Understanding fractures creating process during the dynamic indentation of a spherical carbide insert is a key factor to optimize the operation of a percussive drilling system and improve penetration rates and tool life while drilling in hard, abrasive rock formations. This study presents experimental results of dynamic indentation tests with combined action of an impulsive load and a static load of a bit using a single spherical carbide insert on five types of rocks. A dedicated and innovative experimental setup using a gas-gun drop test was developed to reproduce the loading forces and mechanical characteristics of a Down-the-Hole (DTH) hammer drill. A highspeed camera was used to visually determine when the major fractures, such as radial and side cracks, coalesced to create large fragments and to determine the bit displacement curve during the whole indentation process by tracking the end of the bit. To characterize the damage in the rocks, the mass of the fragments was weighed, and the Specific Energy (SE) was calculated. Experimental results showed a strong correlation between the major changes in the slope of the stress signals recorded in the drill bit and the major fragmentation events recorded with the high-speed camera. In the granites, large fragments typically associated to side cracks were generated during the loading phase. In contrast, in the limestone and the sandstone, the fragments were generated during the unloading phase. Finally, it was found that in granites, the earlier the side cracks occur relative to the maximum indentation time, the lower the efficiency of the indentation.