Design and Fabrication of a Single-Stage Gas Gun

Designing a gas gun system which could accelerate a projectile without using explosives is a challenge. There are no design handbooks available for this purpose. As it is a multidisciplinary activity, it requires knowledge of gas dynamics, machine design, material science, production engineering, etc. Manufacturability of the components also needs to be considered during the design process. This article is a walk through the design process of a single-stage gas gun focusing on various parameters of importance. Starting with the basic construction, mechanism and principal of working are discussed in detail. The effect of various design parameters on the performance of the gas gun is assessed analytically. Starting with an almost unrealistic ideal design, an approach is made toward the real design by gradually relaxing the assumptions. The results of analysis of the final design are correlated with the performance of an actual gas gun designed and fabricated at CoE, IIT Delhi. Description of this actual gas gun is also included.