Modern Firearms Use

Simple Ranged Weapons Proficiency. Pistols, revolvers, shotguns and single shot rifles are simple ranged weapons.

Martial Ranged Weapons Proficiency. Machine guns, rocket launchers and grenade launchers are martial ranged weapons. If you aren't proficient in a martial ranged weapon you attack with, with you suffer disadvantage to the attack roll.

Single Shot. The most basic form of attack with a firearm is a single shot. One attack is one pull of the trigger and fires 1 bullet at one target. A successful attack deals the weapons damage.

Burst Fire. A burst fire attack can only be used by someone that is proficieny with the weapon. You gain a +3 to hit when firing burst fire. A burst fire fires 3 bullets and deals the weapons normal damage.

Autofire. If a ranged weapon has an automatic rate of fire, a character may set it on autofire, some heavier weapons only have autofire mode. Autofire affects an area and everyone in it, not a specific creature. The character targets a 10-foot-by-10-foot area; make an attack roll, each target in the area must pass a Dexterity save vs your attack roll or take the weapon's damage. Autofire shoots 10 bullets and can only be used if the weapon has 10 bullets in it.

Pin Down. Pin Down affects a 10-foot-by-10-foot area and everyone in it, not a specific creature. As an action that starts on your turn you fire single rounds routinely in a 10-foot-by-10-foot area; make an attack roll, any creature that starts their turn in the area, or any creature that enters the area before the start of your next turn must pass a Dexterity save vs your attack roll or take the weapon's damage. Pin Down shoots 10 bullets and can only be used if the weapon has 10 bullets in it.