Automatic Weapons - Guns firing more than one shot per pull of the trigger can be used in three primary ways.
Burst - The attacker fires three bullets using one attack roll against a single target. Burst fire counts as one action, but cannot be done more than twice in one turn. A burst can be aimed at a general body area, but not to a specific target. Roll damage for one hit, then multiply penetrating damage by x2. This is a simple way to reflect multiple rounds impacting in roughly the same area.
Autofire - The attacker uses 10, 20, or more rounds against a single target, in multiples of ten, to a maximum of forty rounds. The increased odds of hitting the target with a round are counteracted by the recoil and dispersal of rounds, roughly balancing out bonuses or penalties. Autofire is an action, but no other attack action is possible, before or after the autofire. Autofire cannot be a called shot. Roll damage for one hit, then multiply penetrating damage by x3; do this separately every 10 rounds in the burst. This is a simple way to reflect multiple rounds impacting in roughly the same area.
Spray Fire - The attacker uses 10, 20, or more rounds against a single target, in multiples of ten, to a maximum of forty rounds, against an area 5' to 10' wide. Because the target is an area and not an individual, cover and hit location modifiers do not affect the attacker's roll. As long as the attack makes a minimum of (3), all targets in the area must make a defense roll. Cover modifiers are treated as bonuses for the defenders. Roll damage for one hit, then multiply penetrating damage by x2. This is a simple way to reflect multiple rounds impacting in roughly the same area. Spray fire is primarily used for "suppressive fire". Any NPC's under such spray fire must roll above the attacker's roll in order to do anything but evasion and seeking cover.
Stun Weapons - Some weapons do STUN damage, such as tasers, shockrods, beanbag rounds, and so forth. These weapons will force a Vitality + Willpower roll vs. a difficulty rating, depending on the specific weapon. A typical one will be “hard=11’ or Formidable=15” for particularly potent stunners.