The dynamic buckling response of a cylindrical shell under axial impact is considered in this study. Specifically, the effects of various combinations of mass and velocity on the response of the cylinder for constant (near critical) momentum. A rigid mass is affixed at one end of the cylinder and is impacted at the other end against an infinitely rigid wall. The boundary conditions are defined by considering the mass rigidly attached to one end, axial velocity towards the right wall, and simply supported contact interface conditions. An explicit finite element code is used (LS-DYNA3D), to determine the response of the shell as variations of mass and velocity are made for a given (near critical) momentum. Specifically, in the neighborhood of critical impact velocities.