All earlier studies of proton momentum distributions in metal hydrides by DINS at Vesuvio have been performed on hydrogen-rich systems (ZrH2 etc) where the H-motion is dominated by the collective motion in the hydrogen sublattice. Here we plan to study bound proton motion at low H-concentration in the alfa-phase of Ta-hydride, where the protons are situated at tetrahedral interstices in the Ta-lattice and H-H interactions are negligible