Penetration Performance of a Calibre 5.56 mm Tungsten-Rhenium AP-Projectile into Steel and Ceramic Targets

Abstract

The AP3 (US M995) calibre 5.56 mm projectile contains a core made of cemented carbide. The high hardness of this material facilitates rigid body penetration in most types of metal targets. On the other hand, in a ceramic target, the ceramic has a hardness equalling or exceeding that of the cemented carbide and the core will deform and shatter instead of stay rigid. Since the performance of a deforming projectile core depends on both inertia and the strength, a hypothesis is that a higher density may be able to compensate for lower strength or even be more favourable when defeating this type of targets. In order to study this, projectiles with cores made of tungsten-26% rhenium with a density of 19.7 g/cm3 have been tested. The geometry of the W26Re was made identical to the cemented carbide core in the Nammo AP3 projectile. The penetration performance of the W26Re projectile and the original projectile was tested against two different target types: a simplified ceramic armour structure and a single steel armour plate. The performance was evaluated by establishing the ballistic limit velocity for each target and projectile combination.