Shaped-charge grenade as a cutaway model, 1971

This hollow-charge grenade with a caliber of 105 mm was produced in 1971 and used in the Leopard 1, for example. This type of ammunition achieves its optimum effect against armored targets, but it can also be used against fortified positions, buildings or so-called soft targets, such as infantry soldiers or unarmored vehicles. This grenade was converted into a cutaway model in order to make the individual components recognizable. Such cutaway models are still used today in the training of soldiers.

The black, pellet-shaped propellant charge, which propels the projectile through the gun barrel after firing and accelerates it to a speed of more than 1,000 meters per second, can be seen at the bottom of the brass case. The silver wing stabilizer can also be seen there, which stabilizes the trajectory of the projectile head after leaving the barrel and minimizes the spin. When the projectile hits the target, the impact fuse is triggered, which in turn triggers the base fuse via a cable. This energy inverts the copper-colored funnel of the shaped charge forwards and cold-forms it into a superplastic spike.

This hollow-charge sting hits the target at up to 12,000 meters per second, penetrates the steel and displaces it hydrodynamically to the side and inwards. If the armor is penetrated completely, pressure, heat, gases, smoke and splinters penetrate the interior of the enemy tank.

The shaped charge effect was already described in Germany in 1888 and used in mining. This type of ammunition has been used by the military since the late 1930s, but the physical processes were not properly analyzed until 1948. In the 1950s, the distance fuse was added at the tip, which ensures that the shell is triggered at the ideal distance from the armor in order to achieve the best possible penetration performance. The armor was then also further developed, with material mixtures and cavities reducing the effect of the shaped charge, which is why, for example, ceramic plates, spaces with air or sand or sandwich armor made of different hard materials were used.

In NATO, shaped-charge grenades are referred to as “HEAT”, which stands for “High Explosive Anti-Tank”.