MAX phases such as Ti3SiC2 have an exciting combination of properties however no single crystals are available to enable measurement of their intrinsic (single crystal - SC) values. This has caused reliance upon theoretical values. Ab initio structure and property calculations for a great many MAX phases have been published including >250 elasticity tensors. We have developed a method to measure the SC elastic constants from polycrystals and our initial results (RB 810407) are at odds with published ab initio work. Here we aim to use in situ strains recorded using ENGIN-X to determine the SC elastic constants for 5 more MAX phases. This information will enable is to test the veracity of published ab initio calculations. The results will also be valuable in modifying procedures for the ab initio calculation of elastic constants to bring them into closer agreement with experiment.