C-4 (explosive)
C-4 or
Composition C-4 is a common variety of military
plastic explosive.
C-4 is made up of
explosive, plastic binder,
plasticizer and, nowadays, marker or
taggant chemicals such as 2,3-dimethyl-2,3-dinitrobutane (
DMDNB) to help detect the explosive and identify its source. As with many plastic explosives, the
explosive material in C-4 is
RDX (also known as cyclonite or cyclotrimethylene trinitramine) which makes up around 91% of the C-4 by weight. The plasticizer is di(2-ethylhexyl) or
dioctyl sebacate (5.3%), and the binder is
polyisobutylene (2.1%). Another binder used is
dioctyl adipate (DOA). A small amount of
SAE 10 non detergent motor oil (1.6%) is also added. C-4 detonates at about 26,400 feet per second (fps). This is about 7,400 fps faster than commercial 60%
dynamite.
C-4 is made by combining
RDX slurry with binder dissolved in a solvent. The solvent is then distilled away and the mixture is dried and filtered. The final material is an off-white solid which has a similar feel to modelling clay.
The explosive is a
1960s improvement on a British
World War II development called
Nobel 808 which contained
RDX,
mineral oil, and
lecithin. C-4 is part of a group of explosives along with C,
C2 and
C3, each containing different amounts of RDX.
The C does not stand for
composition; the name is not an abbreviation of
Composition 4. The term
composition is used for any stable explosive, and "Composition A" and "Composition B" are other known variants. Therefore, C-4 is correctly referred to as
Composition C-4.
A major advantage of C-4 is that it can easily be moulded into any desired shape. C-4 can be pressed into gaps/voids in buildings, bridges, equipment or machinery. Similarly, it can easily be inserted into empty
shaped-charge cases of the type used by special forces. C-4 is also well known for its durability and reliability. It will not explode even if hit by a bullet, punched, cut, or thrown into a fire. The only reliable method for detonation is via a
detonator or
blasting cap. However, applying pressure in combination with heat can often cause detonation.
When the military or a demolition company uses C-4 they normally use 8â€"10 pounds of C-4 to demolish eight inch square steel beams, even though this is more explosive than is required. They do this to make sure that they have accomplished the job successfully.
British plastic explosive is referred to as PE4. Like C-4 it is an off-white coloured solid and its explosive characteristics are nearly identical. The only difference between C-4 and PE4 is the type and proportion of plasticizer used.
A plastic explosive called
Semtex is the Eastern European equivalent of C-4.
C-4 is 1.36
times as explosive as
Trinitrotoluene* C-4 was used in the finals of the 1995 "FMW King of the Deathmatch." The match took place between
Mick Foley and
Terry Funk. The "King of the Deathmatch" was a
professional wrestling tournament held in
Japan. Death match winner
Mick Foley received second degree
burns from this explosion.
* Because C-4 burns slowly if a started explosion is not feeding it, during the
Vietnam War era, many soldiers would use small amounts of C-4 as means of heating rations while on long patrols. While many soldiers were able to use C-4 in this manner safely, there are several anecdotes about soldiers attempting to put out the fire by stomping on it and causing it to detonate.
* C-4 is a typical explosive used in many movies, TV shows and video games.
* Because C-4 is a modeling-clay like substance, it is especially useful in blowing up doors and safes. Many movies show C-4 being used in this way.
*
HowStuffWorks article* [https://www.tbs.usmc.mil/Pages/Training%20Corner/sho's/R/BOR3405%20Engineering%20Skills%20Field%20Firing%20Exercise.doc Student Handout (.doc)] From the U.S. Marine Corps, includes a table on explosive power (on page 2).
