Low temperature nuclear orientation (LTNO) is applied to thermal neutron irradiated single crystal ( 160 Tb)TbNiAl 4 . The magnetic field dependence of the gamma ray anisotropy is recorded and a temporary reduction is seen only during the transit of the first TbNiAl 4 metamagnetic transition at ∼7 T, indicating the changed magnetic structure of the higher field phase still has essentially a axis moment alignment. A similar behaviour is seen for ( 147 Nd)NdNiAl 4 .