Plastic explosives

C-4 plastic explosive (the barely white rectangle blocks) being used to destroy unexploded fighting parts.

Plastic explosive is a softer solid form of explosive material. In the field of explosives engineering, plastic explosives are sometimes known as putty explosives.

Plastic explosives are mostly used for explosive destruction. Common plastic explosives include Semtex and C-4. The first made plastic explosive was gelignite in 1875, created by Alfred Nobel.

Composition C

The British used a plastic explosive during World War II for destruction. The material was plastic between 0 and 40 degrees C, but was breakable when colder and more liquid-like when it's very hot. Composition C2 had a bigger temperature range at which it would stay as plastic, from −30 to 52 degrees C. Composition C2 was replaced by Composition C3, which was a mixture of 77% RDX and 23% explosive plasticizer. C3 worked very well but proved to be too breakable in cold weather and was replaced with C4. There are three classes of C4, with differing amounts of RDX and polyisobutylene.

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  A 1.25 lb destruction charge of C4 explosive

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  A soldier makes a charge of C4 to cut through solid steel at a destructions range

Plastic Explosives Media

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  Disposal of munitions with plastic explosives; note the malleability of the white plastic explosive charges

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  PE4 sticks, used alongside the L3A1 slab version by the British armed forces prior to the adoption of the later L20A1 block/L21A1 slab PE7 and L22A1 slab PE8 explosives

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  Two blocks of Semtex-1H (note the characteristic orange color) and an American M112 charge containing C4