Spring or gas firing mechanism? Each types do the job by way of a piston that compresses air then releases it with every cause squeeze. The differences will be the types of compressors that they use to power the piston. Spring-powered guns have a spring system in position, when gas-powered https://guns-for-sale-in-sports-a06283.wikitelevisions.com/7529199/considerations_to_know_about_handgun_nerf