The arcane gunslinger

Gunsmith

At 2nd level, You gain proficiency with all firearms and can repair/create them whenever the DM allows it. (If you have the needed parts)

Infuse Magic

Also at 2nd level, You gain the ability to cast specific leveled spells (Of which you have) onto your firearms. The spell must be either a cantrip or a level 1 spell. This Feature ends after 12 hours of the spell being infused. During a short rest, you can expend a hit die to change the spell. This feature resets upon the completion of a long rest.

At Higher Levels. Whenever you gain a new spell slot higher, you must wait 1 more level to infuse it into your guns. At 10th level, you can infuse 2 spells at the same time.

Aim of The Mage

Starting at 6th level, you can use a spell slot to gain advantage on a firearm attack roll. Additionally, whenever you get a critical hit with a firearm attack, you can use a bonus action to make a spell attack.

Magical Gun-nut

At 10th level, whenever you misfire (get a natural on a firearm attack roll) you can roll a Intelligence saving throw make the gun UN-misfire. In a successful save, you regain a spell slot of levels for or lower.

Deadshot Magic

At 14th level, You can add spell slots of levels 4th or Higher to add to your firearm attack roll.