This is the skill of flamers, miniguns, rocket launchers and other large support weapons. If it's a large weapon, you can count on Big Guns being the skill rolled against. Like Small Guns, the better your skill, the easier it will be to hit your target, and the longer range you can really hit people at.

Initial Level: Starting Big Guns skill is equal to 10% + (1% x Agility). Average characters have a 15% skill.