The one man army, an unstoppable snap shot, shooting wildly into the fray trying to take as may people down as fast as possible.

At 3rd level, you gain a +1 bonus to attack rolls you make with ranged weapons.

When you reach 7th level, your speed when handling your guns improves.
You add your proficiency bonus to your initiative. You can stow one firearm and draw another firearm as part of the same object interaction on your turn.

At 10th level, you learn to handle yourself in close combat.
When you make a firearm attack while a hostile creature is within 5 feet of you, you don't have disadvantage on the attack roll.

In addition, if you hit a creature within 5 feet of you with a firearm attack on your turn, that creature can’t take reactions until the start of your next turn.

Starting at 15th level, you learn to trade accuracy for fanning your weapon.
If you have advantage on a firearm attack against a target on your turn, you can forgo that advantage to immediately make an additional firearm attack against the same target as a bonus action.

Starting at 18th level, you are ever ready to spring into action.
If you take the Attack action on your first turn of a combat, you can make one additional firearm attack as part of that action.