Frame sequences of impacts 2018-02-08-1, brass projectile at 1.3 m s⁻¹ into mm-sized grains (top) and 2017-08-30-2, glass projectile at 60 cm s⁻¹ into cm-sized grains (bottom). In these sequences, time elapses from left to right. The launcher is to the right of the image, and the projectile travels toward the target on the left. In early frames, the shim can be seen, which then retracts due to the launcher spring. On the first frames shown, the projectile is already traveling independently of the shim, which can assume angled positions after the launch without impacting the normal trajectory of the projectile.