We present a study of the quasiequilibrium magnetization of single crystalline V3Si spheres of different pinning strength in the vicinity of Bragg glass to disordered vortex solid transition. We report a first-order-likemagnetization step below the onset of the peak effect. Its occurrence is hysteretic with respect to the direction of field scan. The step is observed only for fields oriented away from the high crystal symmetry directions [110] and [100].Accompanying the magnetization step is an abrupt reorientation of the vortex lattice towardsa crystal symmetry direction. Coupling between the vortex lattice and the underlying crystal lattice is suggested as a possible mechanism for the reorientation transition.