The influence of the mechanical properties on the penetration performance of a model scale KE-projectile has been studied experimentally. Two different tungsten materials, Y925 and DX2M with very different mechanical properties were used as projectile materials. The projectiles were slender cylinders with either flat or spherical noses. The impact velocity was the same in all tests, 1800 m/s, and the target was an oblique plate with 60° obliquity and one projectile diameter thickness. The experiments showed that the projectile with a flat nose either fractures or deforms plastically depending on material. The spherical nose shape resulted in large scatter in the projectile behaviour and no clear influence of the projectile material could be observed.