The theoretically calculated values of deformation of a helical spring washer using the helical spring equation do not match with the practically observed values. This is due to different loading conditions in the two cases. Therefore the deflection was determined using finite element method. The actual load-deflection characteristics were obtained using a specially developed test rig. The values obtained by FEM and those obtained by actual measurement show good agreement. This approach should prove useful to designers involved in design of threaded assemblies subjected to dynamic load environment. It offers a simple and direct method of estimation of axial force provided by a helical spring washer under