<p dir="ltr">Reaction zone thickness directly affects detonation properties such as detonation velocity and critical diameter. It is hypothesized that the effective reaction zone thickness is influenced by the particle size distribution and solids loading (wt.%) (solids loading) of an explosive material. In this study, we test several paste extrudable explosive (PEX) samples, to study the effects that varying particle size distribution and solids loading have on detonation properties. The PEX samples are based on four different explosives (RDX, PETN, HMX and DAAF), created by suspending explosive particles of different size distributions within an inert binder. A novel half- cone geometry is used to test the samples allowing for the capture of detonation speed (using a high-speed camera) and failure thickness data, by using the polycarbonate half-cone as a witness plate. Using this data, we create a diameter effect curve for each of the samples, allowing us to indirectly compare relative reaction zone thicknesses by measuring the slope of the linear region of the plots. Data found in open literature was compared to the PEX samples used in this study, but data was scarce. This study hopes to narrow the gap found in open literature.</p>