Salient. Victoria University Student Newspaper. Volume 36, Number 8. 19th April 1973
Shaped Charge
Shaped Charge
General, A shaped charge is designed to concentrate the energy of the explosion on a small area to make a tubular or linear fracture in the material on which it is placed. The versatility and simplicity of shaped charges makes them an effective weapon, especially against armor plate and concrete. Shaped charges are easily improvised.
(a) | The angle of the cavity (cone) should be between 30 degrees and 60 degrees. |
(b) | The stand-off distance (distance from the bottom of the shaped charge to the target) should be from 1 to 2 times the diameter of the cone. |
(c) | The height of the explosive content, measured from the base of the cone, should be twice the height of the cone. |
(d) | The detonation point should be exact top center. |
(e) | An ogive must be used if charge is placed underwater. |
Grenades (fig. 8). A simple grenade can be constructed by the use of a 0.225-gram block of explosive, scrap metal, time fuse, and non-electric cap. The time fuse is used as the delay element. Bolts, nuts, nails, or other pieces of metal are secured to the grenade for fragmentation effect. A small metal pipe may also be used as the grenade jacket. The grenade is detonated by a nonelectric blasting cap crimped to a short piece of time fuse, Insert the blasting cap into the explosive and tie or tape it firmly in place. Small V-notches are cut Into the fuse. As the time fuse burns, a spurt of flame appears at the V-notches. After the flame appears at the last V-notch, the grenade is thrown. If desired, only one V-notch (closest to the cap end) may be used- The V-notches should be taped to keep out moisture.
Dust Initiator (fig. 9). The dust initiator is used to destroy buildings and certain storage facilities. The basic purpose of this device is to achieve two distinct but rapidly successive explosions. This is accomplished by constructing a main charge composed of equal amounts of powedered TNT (obtained by crushing TNT in a canvas bag) and magnesium powder and inclosing it in a cover charge of a scattering agent of any carbonaceous material which can be reduced to dust vapor. Examples are cornstarch, flour, coal dust, or gasoline (when using gasoline, never use more than 11.4 liters.) Thermite may be substituted for magnesium in the mixture. From 1.36 to 2.67 kilograms of surround should be provided for each 28.32 cubic meters of targets The 0.45 kilograms (0.225 Kilograms TNT and 0.225 kilograms magnesium powder) charge will effectively disperse and detonate up to 18.14 kilograms of carbonaceous material. Upon activation, the main charge detonation distributes the cover charge material, which is initiated by the action of the incendiary explosion. This causes the entire atmosphere to be saturated with burning materials. The destructive effect of this device is increased by closing all windows and doors in the target building. This charge may be detonated elcctrically or non-electrically.