Differential cross sections for coherent scattering of 145.4 and 279.2 keV gamma rays were measured for Cu, Mo, Ag, Cd, Sn, Pr, Sm, Gd, Dy, Ho, Yb, Ta, W, Pb, Th and U employing a reflection geometry set-up with a graded shielding arrangement. A 133 cm3 HPGe detector was used to detect the scattered gamma rays. The measured cross sections were compared with the experimental values in literature and with the numerically calculated results using S-matrix theory for available cases. From the measured cross sections the form factors corresponding to 8.295 and 15.923 AA-1 photon momentum transfer were extracted. The results are discussed in the light of the predictions of form factor formalisms.