Aiming at the stuck problem of a vehicle-mounted howitzer with conveying machine,we analyzed the causes of sticking and propose solutions. By analyzing the failure tree, decompressing and rechecking the size of the relevant parts, size-chain calculation and other means, the cause of the problem was accurately located, the reasons of conveyor installation clearance and positioning of the ammunition chain was swings from side to side during the ammunition loading process. When the conveyor was installed with the maximum clearance of 2 mm, and the limit plate was installed, the stuck problem of ammunition conveyor had been solved. The results show that it was aiming to make changes to process and technical documents, curing the technical state, it is also extended to other similarly equipped conveyors.