Composition B

Composition B, colloquially "comp B", is an explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenades, sticky bombs and various other munitions.[1] It was also used for the explosive lenses in the first implosion-type nuclear weapons developed by the United States.

Ingredients

The standard ratio of ingredients (by weight) is 59.5% RDX (detonation velocity of 8,750 m/s) and 39.4% TNT (detonation velocity of 6,900 m/s), together with an additional 1% paraffin wax[4] to improve handling qualities. Most commonly it is described as 60/40 RDX/TNT with 1% wax added.
Properties

Density: 1.65 g/cm3-
Velocity of detonation: 8,050 m/s
Use

Composition B was extremely common in United States and other western nations' munitions and was the standard explosive filler from early World War II until the early 1950s, when less sensitive explosives began to replace it in many weapons systems.[citation needed] Some NATO-approved munitions suppliers such as Mecar[5] have continued to use Composition B in their products.
Composition B is related to Cyclotol, which has a higher proportion of RDX (up to 75%).