The unique capability of the new version of the McChasy code (called McChasy2) is to provide the possibility to simulate experimental energy spectra delivered by Rutherford Backscattering Spectrometry in channeling direction (RBS/C) using large atomic structures (ca. 10⁸ atoms). Ni-based alloys are nowadays one of the most studied and promising materials that can be used in the power generation sector and in general for high-temperature applications because of their radiation resistance and proof against harsh environmental conditions. In this work, we present recent results of investigations regarding simulations of extended structural defects (edge dislocations and loops) developed in the directions typically observed in the fcc systems that are formed inside nickel-based single-crystal alloys. The extended defect models are created using ATOMSK and the Molecular Dynamics (MD)-LAMMPS thermalization process. The models are then used to create virtual samples and fit experimental RBS/C spectra.