A hollow cylinder has an electromagnet to hold back a canister and either an induction heating linear actuator or a firing pin to ignite the primer-containing combustive material inside the canister to eject a locked piston from the cylinder. There is a motor-included turbogenerator around the cylinder, which converts the energy of the post-combustion gases into electricity to get stored and to power an integrated or separate annular stator assembly to give the ejected piston a rotatory motion for stability in projectile motion. Another device has a helically arranged, multi-pole permanent magnet assembly annularly integrated around the cylinder to give the ejected piston a rotatory motion for stability in projectile motion. In other forms, an annular stator assembly around the cylinder is supplied with switched, externally generated electric power without either a turbogenerator or the motor-included turbogenerator to respectively produce electricity or to provide gyroscopic stability to the cylinder.