A statistical analysis of collision cascades caused by 1000 randomly directed energetic primary knock-on atoms (PKAs) using molecular dynamics (MD) simulations in crystal Fe(90%)Cr(10%) is presented. An Fe atom is chosen as the PKA in the energy range 0.1 to 5 keV. The standard deviation of the number of Frenkel pairs created during the collision cascade and range of the PKAs is presented. It is shown that the PKAs must be launched in ∼100 randomly chosen directions for the standard deviation to reach a steady value. For PKA energies 1 keV, 35 of secondary recoils have greater displacement than the PKAs. The results from the MD simulations for the number of displaced atoms are compared with those from the Norgett, Robinson, and Torrens model and other MD simulations of cascade damage in FeCr alloys.