C-4
Definition
US military standard plastic explosive containing approximately 91% RDX in a di(2-ethylhexyl)sebacate and polyisobutylene binder. White, odourless, malleable. Detonation velocity 8,050 m/s. Standard demolition charge M112: 567 g.
- Composition
- Approx. 91% RDX in sebacate/polyisobutylene binder
- Appearance
- White, odourless, malleable putty
- Detonation velocity
- 8,050 m/s
- Standard charge
- M112 block, 567 g
Common questions
What residue signature helps identify C-4 at a post-blast scene?+
Because C-4 is almost pure RDX with a small amount of plasticiser binder, post-blast debris and swabs analysed by techniques such as GC-MS or ion mobility spectrometry that detect RDX with little or no TNT or PETN alongside it point toward C-4 rather than a mixed military or improvised explosive.
How does C-4 differ from Semtex in forensic terms?+
Both are RDX-based plastic explosives, but Semtex traditionally contains a mixture of RDX and PETN together, while C-4 is essentially RDX alone. The presence or absence of PETN in post-blast residue is one indicator examiners use to distinguish the two.
Related terms
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- The localised shattering effect of a detonation shock wave, measured by the Trauzl lead block test or the sand-crush test. RDX and...
- Composition B (Comp B)
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- Detonating Cord (Det Cord)
- A flexible tube containing a PETN explosive core at a standard linear charge density (3.6 g/m for No. 2 cord). Propagates detonation...
- DMDNB
- 2,3-Dimethyl-2,3-dinitrobutane, the primary detection taggant mandated by the 1991 ICAO Convention on the Marking of Plastic Explosives. Required at 0.1% by mass...
- GC-ECD
- Gas chromatography with electron capture detection. Achieves 1-10 picogram detection limits for nitroaromatic (TNT, DNT) and nitramine (RDX, HMX, PETN) explosives. Cannot...
- ICAO Montreal Protocol on Plastic Explosives (1991)
- The Convention on the Marking of Plastic Explosives for the Purpose of Detection, adopted by ICAO following the Lockerbie and UTA bombings....
- LC-MS/MS (Negative ESI)
- Liquid chromatography with tandem mass spectrometry in negative-ion electrospray ionisation mode. Confirmatory method for all conventional secondary explosives and the primary method...
- Oxygen Balance
- A percentage expressing the surplus or deficit of oxygen in an explosive molecule relative to stoichiometric complete oxidation of carbon to CO2...
- Semtex H
- A plastic explosive manufactured by Explosia a.s. (Czech Republic) containing approximately 41% PETN and 41% RDX in a styrene-butadiene rubber binder. Identified...