The behaviour of polymers under high strain-rate loading conditions remains insufficiently understood than their quasi-static response, despite their benefits in producing lightweight structural components and rapid prototyping. The study aimed to determine the compressive behaviour of a 3D-printed polymer, Nylon 12, under high strain-rate conditions using a conventional Split Hopkinson Pressure Bar (SHPB) apparatus. Cylindrical specimens were 3D printed by varying printing orientation (flat/side and upright) and tested at impact velocities of 10 m/s, 15 m/s, and 20 m/s. Nylon 12 demonstrated strain-rate dependence, characterized by changes in yield stress and changes in failure mode. At lower strain rates, the material, in both printing orientations, showed ductile budging, whereas in higher strain rates, the side printed material demonstrated a shift towards brittle failure. These failure modes were confirmed though High-Speed imaging.  Results obtained from this study provide reliable high-strain rate material data for 3D printed Nylon 12, supporting improved prediction of the structural performance of Nylon 12 components under impact loading conditions.