Editing Composition C (section)

==Characteristics and usage==
Composition C-3 was very similar to Composition C-1, but removed the solvent and varied the exact proportions of plasticisers to improve high temperature storage. It is a yellow, putty-like material. It remained a service item through the [[Korean War]], but had marginal plasticity at the very low temperatures encountered in Korean winters, and was significantly toxic, including by vapour and skin absorption.<ref name=Arb1MemoIsn841>{{cite web
| url=http://www.dod.mil/pubs/foi/detainees/csrt_arb/ARB_Round_1_Factors_000694-000793.pdf#7
| title=Unclassified Summary of Evidence for Administrative Review Board in the case of Nashir, Sa id Salih Sa id
| pages=7–9
| publisher=[[United States Department of Defense]]
| author=OARDEC
| author-link=OARDEC
| date=2005-11-23
| access-date=2008-12-07
| quote=The detainee was trained to use the [[Kalashnikov rifle]], [[rocket propelled grenade]]s, [[hand grenade]]s, [[land mine]]s, Composition-3 (C-3) and Composition-4 (C-4) explosives.
| archive-date=2008-12-01
| archive-url=https://web.archive.org/web/20081201020040/http://www.dod.mil/pubs/foi/detainees/csrt_arb/ARB_Round_1_Factors_000694-000793.pdf#7
| url-status=dead
}}</ref> While Composition C-3 had a much wider serviceable temperature range than Composition C-1, it could not be stored at elevated temperatures. Consequently, it would eventually be replaced by Composition C-4. The [[velocity of detonation]] is about 7600&nbsp;m/s (25,000 feet per second).

Composition C-3 consists of 77%–85% cyclonite ([[RDX]]) and 15%–23% gel made out of liquid nitro compounds (e.g. liquid [[dinitrotoluene|DNT]] and small amount of [[mononitrotoluene|NT]]) and nitrocellulose or butyl phthalate and nitrocellulose.<ref>{{cite book|title= Chemistry and Technology of Explosives
|author=Urbanski Tadeusz
|publisher= Pergamon
|location= Oxford
|year=1985
|edition= second
|orig-year= 1984
|others= Volumes I–IV
}}</ref>

One of the first reported and tested compositions of C-3 was very similar to earlier Composition C-2 and contained 77% [[RDX]], 3% [[tetryl]], 4% [[TNT]], 1% [[Nitrocellulose|NC]], 5% [[mononitrotoluene|NT]], and 10% [[dinitrotoluene|DNT]].<ref>
{{cite web
| url=http://www.globalsecurity.org/military/systems/munitions/explosives-compositions.htm
| title= Explosives - Compositions
| author=GlobalSecurity.org
| quote= Composition-3 (C-3) and Composition-4 (C-4) explosives, Semtex.
}}
</ref> The last two compounds (they are very poor explosives) are oily liquids and plasticise the mixture. The most important later innovation of C-3 introduced the non-explosive [[plasticiser]] butyl phthalate instead of this mixture of nitro compounds. This reduced the toxicity while increasing the concentration of [[RDX]] and improving safety of use and storage. It also opened the way to begin study of new non-explosive low-toxicity plasticisers (esters of dicarboxylic acid) and binder (branched [[polymers]]).