Borosilicate glasses are suitable materials for the immobilization of high-level nuclear waste. One of the main questions is the structural changes of B-O network. We perform mass-resolved neutron spectroscopy on the SiO2-B2O3-Na2O system and additionally on the SiO2-Na2O sample serving as a standard for comparison of the NCS response. By measuring the nuclear momentum distributions of O and B nuclei in ternary series of experiments with increasing concentration of B2O3 one can trace the changes to gM(v) and characterize the local effective potentials felt by B, O nuclei due to the increasing disordered character of the lattice and changing coordination of B atoms. The proposed experiment will extend the benchmarking capabilities of the NCS technique to the realm of disordered systems by allowing testing structural predictions based on RMC modelling.