In this work, we examine the available experimental and theoretical data of scattering cross-sections for fast incoming particles on a many-body target. We found that use of the Born approximation and the Hartree model together with the Thomas–Fermi model gives a general rule that describes the increasing dominance of elastic scattering processes for targets with an increasing amount of particles. Here, significant correlation is found for targets with similar electron configurations, while a deviation is observed with increasing molecular complexity. Furthermore, we discuss the limitations of this rule concerning its divergence for large molecules and condensed matter.