Lead Mage

Lead mages are artificers who enhance their magical abilities with the use of firearms, be it a regular pistol or a cannon. These "magicians" are extremely rare, due to limited knowledge and lack of gunpowder in most places, and therefore they learned to combine magic and steel to obtain personal semi magical weapons.

Gun magic (3lvl)

You have given yourself completely to your weapon. 

You are proficient in all types of firearms.

You can now use any firearm as a spell focus.

All spells that target arrows/crossbow bolts/quivers now can also target ammo.

Mana bullets (3lvl)

As an action, you can use one of your spell slots to create 10 lead bullets in your empty hand, these are suitable for the one-handed firearm you are holding in your off-hand. Bullets last for 24 hours and disappear after that time.

These bullets deal magic damage.

Smart bullets (5lvl)

Your bullets now have a piece of consciousness that allows them to adjust their flight trajectory. 

When you shoot, you can use your reaction to give your shot attack advantage, and your shot also ignores cover by half and three quarters. Such a shot is considered critical on a roll of 19-20 on d20. You can use this ability a number of times equal to your Intelligence modifier. This ability is restored after a long rest.

Magic infused bullets (9lvl)

Your spells and your wearpon become one.

When you fire a firearm, you can spend one spell slot to make your bullets have one of the following effects until the end of the turn:

Fire fusion - Your bullets deal an additional 1d6 fire damage, on a hit the target must make a dexterity saving throw (your spell dc), on a failure it ignites and takes 3d4 fire damage at the start of each of its turns. The target can use an action to put out the fire, or someone else must spend an action to put out the fire.

Ice Fusion - Your bullets deal an additional 1d6 cold damage, on a hit the target must make a Constitution saving throw or suffer frostbite. While the target is frostbitten, it has disadvantage on attack rolls and strength and dexterity saving throws. On each of the target's turns, the target can repeat the Constitution saving throw to end the effect. The effect also ends if the target takes fire damage.

Psychic Fusion - Your bullets deal an additional 1d6 psychic damage, on a hit the target must make an wisdom saving throw, on a failed save the target becomes charmed or frightened by you for a minute (you choose the condition). At the end of each of its turns, the target can repeat the saving throw to end the condition. While this condition is affecting a target, you can use a bonus action to command it to move in a specific horizontal direction; on the target's turn, it will perform this movement, but can still use its actions

Windy Fusion - Your bullets deal an additional 1d6 magical piercing damage. If the bullet hits a creature, you can make another attack roll within 20 feet of the target, dealing normal damage on hit and allowing that bounce to be repeated. (The bullet cannot bounce back at a creature that has already been hit by the shot)

True Lead Potential (15lvl)

As an action once per long rest for a minute, you can enter a state of True Lead Potential. In this state, your understanding of any firearm reaches its maximum. You gain +2 to hit and damage rolls with firearms and, depending on the weapon type, gain an ability that you can use once during this condition (no action required). Also when you fire your wearpon it don't need any ammo.

Pistol - Your next attack with this weapon releases an explosive ball in the pistol's attack radius that explodes everything within 10 feet, everyone within that radius must make a dexterity saving throw (your spell dc) dealing 8d6 fire damage to anyone who fails the save and half on a successful one.

Rifle - Your next shot deals double damage on a hit, and triples the damage at the end on a critical hit. Also if you can see the target but it behind the full cover you can still attack that creature.

Shotgun - The next time this weapon is fired, a twenty-foot cone of fire comes out of the muzzle and anyone within that radius must make a Constitution saving throw, taking 8d6 fire damage on a failed save, or only half on a successful one.

Two firearms - with two consecutive shots, you can re-fire two more shots from each weapon at any target in the weapon's attack zone if you can see the target