The results of reactor physics calculations for the currentiy proposed MSRE core design were compiled. The core was assumed to consist of a homogeneous mixture of fuel salt and graphite, with 22.5% of the core volume occupied by fuel; the salt composition was the currently proposed mixture of 70 mole% LiF, 23 mole % BeF/sub 2/, 5 mole% ZrF/sub 4/, 1 mole% ThF/sub 4/, and UF/sub 4/ as required for criticality. The calculated critical mole%, assuming 93.5% U/sup 235/, was 0.2 mole% UF/sub 4/; the associated inventory of U/sup 235/ in the circulating system was 45 kilograms. Mean core thermal flux was estimated to be 2.9 x 10/sup 13/ n/cm/sup 2/ sec with an associated mean power density of 3.9 watts/cm/sup 3/ for 10 megawatts total reactor power. (auth)