Suppressing Fire is a perk in Wasteland 3.
They wanted to hide inside their vehicle. It's only fair you give 'em a hot box.
Suppressing Fire (5 AP): A Heavy MG attack that consumes twice as many bullets. Enemies in the area take minor damage and are Suppressed, losing -0.8 Combat Speed and -20% Hit Chance for 2 turns. Deals +300% damage vs. Demoralized targets.
Damage: 100% of weapon damage.
It's best to use this ability with a HMG that consumes 9 rounds per Attack
Damage and ammunition cost
The ability's description is factually incorrect; the ability ALWAYS uses 18 rounds, no matter how many rounds the HMG you've equipped consumes in a standard Attack. The ability's damage is also based on a single round of the HMG. As round damage for HMGs is partially balanced around the number of rounds consumed per Attack, weapons like the Hoser can deal a lot more damage with Suppressing Fire than the Minigun. However, Using Suppressing Fire with the Hoser results in 4 & 1/2 Attack's worth of rounds being consumed, which can be awkward for reloading and burn through its magazine fast.