Ancient Enchanted 130mm Tank Cannon

"When we found this Cannon it was covered only in a slight surface rust without any pitting or damage. All it needed was a simple mending spell to get it back into pristine condition, not to mention the turret it was sitting in was rusted to bits. We're pretty sure it's enchanted to resist aging  with the passage of time, thus allowing it to remain in an optimal firing condition. We also kinda got it for free from some half crazed Artificer out in the boonies raving about how it's cursed cause it made him deaf..." At that the master Artificer shrugged and motioned for the Apprentice Artificer to fire the cannon.

Magic Weapon:This cannon is enchanted to give advantages against misfires and cannot be consumed by a rust monster. Once a day if you roll a Nat 1 for an attack roll, the cannon will not misfire. This cannon is Approximately 30 foot long.

Safety First:The Cannon must be attached to a base or tank turret to be fired safely. If the user attempts to hip fire the cannon all rolls to hit are made at disadvantage and the user must make a DC20 Strength save or take 6d6 bludgeoning damage, if save is made user still takes 2d6 bludgeoning damage. User must make a DC 25 Strength saving throw when attempting to hip fire or be knocked prone. If not wearing hearing protection, anyone within 30 feet of the cannon must make a DC 15 CON save or be deafened for 2D4 rounds. The only way to safely hip fire the cannon is if the Reduce spell is used on it.

Ammunition

• Enchanted Armor Piercing Charge:
  Armor Piercing Charges are magically treated to cause the highest piercing damage and destructive penetration Ancient Artificers could muster.

• Enchanted High Explosive Charge:
  High Explosive Charges are an Ancient Artificer design based on the Wizard's Fireball spell.

• Enchanted Ancient Artificer's Mastery Charge:
  Ancient Artificer's Mastery Charges are a newly designed Charge created by the Apprentice Alchemist as a final graduation test. They have been created to combine the destructive penetration and high explosive forces mastered by the Ancient Artificers.

• Enchanted Shrapnel Charge:
  Shrapnel Charges are a specialized munition utilizing a thin shell and a chamber of metal filings or ball bearings with a small explosive pack which can be fired at a target to penetrate and then expel its contents, or it can be magically timed to detonate and expel the contents prior to impact.
  

Players can craft all Charges or take found Charges to an artificer to have blueprints made. Shrapnel Charges are roughly 150 GP per Charge, Armor Piercing Charges are roughly 200 GP per Charge, High Explosive Charges are roughly 300 GP per Charge, and Ancient Artificer's Mastery Charges are roughly 450 GP per Charge if purchased at an artificer's shop. An artificer not currently furnished with a blueprint cannot make a Charge unless they have made one prior. If repeating shot is applied to this cannon it will fire whatever Charge variant was fired through it last.

If you want to find these Charge types in the homebrew magic item listings, look to the comments below. Each Charge has been attributed to an "Arrow" as to track it in player inventories.

Firearms are a new and volatile technology, and as such bring their own unique set of weapon properties. Some properties are followed by a number, and this number signifies an element of that property (outlined below). These properties replace the optional ones presented in the Dungeon Master’s Guide. Firearms are ranged weapons.

Reload. The weapon can be fired a number of times equal to its Reload score before you must spend 1 attack or 1 action to reload. You must have one free hand to reload a firearm.

Misfire. Whenever you make an attack roll with a firearm, and the dice roll is equal to or lower than the weapon’s Misfire score, the weapon misfires. The attack misses, and the weapon cannot be used again until you spend an action to try and repair it. To repair your firearm, you must make a successful Tinker’s Tools check (DC equal to 8 + misfire score). If your check fails, the weapon is broken and must be mended out of combat at a quarter of the cost of the firearm. Creatures who use a firearm without being proficient increase the weapon’s misfire score by 1.

Explosive. Upon a hit, everything within 5 ft of the target must make a Dexterity saving throw (DC equal to 8 + your proficiency bonus + your Dexterity modifier) or suffer 1d8 fire damage. If the weapon misses, the ammunition fails to detonate, or bounces away harmlessly before doing so.

Ammunition

All firearms require ammunition to make an attack, and due to their rare nature, ammunition may be near impossible to find or purchase. However, if materials are gathered, you can craft ammunition yourself using your Tinker’s Tools at half the cost. Each firearm uses its own unique ammunition and is generally sold or crafted in batches listed below next to the price.

THIS IS UNOFFICIAL MATERIAL

These game mechanics are usable in your campaign if your DM allows them but not refined by final game design and editing. They aren’t officially part of the Dungeons & Dragons game and aren’t permitted in D&D Adventurers League events unless otherwise stated.

Notes: Damage: Force, Cannon is roughly 30 ft long and dimension of shell is 130 mm x 845 mm., Damage, Combat, Two-Handed, Reload, Misfire