One type of gamma-ray detector is the HPGe detector, which is used to measure poor performance in soil or ambient radioactive samples due to its very high resolution and relatively good efficiency. Determining the activity of ambient samples requires prior knowledge of the efficiency of the full energy peak under the measurement conditions, and it is necessary that the detector efficiency in the considerable range of gamma energy required by standard homogeneous sources and All shapes (with similar dimensions, density and chemical compositions) are determined with ambient samples at different gamma ray energies. These conditions are not easy to achieve in many laboratories. Therefore, in recent years, attempts have been made to simulate the efficiency of this type of detector and replace the experimental method. However, before using simulation calculations, it is necessary to confirm the correctness of this type of calculation by comparing the experimental results and making the necessary corrections. In this regard, in this dissertation, the whole system of bulk standard spring mass detection system was calculated using MCNPX.2.6 code, simulation and detection efficiency of this system in the range of energy (121 to 1408 kV) and compared with experimental results. Then, by using simulations and measurements related to point springs and using the efficiency transfer function, the simulation results of bulk springs are corrected to be closer to the experimental results. Using the efficiency transfer function reduced this difference to less than 5%, which would be very satisfactory for measuring environmental samples. In the following, by calculating the experimental efficiency and simulating a point spring at distances of 15, 25 and 35 cm from the detector, we will show the efficiency of a massive spring simulation using the efficiency transfer function. This function is dependent only on the photon energy and is largely independent of the geometric configurations.