The ballistic performance of Dyneema® HB26 and Spectra® 3124 subjected to high velocity impact of steel and copper Fragment Simulating Projectiles was evaluated. A 3D High Speed Digital Image Correlation was used for measurement of the panels front face deformation and the back face deformation. The information obtained from the measurements, along with the post-mortem observation of the panels, allowed to draw conclusions with respect to the importance of various energy dissipation mechanisms that occurred in the tested materials. It was observed that, although Dyneema® HB26 and Spectra® 3124 deform very differently during the impact event, they had a similar ballistic performance.