It helps to show us which weapon it is.
Typically, if the weapon already has spread (if it's not 100% accurate), you can go to the scripts after you see the sequences and look for a script that says "onFire" or just look for anything called "%spread" in general and edit the number that it has the equal sign with. The higher the number, the lower the accuracy.
Remember that in torque, every number or variable is labeled and organized under something (usually a script or a datablock) and you can always look at the name of it and see what it does. You probably saw "ejectionVariance" under a particleEmitter datablock. You shoot projectiles, not particles, so you should leave that alone.