Brownmillerites of the form ABO2.5 constitute an interesting variant of oxygen deficient perovskites, with magnetic ions stabilized in alternate octahedral and tetrahedral environments. Interesting from both the magnetic and electronic points of view, these systems are only now being investigated in right earnest. Here, we propose measurements of elastic and inelastic neutron diffraction on the brownmillerite BaCoO2.6, with the aim of uncovering the evolution of magnetic structure as well as the constituent magnetic interactions.