EXPLOSIVES USED IN GRENADES
Explosives are divided into two classes:
- 1. Low explosives.
- 2. High explosives.
To the first group belong all propellant explosives, i.e., all powders, such as gunpowder and smokeless powders used in firearms.
To the second group belong:
- (a) All explosives used in shells, torpedoes, grenades,
- demolitions, etc.
- (b) Detonators or exploders, i.e., explosives which start
- explosive reactions in the explosives of Group (a).
The characteristic of H.E. is the extreme violence and suddenness of their detonation.
In order to make them instantly pass from a solid or liquid form to gas, they require a detonator or exploder, which applies a violent shock to them and breaks down the chemical structure of the explosive compound, and enables the flame to pass instantaneously throughout the mass of the compound. This explosive is known as detonation.
The composition of H.E. almost without exception is some organic substance, usually some form of carbon combined with nitrogen. Nitrogen, one of the most inert gases known, owes its explosive value to this very inertness; it combines so very reluctantly that on the least provocation—such as shock—the compound of which it forms a part instantly breaks up into gas, giving the enormous expansion needed for explosive effect.
Ammonal. A gray powder. An Austrian explosive, picric acid plus T.N.T. plus aluminum powder plus nitrate of ammonia plus carbon.
A very safe explosive—will not detonate when struck by rifle bullet, but is very hygroscopic (collects moisture) and when in this condition is liable not to detonate.
Ballistite. Consists of guncotton plus camphor or vaseline. Invented by Nobel in 1888.
Cordite. Consists of nitro-glycerine 55 parts, plus guncotton 37 parts, plus vaseline 5 parts, plus acetone to harden, invented by Sir W. Abel.
Benzol. Or Benzine, used extensively as a motor fuel contains a fair percentage of toluene. (See T.N.T.)
Coal Tar. When subjected to fractional and low-temperature distillation produces many by-products valuable in the making of H.E. These distillations give off “light” and “heavy” oils of coal tar.
Donnerite. High explosive employed by German army in grenades.
Dynamite. See Nitro-glycerine.
Fulminate of Mercury. See Mercury.
Guncotton, or nitro-cellulose consists of cotton waste, purified, dried, and heated with mixture of concentrated nitric and sulphuric acid. Washed and reduced to a pulp and moulded into 1 oz. primers and 15 oz. slabs for service use. Is considered inferior to lyddite.
- Size of wet slab of G.C., 6 × 3 × 1⅜ in.
- Wet guncotton will not explode if hit by a bullet.
- Wet guncotton can be sawn by a wet saw.
- Requires dry primer, detonator and fuse to explode.
- Dry guncotton will explode if hit by a bullet.
- Dry primer of guncotton 1.35 in. diam., 1.15 in. diam. at ends, and 1.25 in. high.
- Strength, 2½ times stronger than gunpowder, unconfined.
- Strength, 7 to 8 times stronger than gunpowder, confined.
- Invented by Schombein in 1846.
Gunpowder. A mechanical mixture.
Saltpeter 75 per cent, plus charcoal 15 per cent, plus sulphur 10 per cent. Rate of burning depends upon firmness of powder.
Lyddite, or picric acid. Consists of melted and solidified picric acid. Vaseline is used to melt it. (See Picric Acid.)
Mercury Fulminate. Is made by dissolving three parts mercury in 36 parts nitric acid, keeping mixture at low temperature, and when dissolved adding 17 parts of alcohol.
A small quantity of F. of M. placed on top of T.N.T. forms an excellent detonating mixture. A great many German detonators consist of this. Discovered by Howard in 1800.
Melinite. A French H.E., very similar to lyddite. Is picric acid mixed with collodion. Introduced by Eugene Turpin.
Nitro-glycerine. Is produced by the action of nitric acid and sulphuric acid on glycerine. Invented in 1847. When pure is a colorless liquid. Explodes when heated to about 360° F.
N.G. in liquid form too dangerous to be used in practice. Was absorbed in porous solid by Nobel in 1867 as dynamite. Porous solid used either kiesulguhr or fullers’ earth used in percussion caps.
| Relative strength | 150 equals maximum |
| Blasting glycerine | 150 |
| Gelatine dynamite | 130 |
| Gelignite | 110 |
| Dynamite | 100 |
| Carbonite | 55 |
Picric acid. A yellow crystalline prepared from coal tar. A by-product of gas manufacture. The “heavy oil” of coal tar is boiled and chemically treated, resulting in phenol or carbolic acid, which separates from it. Carbolic acid is boiled sulphuric acid, and nitric acid is carefully added, resulting in picric acid.
It is a very safe explosive and very powerful. Its chief fault is that it forms “picrates” with metals or acid salts, some of which are more sensitive to disturbing influences than the acid itself. To overcome this the inside of all shells are varnished.
Pressure of picric acid equals 135,820 lb. on the square inch.
Shimose. Japanese H.E. Similar to lyddite.
T.N.T., or tri-nitro-toluene or Toluol, largely used in German army and navy. Is produced by heating toluene with mixture of nitric and sulphuric acid.
Less powerful than lyddite, but is more stable and does not form “picrates” and is not affected by water or air. Will not explode if hit by a bullet.
Pressure T.N.T. equal to 119,000 lbs. per square inch.
Tolite. French name for T.N.T.
Trilite. Spanish name for T.N.T.
Trotyl. German name for T.N.T.
Toluene, or Toluol. Experiments made in 1899 at Karlsruhe produced about seven pints of toluene from one ton of coal. The modern process of low-temperature distillation of coal, however, greatly increases quantity that can be obtained from each ton.
Is an aromatic colorless liquid hydrocarbon.
Turpinite. French H.E. similar to Melinite.
Tetryl. A coal tar product containing more nitrogen than T.N.T. or lyddite. When mixed with a lead oxide it makes a less sensitive and safer preparation than fulminate of mercury for detonators.