The aim of this paper is to evaluate the perforation effectiveness of projectiles generated by Inhibited Shaped Charge Launcher (ISCL) and aluminum spheres on typical spacecraft Meteoroids and Debris Protection Systems, through the use of numerical simulations. In the first part of the work a suitable model for shaped charge projectiles was determined, by simulating ISCL impact tests performed at Battelle Ingenieurtechnik GmbH on aluminum Whipple and double bumper targets, and at Southwest Research Institute on the Columbus Advanced Shields (AS). The best agreement with experiments was found by modeling the shaped charge projectile with a conical external shape, no internal cavity and no shear strength. The model was then used to determine the ballistic limit of the Columbus AS at 11 km/s (the typical velocity around which shaped charge projectiles are launched) and at 6.5 km/s, that is the maximum velocity at which the Columbus AS ballistic limit has been experimentally determined for aluminium spheres. In this analysis the projectile external geometry was considered to be cylindrical, in order to univocally scale the mass for a fixed value of the ratio between the length and the diameter, and also allowing a comparison with previous studies in which shaped charge projectiles were considered as cylindrical. The results were compared with the ballistic limit predicted by simulation of aluminum spheres impact, in order to calculate the ratio between the critical mass of a spherical and a shaped charge projectile (Ballistic Limit Mass Ratio). The obtained values compared quite well with the data available from the open literature. All simulations are performed with the AUTODYN-2D hydrocode in axial symmetry, thus limiting the analysis to normal impacts.