Composition B (Comp B), also known as Hexotol and Hexolite (among others), is a high 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, 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. [2] [3]
The standard proportions of ingredients (by weight) are 59.5% RDX (detonation velocity of 8,750 m/s) and 39.5% TNT (detonation velocity of 6,900 m/s), phlegmatized with 1% paraffin wax. [4] Most commonly it is described as 60/40 RDX/TNT with 1% wax added.
Composition B was extremely common in Western nations' munitions and was the standard explosive filler from early World War II until the early 1950s, when less sensitive explosives such as Composition H6 began to replace it in many weapons.[ citation needed ] M65 bombs from 1953 containing degraded Composition B were responsible for much of the damage in the 1967 USS Forrestal fire.
Some NATO-approved munitions suppliers such as Mecar 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%).
IMX-101 is slowly replacing Comp B in US military artillery shells, and IMX-104 [5] in mortar rounds and hand grenades.
RDX (abbreviation of "Research Department eXplosive" or Royal Demolition eXplosive) or hexogen, among other names, is an organic compound with the formula (CH2N2O2)3. It is white, odorless, and tasteless, widely used as an explosive. Chemically, it is classified as a nitroamine alongside HMX, which is a more energetic explosive than TNT. It was used widely in World War II and remains common in military applications.
An explosive is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An explosive charge is a measured quantity of explosive material, which may either be composed solely of one ingredient or be a mixture containing at least two substances.
Trinitrotoluene, more commonly known as TNT (and more specifically 2,4,6-trinitrotoluene), and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagent in chemical synthesis, but it is best known as an explosive material with convenient handling properties. The explosive yield of TNT is considered to be the standard comparative convention of bombs and asteroid impacts. In chemistry, TNT is used to generate charge transfer salts.
A shaped charge is an explosive charge shaped to focus the effect of the explosive's energy. Different types of shaped charges are used for various purposes such as cutting and forming metal, initiating nuclear weapons, penetrating armor, or perforating wells in the oil and gas industry.
High-explosive anti-tank (HEAT) is the effect of a shaped charge explosive that uses the Munroe effect to penetrate heavy armor. The warhead functions by having an explosive charge collapse a metal liner inside the warhead into a high-velocity shaped charge jet; this is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge. The shaped charge jet armor penetration effect is purely kinetic in nature; the round has no explosive or incendiary effect on the armor.
Amatol is a highly explosive material made from a mixture of TNT and ammonium nitrate. The British name originates from the words ammonium and toluene. Similar mixtures were known as Schneiderite in France. Amatol was used extensively during World War I and World War II, typically as an explosive in military weapons such as aircraft bombs, shells, depth charges, and naval mines. It was eventually replaced with alternative explosives such as Composition B, Torpex, and Tritonal.
A shell, in a military context, is a projectile whose payload contains an explosive, incendiary, or other chemical filling. Originally it was called a bombshell, but "shell" has come to be unambiguous in a military context. A shell can hold a tracer.
Insensitive munitions are munitions that are designed to withstand stimuli representative of severe but credible accidents. The current range of stimuli are shock, heat and adjacent detonating munitions. A munition can have its vulnerability reduced by a number of means used on their own or in combination such as a reduced vulnerability energetic material, design features, additions or changes to packaging etc. The munition must still retain its terminal effect and performance within acceptable parameters.
The Composition C family is a family of related US-specified plastic explosives consisting primarily of RDX. All can be moulded by hand for use in demolition work and packed by hand into shaped-charge devices. Variants have different proportions and plasticisers and include Composition C-1, Composition C-2, Composition C-3, and Composition C-4.
Cyclotol is an explosive consisting of castable mixtures of RDX and TNT. It is related to the more common Composition B, which is roughly 60% RDX and 40% TNT; various compositions of Cyclotol contain from 65% to 80% RDX. Typical ranges are from 60/40 to 80/20 RDX/TNT, with the most common being 70/30, while the military mostly uses 77/23 optimized in warheads.
A phlegmatizedexplosive is an explosive that has had an agent added to stabilize or desensitize it. Phlegmatizing usually improves the handling properties of an explosive
Octol is a melt-castable, high explosive mixture consisting of HMX and TNT in different weight proportions.
Minol is a military explosive developed by the Admiralty early in the Second World War to augment supplies of trinitrotoluene (TNT) and RDX, which were in short supply. The aluminium component in Minol significantly prolongs the explosive pulse, making it ideal for use in underwater naval weapons where munitions with a longer explosive pulse are more destructive than those with high brisance. Minol cannot be used in weapons fired from gun barrels because there is a risk of detonation when subjected to over 250 gs of acceleration. Initially, three Minol formulas were used. All percentages shown are by weight:
Composition H-6 is a melt-cast military aluminized high explosive. H-6 was developed in the United States.
Fragmentation is the process by which the casing, shot, or other components of an anti-personnel weapon, bomb, barrel bomb, land mine, IED, artillery, mortar, tank gun, or autocannon shell, rocket, missile, grenade, etc. are dispersed and/or shattered by the detonation of the explosive filler.
The F1 grenade is manufactured by Thales Australia exclusively for the Australian Defence Force as a primary defensive anti-personnel hand grenade.
In military munitions, a fuze is the part of the device that initiates its function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze designs can be seen in cutaway diagrams.
IMX-101 is a high-performance insensitive high explosive composite mixture developed by BAE Systems and the United States Army to replace TNT in artillery shells. IMX stands for "Insensitive Munitions eXplosives", which refers to the purpose of IMX-101: to provide explosive force equivalent to TNT without its sensitivity to shocks such as gunfire, explosions from improvised explosive devices, fire, and shrapnel. For example, it is believed that a training incident in Nevada which killed seven Marines would not have occurred with the new explosive. On March 23, 2013, the United States Army ordered $780 million worth of the explosive, with a production of millions of pounds annually, to be produced by BAE at Holston Army Ammunition Plant in Tennessee. The new explosive will cost $8 per pound, compared to $6 per pound for TNT. As of 2023, IMX-101 filled shells are being used in the 2022 Russian invasion of Ukraine.
The M549 is a high-explosive rocket-assisted (HERA) 155 mm howitzer round developed for use by the US military in order to add additional range to standard howitzers, with a maximum range 30.1 km (18.7 mi) from a M198 howitzer. The projectile has two distinctive pre-assembled components—the high-explosive (HE) warhead and the rocket motor, making it a form of rocket-assisted projectile. The warhead is fabricated from high-fragmentation steel for increased effectiveness in terms of damage caused to target and contains a bulk-filled explosive.