A method for calibrating a nuclear gauge of the having a source includes providing a nuclear gauge comprising a radiation source, the radiation source being coupled with a computing system with a machine readable program stored thereon containing a calibration routine. An operator places the gauge on one or more specified blocks to adjust the source within each block to one or more specified positions to initiate a count. The method includes determining that the source is at each position before each count begins, adjusting the counting times before each count begins by the program on the nuclear gauge based on each position of the source to obtain calibration information, obtaining counts at each position, storing the counts within the computing system of the nuclear gauge, and calculating for each position calibration coefficients.