C-4 (explosive)

C-4
Inserting blasting caps into blocks of C-4 explosive
Type	High-yield chemical explosive
Place of origin	United Kingdom
Service history
Used by	United States
Wars	Vietnam War War on Terror
Production history
Designed	1956
Produced	1956–current
Variants	PE-4, M112
Specifications (M112)
Weight	1.25 lb (0.57 kg)
Length	11 in (28 cm)
Width	2 in (5.1 cm)
Height	1.5 in (3.8 cm)
Filling	RDX
Filling weight	91%
Detonation mechanism	PETN-based detonating cord
Blast yield	High

C-4 or Composition C-4 is a common variety of the plastic explosive family known as Composition C. The British version of the explosive is known as PE-4 (Plastic Explosive). C-4 is composed of explosives, plastic binder, plasticizer to make it malleable, and usually a marker or odorizing taggant chemical.

C-4 has a texture similar to modeling clay and can be molded into any desired shape. C-4 is stable and an explosion can only be initiated by the combination of extreme heat and shock wave from a detonator.

The Composition C-4 used by the United States Armed Forces contains 91% RDX ("Research Department Explosive", an explosive nitroamine), 5.3% dioctyl sebacate (DOS) or dioctyl adipate (DOA) as the plasticizer (to increase the plasticity of the explosive), 2.1% polyisobutylene (PIB, a synthetic rubber) as the binder, and 1.6% of a mineral oil often called "process oil." Instead of "process oil," low-viscosity motor oil is used in the manufacture of C-4 for civilian use.

Technical data according to the Department of the Army follows.

C-4 is manufactured by combining the above ingredients with binder dissolved in a solvent. Once the ingredients have been mixed, the solvent is extracted through drying and filtering. The final material is a solid with a dirty white to light brown color, a putty-like texture similar to modeling clay, and a distinct smell of motor oil.