No, she is talking about the Inertia-control-based mass-accelerator(while railgun is electric-magnetic-based mass-accelerator) in Cannon God Exaxxion
The rifling further adds velocity electromagnetically, similar to a rail gun.The muzzle velocity, effective range, accuracy and damage potential are all greatly enhanced.Haa~It starts off with chemical propulsion... that is to say, the same method as gunpowder.*munch-munch-munch*A cannon appears in the story......are you giving out, Homu Homu!What information...