The authors performed deep punching experiments on PMMA (polymethyl methacrylate) using cylindrical-shaped punches with conical and hemispherical noses. The test samples cracked when no lateral confinement was provided. Application of proper lateral confinement suppressed the cracks. The punching force recorded from the experiments correlates very well with cavity expansion theory. Because the use of a single friction coefficient gives excellent agreement between theory and experiments for two different-shaped punches, the authors propose deep punching as a new technique to measure the friction coefficient.