The Hydrogen Intensity Real-time Analysis eXperiment (HIRAX) is a 21cm intensity mapping experiment to be deployed in South Africa. It will consist of 1024 six meter parabolic dishes, and will map much of the southern sky over the course of four years. HIRAX will look near when the universe shifted from matter to energy dominated, a redshift range that is relatively unexplored; it will provide a new probe to better understand BAOs, at different redshifts and with different tracers than prior optical surveys; and it will dramatically expand the detection and understanding of fast radio bursts (FRBs). For HIRAX to achieve its bold science goals, it will need to overcome bright foregrounds, which requires precise characterization of the instrument. My talk will focus on two aspects of the HIRAX instrument characterization: (1) optimizing the signal/noise of feeds by developing a test chamber, and (2) mapping the antenna beam patterns. For the first, I will discuss the design for a cryogenic test chamber to take y-factor measurements and precisely measure antenna noise temperature. For the second, I will touch on precision tests and preliminary beam maps we’ve completed as well as our path to mapping the full array. Both projects are critical to HIRAX’s development, informing final feed design and generating the beam maps that will factor into all cosmological analysis.