstand the pressure of the propellant gases, and the walls of such a strength and thickness as will prevent fracture or dis- tortion under the firing and rotating stresses.
The general trend of evolution during the war may be illus- trated by comparing the characteristics of German naval shell designed before with those designed during the war. The former had thick walls and fairly small bursting charges, the head being struck with radii of less than 3 calibres and the total length being from 2-| to 35 calibres. The latter on the contrary were made with thinner walls to contain a powerful bursting charge; the shape of the rear portion made stream-lined. The head was tapered to a point and usually struck with radii of 10 calibres; sometimes the head was formed by a false cap which in later types was welded to an adapter ring screwed into the shell proper. The total length was 4 to 5 calibres.
Scale of Calibres
Note- la reality the htn of Hit
longer -pointed projut-let art fat train ogitial at drawn rtcrt
- ' 1 * \
U 1
line of centres
-2
i w"
through
- h
^
shoulders
O c*
^J *
^
CO
M
a
Illustrating terms used
b
to define shell form ' T?r
C(as a
A n
o s
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Figure I. (which is purely diagrammatical) illustrates the gen- eral significance and relations of parts as measured in calibres.
The diameter of the body of a shell is slightly less than that of the " lands " of the rifled portion of the gun-barrel, this provides a clearance or " windage " that ensures the free passage of the shell down the gun-barrel. Pressed into a groove near the base of the shell is a band termed the rotating or driving band; it is larger in diameter than the rifled portion of the gun-barrel so that, on firing, as the projectile moves, this band taking the rifling gives the neces- sary spin to the shell to keep it point foremost in flight. In several instances in the German and Austrian services, two or even three driving bands have been put on to a single shell, the better to steady the shell during its passage through the bore of a gun. 1
As a general rule the position of the band should be as near the base of the projectile as possible, it being found that the more rear- ward position of the band gives the most accurate shooting. On the other hand, a minimum distance of the band from the base is fixed by the minimum amount of material necessary for its support, for there is naturally a great strain thrown upon the shell when the band is forced into the grooves of the rifling and along their spiral, tending to tear off the base of the shell. Further, with stream-lined projectiles the band necessarily has to be placed far enough for- ward to clear the tapered base; and in Q. F. ammunition, where the projectile is carried fixed in 'the brass case, the band must be
'This is pnly^possible of course if the twist of the rifling remains uniform; with " increasing" twist only a single driving band can be used. Fig. 10 shows three different German shells with two driv- ing bands. (C. F. A.)
