Defin Hons and Terms

a. Adapter (Priming)* A plastic connector (fig. 40) used to connect detonating cord, safety fuse M700? time blasting fuse, or electric firing systems to a demolition block.

b. Blasting Cap. A 14-inch diameter (approx) metal tube or shell (figs. 38 ami 39) containing a high explosive used to detonate a less sensitive explosive. There are two types of blasting cap, electric and nonelectric. The electric type is fired by an electric current and the nonelectric type is fired by safety fuse M700, time blasting fuse, or a firing device. Tn the firing chain, the blasting cap is the element that fires the main charge, or, the blasting cap may be the element that initiates a detonating cord, which fires the main charge.

c. Blasting Machine, A small hand-operated magneto-type electric generator (fig. 43), which is used to fire electric- blasting caps. Push-down-type machines of 30-cap, 50-cap, and 100-cap capacities and a twist-type machine of 10-cap capacity are provided.

d. Block, Demolition. The term applied to a quantity (such as V2 lb, 1 lb, or 21,4 lb) (figs. 6 and 7) of high explosive, such as tetrytol or COMP C series explosives, to which a firing device or blasting cap with safety fuse or electric lead, whichever is applicable, may be attached for use in demolition work or as an improvised mine.

e* Breaching. The employment of any available means to secure a gap through an enemy mine field or obstacle.

/. Cable, Detonating. Especially designed demolition cable (figs. 62-66) composed of strands of detonating cord used for clearing mine fields.

g- Cap WelL Opening in demolition blocks and in certain types of mines, threaded to receive a firing device with blasting cap or io receive ail adapter to which a time blasting fuse and nonelectric blasting cap or electric leads and an electric blasting cap are to be attached.

h~ Cartridge. In demolition work, the correct term for a cylindrical piece of dynamite—sometimes popularly known as a ^stick^

of dynamite (fig. 15). The term "cartridge" is also sometimes used for an explosive element of a demolition snake.

i. Charge. Any amount of explosive required to accomplish a particular mission. A charge may vary in size from a few ounces to several thousand pounds.

j. Corrl% Detonating. A cord (lijp». 23 and 24) that contains a core of high-explosive, PET.N, wrapped in a plastic cover. The de-

Improvised Nonelectric Delay Devices

safety pin (positive)— remove last pressure type firing device i.----Vi>J4>

^pull type firing device-

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Figure ¿. Exploitive charyt with preuure-tyyc firing (twice ••activatedH icith Dulbtypr firing device safety pirut and fork to be removed after laying board lightly on prr**urr-ttfpe firing device.

Firing Device Demolition Booby Trap
Figure 3. Schcmatic arrangement of firing device tafrlie* and component m.

tonating cord, when properly initiated, explodes throughout its entire length, detonating any properly connected demolition charge or mine.

k. Coupling Base. A metal coupling (tig*. 27-36) containing a percussion primer and having a nipple to which a black powder igniter or blasting cap may be attached. The coupling base is threaded at one end to screw into a standard firing mechanism and at the other end to screw into a cap well of a demolition block or certain types of mines.

Crimper. Cap. This is a special plier-like tool (BB, fig. 47) used for cutting detonating cord, safety fuse, or time blasting fuse and for crimping a nonelectric blasting cap to detonating cord, safety fuse, or time blasting fuse, or crimping a blasting cap to the coupling base of a firing device. One handle of the crimper is pointed for making a hole in a dynamite cartridge: the other handle is flattened to form a screwdriver.

m. Demolition Material. The explosives, devices, and equipment used in demolition work. If conditions require, antitank mines may be used for demolition.

n. Detonation. Detonation is the reaction that takes places when a high-explosive is exploded. As the mass of high explosive is init iated, a detonating wave is created that progresses throughout the mass transforming it instantly into gases.

(1) Lotr-order detonation. The incomplete detonation of an explosive charge in a bomb, projectile, or other high explosive.

(2) riigh ord^r dttonntum. A complete and instantaneous explosion.

o. Detonaior. A device (ligs. 17-19), consisting of a primer composition charge and one or more additional high-explosive charges of different compositions, arranged in order of decreasing sensitivity and increasing quantity, used for exploding an explosive charge.

p. Explosive. Explosives are classified as low or high depending on the rate at which the reaction of explosion takes place. The rates of transformation of explosives into gas vary over a wide range.

(1) Low explosives as compared with high explosives One group of explosives, which includes propel 1 ant and black powder, is classified from the viewpoint of use characteristics as "burning*' explosives. This group undergoes autocom-bustion at rates that vary from a few centimeters per minute to 400 meters per second; these are known as low explosives-A second group, which includes TXT, Compositions A, B, and C, PETN, nitroglycerin, and many others, is classified from the viewpoint of use characteristics as "high" explosives. This group undergoes detonation at rates from 1,000 to 8,500 meters per second.

(2) Propellants. A propellant is an explosive {solid or liquid) that is suitable for effecting the controlled propulsion of a solid body such as a bullet, shell, rocket, blast-driven earth rod, or a moving pail in a mechanical device. As disruption of the propellant container must not take place and as the movement of the object propelled must be controlled, the explosive process of the propellant must be controlled. Because of these requirements, only low explosives are suitable for use as propel hints- However, some solid propellants are presently considered to be high explosives.

q. Firing Pin. A pointed metal plunger in the firing mechanism of a fuze or of a firing device (fig. 33) that, when released, strikes a sensitive explosive in a primer or detonator and explodes it. A firing pin is sometimes called a striker.

t\ Firing Device. A small metal case or body (figs. ¿7-36) containing a firing pin mechanism and primed coupling base to which a blasting cap, igniter, or activator may be attached. Firing devices are used to initiate the explosion of demolition blocks and as secondary antitank mine fuzes. A firing device is issued separately. When assembled with a detonator, it may be used as a mine fuze, anti-lift device, or to set oif prepared charges.

$. Firing Mechanism* That part of a firing device consisting of a firing pin assembly and its housing. t. Fnxe* Blasting* Time« Commercial-type waterproof cord (fig. that has a corrugated surface and contains a core of black powder and is fabricated to provide delay for safety purposes. It is sometimes called a safety fuse {ac below). It is used only with nonelectric blasting caps or black powder igniters {squibs). The burning rate of a 1-foot length should be tested before using.

it. Fuze. A mine fuze is a complete assembly issued with a mine.

It always contains a means of detonation and is normally used in primary fuze wells.

v. Fuze Well Opening in a demolition block to receive a firing device or other priming arrangement.

w. Galvanometer. An instrument (fig- 42) for determining whether there is any current and, therefore, whether the circuit is closed.

x, Kit. A specific collection of equipment, tools, and explosives (fig. 52) used for performing certain particular demolition tasks or with inert simulated explosives for training personnel. The term "kit" is also used to designate a group of items, which together are a component of a set.

y. Lighter, Fuze. A small tubular device containing a, friction compound and hand-pull friction wire or containing a firing pin and primer (figs. 20 and 21) ; used for attachment to and ignition of time blasting fuse or safety fuse M700, z. Primer. A small cylindrical metal casing (fig. 37), used in a firing device, containing an internal cup filled with a very sensitive high-explosive and an anvil arranged so that, when the cup (showing at one end of the primer) is struck by a firing pin, the explosive is detonated and flame is spurted from the other end for the purpose of exploding a detonator or an igniting charge. Primers may also be actuated by friction or electric spark, aa. Protector. Shipping. The small celluloid or cardboard cup-shaped cover (fig. 29) with which the nipple of the coupling base of a firing device is protected during shipment.

ab. Safeties. Organic safety devices (those incorporated in design) (fig, 3) characteristic of all fuzes and firing devices to help prevent accidental functioning. Their removal, as in the case of safety cotter pins, constitutes the process called "arming.'7

ac. Safety Fuse. Military-type waterproofed cord that has a smooth plastic cover and contains a core of black pow der and is fabricated to provide delay for safety purposes. It is marked at 18-inch intervals to correspond to a burning time of 1 minute. The 18-inch intervals are rough and provide a means for measuring the fuse in daylight and darkness. It is used only with nonelectric blasting caps or black powder igniters (squibs).

ad.. Set. A specific collection of explosives initiators, primers, equipment, and tools, used for performing particular demolition tasks or tasks supplementary thereto.

ae. Shaped Charge. A mass of high-explosive having a shaped metallic- or nomnetallic-lined recess that causes it to have a one-way penetrating action known as "MUNROE effect." It is used to blast boreholes in steel, concrete, or similar materials or may be used to penetrate explosive-filled objects to induce a low order functioning, if the shaped charge is of appropriate size.

af. Snake., Demolition. An elongated and somewhat flexible fabricated metal container having a pear-shaped guiding nose and a body containing high-explosive charges (fig. 67). The snake is assembled in the field and manipulated into position, by a tank, among various obstacles or in an enemy mine field and there exploded by appropriate fuze arrangements in order to clear a path for troops or vehicles. Upon functioning, a trough-shaped path some 325 feet long, 4 to 12 feet wide, and 2 to 4 feet deep is made, depending on the character of the soil.

ag. Sympathetic Detonation. One which is induced by the explosion of another charge.

ah. Torpedo, B&ngalore. An explosive device (fig. 10) consisting of any desired number of slim cylindrical explosive charges in metal containers. Any number of these containers may be attached to each other endwise. It is used against barbed wire and various other relatively light obstructions.

aL Destructor, High-Explosive^ Universal. The universal high-explosive destructor is a high-explosive charge initiated by means of blasting caps or mine activators and standard firing devices. It is used in preparing loaded projectiles and bombs as improvised mines, booby traps, and demolition charges. It is also used by disposal units to destrov deteriorated or abandoned ammunition.

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