Not necessary, getting lots of smoke on the shot has been done plenty of times.
It's simple, the gun needs to fire an AEmitter and then the emitter spawns all the particles (the smoke and the bullet).
Check the Coalition's Revolver Cannon code, it works like that because this method is also great for reducing the kickback made by heavy projectiles.
Also, I made this question some time ago,
check this thread, it helped me much.