Conceptual Molten Salt Breeder Reactor (MSBR) is under development in BARC with longterm objective of utilizing abundant thorium available in India. It is based on molten salts, which acts as fuel, blanket and coolant for the reactor. LiF-ThF4 (77.6-22.4 % mole) is proposed as a blanket salt for Indian MSBR. A laboratory scale molten salt natural circulation loop named, Molten Active Fluoride salt Loop (MAFL) has been setup for thermal-hydraulic, material compatibility and chemistry control studies. Various steady states and transient experiments have been performed in the operating temperature range of 600oC to 750oC. The loop operates in the power range of 250 W to 550 W. Steady state correlation given for natural circulation flow in a loop is compared with the steady state experimental data. The Reynolds number was found to in the range of 57 to 114. CFD simulation has also been performed for the same using OpenFOAM code and the results are compared with the experimental data generated in the loop. It has been found that the predictions of OpenFOAM are in good agreement with the experimental data. In this paper, features of the loop, its construction, the experimental and theoretical studies performed are discussed in detail.