Aiming at the problems of traditional shoulder-fired weapon in shooting moving targets, such as complex operation process, large influence of shooter on loading accuracy, low strike efficiency and low hit accuracy, a simple fire control automatic loading scheme for moving targets based on strapdown inertial navigation moving base alignment principle is proposed. A simple fire control operation process is designed, and the accuracy of the meter is tested through three working conditions, such as the prototype turntable and the actual combat operation. The results show that the scheme can greatly simplify the operation process of shoulder-fired barrel weapon to attack moving targets and improve the attack efficiency under the condition of meeting the loading accuracy, which has a certain reference value.