A small quantity of flammable gas mixed with dust can cause a large explosion with severe consequences. In this study, hybrid mixtures explosion tests were performed in constant volume 0.02 m3 and 1 m3 spherical vessels. Fifty pressure-time curves were recorded. The effects of ignition source and test vessel volume on burning velocity were investigated for Lycopodium Clavatum-methane-air hybrid mixtures. The most important results from evaluated experiments are the values of burning rates to understand better the fundamental flame propagation process in hybrid mixtures and the impact of volume and ignition source on combustion regimes.