Spigot test was used to assess the safety largeexplosive charges subjected to combined mechanical impact and shearing adiabaticheating. The test assembly was accelerated via a powder-driven gun design. The process of impact and ignition wasanalyzed by high-speed videosystem. Blast pressure gauges were used to measure theblast wave overpressure of explosive for characterizing the reaction extent ofexplosive assembly. The results show that no reaction takes place for TATB-based polymer bonded explosives (PBX-1) at velocity up to 37.6m/s, and HMX/TATB basedpolymer bonded explosives (PBX-2) take place deflagration at avelocity of 27.7m/s，and no reaction at velocity lessthan 25.5m/s, showing that PBX-2 were more sensitive than PBX-1 in the spigot test.