Nitro-Explosives: A Practical Treatise

eneral-Cordite-Axite-

G. Powder-Indurite-V

oppal Powders-Amberit

id Powder

o-lignine; or else contain, in addition to the above, nitro-glycerine, with very often some such substance as camphor, which is used to reduce the sensitiveness of the explosive. Other nitro bodies that are used, or have been proposed, are nitro-starch, nitro

of the better known purely military powders are not suited for use in sporting guns, nearly all the manufacturers of sporting powders also manufacture

ich contains nitro- glycerine and nitro-cotton); and among the general powders, two varieties of which are manufactured eith

kneading continued for a further three and a half hours. The kneading machine (Fig. 29) consists of a trough, composed of two halves of a cylinder, in each of which is a shaft which carries a revolving blade. These blades revolve in opposite directions, and one makes about half the number of revolutions of the other. As the blades very nearly touch the bottom of the trough, any material brought into the machine is divided into two parts, kneaded against the bottom, then pushed along the blade, turned over, and completely mixed. During kneading the acetone gradually penetrates the mixture, and dissolves both the nitro-cellulose and nitro-glycerine, and a uniform dough is obtained which gradually assumes a buff colour. During kneading the mass becomes heated, and therefore cold water is passed through the jacket of the machine to prevent heating the mixture above the normal temperature, and consequent evaporation of the acetone. The top of the machine is closed in with a glass door, in order to prevent as far as possible the evaporation of the solvent. When the various ingredients are formed into a homogeneous mass, the mixture is taken to the press house, where in the form of a plastic mass it is placed in cylindrical moulds. The mould is inserted in a specially designed press, and the cordite paste forced through a die with one or more holes. The paste is pressed out by hydraulic pressure, and the long cord is wound on a metal drum (Fig. 38), or cut into lengths; in either case the cordite is now sent to the drying houses, and dried at a temperature of about 100° F. from three to fourteen days, the time varying with the size. This operation drives off the acetone, and any moisture the cordite may still contain, and its diameter decreases somewhat. In case of the fine

.L. gun .05 " " " .075 " " 4.7-inch Q.F. gun .100

r 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 40 rou

r cent. of soluble gun-cotton, and a nitrogen c

Scale, 1 inch = 1 foo

: FIG. 38.-"T

,146 foot seconds, and the muzzle energy 1,437 foot tons. A gramme of cordite generated 700 c.c. of permanent gases at 0° C. and 760 mm. pressure. The quantity of heat developed was 1,260 gramme units. In the case of cordite, as also with ballistite, a considerable quantity of aqueous vapour has to be added to the permanent gases formed. A similar trial, in which

c. Roy. Soc., vo

on. A number of wooden cases, containing 500 to 600 lbs. each of cordite, were placed upon a large bonfire of wood, and burned for over a quarter of an hour without explosion. At Woolwich in 1892

ms it is said to be no greater than in the case of black powder. Sir A. Noble says in this connection: "It is almost unnecessary to explain that freedom from rapid erosion is of very high importance in view of the rapid deterioration of the bores of large guns when fired with charges developing very high energies. As might perhaps be anticipated from the higher heat of balli

es.|Foot Secs.| | | | | | | |With cordite 0.4 in. diam. | 2,794 | 2,940 | 3,166 | 3,286 | | " " 0.3 " | 2,469 | 2,619 | 2,811 | 2,905 | | " ballistite 0.3 in. cubes| 2,416 | 2,537 | 2,713 | 2,806 | | " French B.N. for | | | | | | 6-inch guns | 2,249 | 2,360 | 2,536 | 2,616 | | " prismatic amide | 2,218 | 2,342 | 2,511 | 2,574 | | | | | | | |____________________________|__________|__________|__________|__________| | | | ENERGIES REPRESENTED BY ABOV

these guns, so far as I can judge, the erosion is certainly not greater than with ordinary powder, and differs from it remarkably in appearance. With ordinary powder a gun, when much eroded, is deeply furrowed (these furrows having a great tendency

harge, 48 lbs. powder; b, charge, 13 lbs. 4 oz. cordite; c, charge, 13 lbs. 4 oz. pow

e seen upon reference to Fig. 39, which is taken from Professor V.B. Lewes's paper, read before t

s only about half the erosive effect of the old service cordite. With regard to the heating effect of cordite and cordite M.D. on a rifle, Mr T.W. Jones made some experim

., says that there is no doubt that the effect of heat upon cordite is greater than upon black powder. At

and when fired hot, the increase in pressure and velocities will depend upon the heat above the normal or average temperature at which firing takes place." Colonel Barker also, in referring to experiments that had been made in foreign climates, said: "Climatic trials have been carried out all over the world, and they have so far proved eminently satisfactory. The Arctic cold of the winter in Canada, with the temperature below zero, and the

It is claimed for this powder, that it does not corrode the barrel in the way cordite does, that with equal pressure it gives greatly increased velocity, and therefore flatter trajectory. That the effect of temperature on the pressure and velocity with axite is only half that with cordite. That the maximum flame temperature of axite is considerably less than that of cordite, and the erosive effect is therefore considerably less. That the deposit

dges with 200-

ty 2,7

re 20.

dges with 215-

ty 2,4

re 19.

ervice Ca

ty 2,1

re 15.

Service

ty 2,0

re 15.

in an oven and heated to a temperature of 110° F. for one hour, and

.~ ~Co

tons per sq. in. 15

6.73 " "

__

97 = 6.1%

e Velo

ng 2,150 F.S

2,180

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.S. = 1-1/2%

vered by a penny piece, the other being just outside. In order to ascertain the relative heat imparted to a rifle by the explosion of axite and cordite, ten rounds each

MPERATURE OF T

ite was

rdite w

favour of axit

th the cordite cartridge. The mean velocity of the first series of cordite cartridges was 1,974 ft. per second; the mean velocity of the second series was 2,071 ft. per second; the increased velocity due to the lubricating effect of axite therefore was

and the resulting compound afterwards passed between steam-heated rollers, and formed into sheets, which were then finally cut up into small squares or other shapes as convenient. The camphor contained in this substance was, however, found to be a disadvantage, and its use discontinued. The composition is now 50 per cent. of soluble nitro-cotton

fterwards put through a cutting machine and granulated. Sir A. Nobel's experiments[A] with this powder gave the following results:-The charge used was 5 lbs. 8 oz., the size of the cubes being 0.2 inch. The mean crusher-gauge pressure was 14.3 tons per square inch (maximum, 2,210; minimum, 2,142), and average pressure 2,180 atmospheres. The muzzle velocity was 2,140 foot seconds, and the muzzle energy 1,429 foot tons. A gramme of ballistite generates 615

c. Roy. Soc., vo

water, and to this solution is added the mixture of nitro-celluloses and calcium carbonate with constant stirring until the entire mass becomes a homogeneous paste. This pasty mass is next spread upon trays and re-dried at a temperature between 38° and 48° C., and when thoroughly dry it is transferred to the kneading machine. The ether- alcohol mixture is now added, and the process of kneading begun. It has been found by experiment that the amount of solvent required to secure thorough incorporation is about 500 c.c. to each 500 grms. of dried paste. To prevent loss of solvent due to evaporation, the kneading machine is made vapour light. The mixing or kneading is continued until the resulting greyish-yellow paste is absolutely homogeneous so far as can be detected by the eye, which requires from three to four hours. The paste is next treated in a preliminary press (known as the block press and is actuated by hydraulic power), where it is pressed into a cylindrical mass of uniform density and of such dimensions as to fit it for the final or powder press. The cylindrical masses from the block press are transferred to the final press, whence they are forced out of a die under a pressure of about 500 lbs. per square inch. As it emerges from the final press the powder is in the form of a ribb

. Walke, "Lectures on

surface, and are free from internal blisters or cracks. The temperature of ignition of the finished powder should not be below 172° C., and when subjected t

to solid threads, or tubular cords or cylinders, according to the calibre of the gun in which the powder is to be used. As the threads emerge from the press they are received upon a canvas belt, which passes over steam-heated pipes, and deposited in wire baskets. The larger cords or cylinders are cut into the proper lengths and exposed upon trays in the drying-house. The powder for small arms is granulated by cutting the threads into short cylinders, which are subsequently tumbled, dusted, and, if not perfectly dry, again placed upon trays in the drying- house. Before being se

hich consisted of nitrated paper 15 parts, mixed with 85 parts of unconverted cellulose. It was rolled into a cylinder. Another was Punshon's gun-cotton powder, which consisted of gun-cotton soaked

rsham, was at first intended for use as a g

nvention of Colonel Schultze, of the Prussian Artillery, and is now manufactured by the Schultze Gunpowder Company Limited, of

o-lignine 14

ble "

unconvert

of K and

fin 3

uble in alc

ure 2

was at once introduced into England, and the Schultze Gunpowder Company Limited was formed to commence its manufacture, which it did in the year 1868. During the years from its first appearance, Schultze gunpowder has passed through various modifications. It was first made in a small cubical grain formed by cutting the actual fibre of timber transversely, and then breaking this veneer into cubes. Later on improvements were introduced, and the wood fibre so produced was crushed to a fine degree, and then reformed into small irregular grains. Again, an

ution this Company has adhered to the first idea of using woody fibre in preference to cotton as the basis of their smokeless powder, as experience has confirmed the original opinion that a powder can be thus made less sensitive to occasional differences

cture of this powder

his nitro compound is carefully purified until it stands the very high purity requirements of the Home Office, and is then ground with oxygen-bearing salts, &c., and the whole is formed into little irregular-shaped grains of the desired size, which grains are dried and hardened by

r; this charge is 42 grains of powder and 1-1/8 oz. No. 6 shot-this shot fired from a

ity of Schultze gunpowder

ds ditto is 875

s ditto is 1,050

essure not to e

r in gravity; 33 grains occupies the bulk charge, as compared with the 42 grains of the old. It follows in its

orm of cellulose, derived from cotton, carefully purified, and freed from all foreign substances, and carefully nitrated. Its manufacture is somewhat as follows:-Pure nitro-cotton, in the form of a fine powder, is rotated in a drum, sprinkled with water, and the drum rotated until the nitro-cotton has taken the form

powder, that is to say, the old standard charge of 3 drams by measure for a 12-bore gun weighs 33 grains, as compared with 42 grains for the original E.G. and other nitro powders. This improvement was effected by a reduction of th

continually subjected to severe trials for stability under various conditions of storage, the result being that it may be kept for what in practice amount to indefinite periods of time, either in cartridges or in bulk without any alteration being feared. The E.C. powders are used in sporting guns. No. 1 and No. 2 E.C. are not at present manuf

mean velocity between any two points, and from its simplicity and accuracy is largely employed. Ot

5 parts of lycopodium powder, and 4 parts of urea crystals dissolved in acetone. The French smokeless powder, Vielle poudre (poudre B), used in the Lebel rifle, is a mixture of nitro-cellulose and tannin, mixed with barium and potassium nitrates. It gives a very feeble report, and very little bluish smoke. The Nobel Company is said to be perfecting a smokeless pow

se with many nitro powders. For this same reason, as well as from the method of getting rid of the solvent used, the Walsrode has no tendency whatever to absorb moisture. In fact, it can lie in water for several days, and when taken out and dried again at a moderate te

es for sporting purposes, an extra felt wad is required to compensate for the small space occupied by the charge; but for military use the powder can be left quite loose. The gas pressure of this powder is low (in several military rifles only one- half that

nd the skin produced retards burning. The nitro-cotton is mixed with acetic ether, and when the gelatinisation has taken place, the plastic mass is forced through holes in a metal plate into strips, which are then cut up into pieces t

thout nitrates, treated with a solvent to form a gelatinised mass. There are a great many varieties of this powder. One kind is in the form of little squar

edients. It is claimed for this powder that it combines hard shooting with safety, great penetration, and moderate strain on the gun. It is hard and tough in grain, and may be loaded like black powder, and subjected to hard friction without breaking into powder, that it is smokeless,

details of cannonite, s

Tonbridge, is shortly as follows:-The gun-cotton, which is the chief ingredient of this powder, is first stoved, then mixed with certain compounds which act as moderators, and after the solvents are added, is worked up into a homog

of the grains which, when looked at under the microscope, have the appearance of coke. The charge for a 12 bore is 33

of nitro-cellulose, nitro-be

paque, and rough to the touch. It consists of a mixture, nitro-cellulose

tro-cellulos

tro-cellul

nitrate

m nitrat

carbona

e matte

's powder invented for use in the Lebel rifle, and which c

pure gelatinised nitro- cellulose, together

a mixture of gelatinised nitro-ce

position and method of manufacture are, however, kept secret. It is made by the Columbia Powder Manufacturing Com

o-glycerine and nitro-cellulose, with amyl acetate as solvent. Its composition has, however, been altered from time to time. One variety consists chiefly of nit

a nitro-cel

guns of 8.4 calibre, it is used in the form of cylindrical grains of a yellow colour, of a diameter of .8 to .9 mm. and density of .790-about 840 grains of it go to one gun. For rifles, it is used in the form of grey squares, density .750

lar, when fired gave a muzzle velocity of 1,450 ft. secs. and pressure of 1,312 atmospheres, and the moisture was found to have risen from 1.2 to 1.6 per cent. After twenty-three months in the damp it contained 2 per cent. moisture, gave a muzzle velocity of 1,478 ft. sees., and pressure of 1,356 atmospheres. In a 7.5 millimetre rifle, 13.8 grm. bullet, and ch

on 96.21

cotton

ated cot

other matt

__

0.

treated first with acids and afterwards with alkalies, and the result is a firm fibrous substance which is granulated. It is claimed that this powder i

by Mr E.J. Ryves contain nitro- glycerine, nitro-cotton, castor-oil, paper-pulp, and carbonate of magnesia. Maxim powder contains both soluble and insoluble nitro- cellulose, nitro-gly

nown as the "Snyder Explosive," consisting of 94 per cent. nitro-glycerine, 6 per cent. of soluble nitro-cotton, and camphor, which is said to be safe in use. Experiments were made with it in a 6-inch rifled gun, fired at a target

pattern, and penetration were taken at 40 yards from the muzzle of a 12-gauge choke-bore double-barrel gun. Gas pressure was taken by a special apparatus. All shells were loaded with 1-1/8 oz. of No. 3 shot, equal to 120 pellets, and the number given below represents the average number in the 30-inch pattern. The number of sheets passed through gives the average penetration. O

| | | | | |powder, standard | | | | | |charge | 514.2 | 280 | 78.6 = 66% | 19.O | | | | | | | |Coarse-grained | | | | | |black powder, | | | | | |standard charge | 473.4 | 281.4 | 78.2 = 65% | 19.4 | | | | | | | |Schultze powder, | | | | | |42 grains | 921.0 | 290.0 | 64.2 = 54% | 20.2 | | | | | | | |Schultze

rmometer, 30° C. Hydro

to 1), and 70 parts of fused and pulverised picric acid. The ether-alcohol mixture is allowed to evaporate spontaneously, and the resulting cake granulated. The French claim, however, that the original invention has been so modified and perfected that the melinite of to-day cannot be recognised in the earlier product

h service, is supposed to be identical with the original

he Japanese powder, is s

ite (Chem. Centr.

a mixture of 54 parts of picrate of ammonia and 45 parts of saltpetre. It is stable and safe to manufacture. It has b

ee varieties, viz., for rifles, big guns, and torpedoes and shells. These powders are made much in the same way as gunpowder. The advantages

cid dissolves with the evolution of red fumes. The liquid, when cooled, deposits crystals, stated to be different to picric acid, and lustrous flakes. These flakes, when heated in water, s

powder. When tested against explosive gelatine, it did very good work in shattering iron plates. It is claimed for this explosive that it enjoys the distinction of being the only high explosive which may be used both for firearms and blasting. This view

has the form of a coarse yellowish grey powder, and leaves an oily stain on paper, and it is very sensitive to friction and percussion. The composition is as follows:-KClO_{3} = 80 parts; picric acid, 110 parts; saltpetre, 10 parts; charcoal,