Hmm, assuming you’re using projectiles to represent your bullets, maybe spawn a particle system attached to your projectile? Perhaps a ribbon emitter or a beam emitter with start point being your weapon and the end point bound to the projectile… Just some ideas based on the Cascade tutorials that I’ve myself been browsing today.
Hopefully others can chip in as well, I recall seeing a projectile weapon thread using curvy bullet trails accounting for the projectile falling down due to drag, etc (those were debug lines though as far as I remember).