Everything here will be Homebrew. But it will either be a work in progress, or just adds some nice shiny new toys.
First things first. These weapons are new to Spelljammer, some are down right Gnomish made. But in the end a generous and enthusiastic (not including rich) Mercant Queen has brought forth these to the cosmos!
Swivel Bombard: cost 15000 gp. Damage 1d4 Hull Points, 2d6 Hit Points, crew 1-2 (trained/cracked crew have no problem with this gun, where as greens struggle with new weaponry.) RoF: 1/2. Crit: 19-20 Range: 1 hexes. It is considered a light weapon, that can easily be replaced/remounted/carried. They weigh about 50 lbs and take up about 5 feet of space (with crew) it was designed by gnomes, who, at the will of their captain, designed something that is cheap for beginning merchants, but in numbers are useful for military purposes.
Thunder Gun/Static Canon: Work in progress. A heavily modified Fire Thrower, it has a crank on the side or on top of the gun itself, when cranked it builds up enough static electricity to shoot a lightning bolt. Gnomes designed this. 6d6 Hit Points (every 10 does 1 hull) Range: 2 hexes. RoF: 1/4, Crew 2
Portable Greek Fire Thrower: Work in progress. A smaller more portable version of the Fire Thrower. You carry a backpack that holds 6 shots or charges. To fire you must pump up the tank to build pressure and then simply pull the trigger. A bayonet has been installed in the front, so while the weapons cools you can still attack (1d4 for bayonet) 1d12+fire damage, RoF: 1/2 to cool the weapon. If fired before cooled, 45% chance of setting off the next charge as a critical failure. Crit fail 1-2, Crit success 18-20. Designed by gnomes.
DEVICES "Instrument of the Berserker:" this beauty is used mainly for small boarding ship's like the Cookie Cutter. The helmsman rams a ship, plays an instrument with this enchantment, and opens the doors/cone ram and releases hell upon thy enemies! (In theory it's supposed to have crew kill more bad guys, but they're in a rage, sooo... DMs discretion advised)
"Flame Retardant Suit:" Acts as Ring of Fire Immunity and has AC of studded Leather. Has a mask that allows you a +1 to save vs. poison. Cost 15000. Gnomish Designed.
AMMUNITION "Grapeshot:" Coins, silverware, metal balls and pellets. It doesn't matter what you use, it still kills crew nicely. From 2d10 with misc items, 3d10 with stone shot, 4d10 with metal. Does 1 point of Hull to every 10 Dam to ship's 10 tons and smaller.
"Heavy shot:" Not only is this Iron shot (still gets the bonuses) it does 2d6 hull damage but requires twice the amount of of smoke powder
Meglahammerdon: 120 tons 120HP Min Crew: 1 Max Crew: 120 AR 2 MC B SR +3 to pilot. 12 Protected Turrets (10 are +1 bombards, 2 are +2 Dual Ballistas) (Braid Blue teeth is a LvL 6 Asamer Fighter who has +2 Cutlass, Rapier (She is a master with both and dual wields) and a +1 wheel lock and breastplate. Alignment: Questionably Chaotic Neutral. Her main focus is charisma(18) so she's always willing to talk, usually for a price, and is always to the point. She has issues with most bird races such as the Dowar and aaracokraa)
There is only one in existence, designed by the Arcane, it belongs to Merchant Queen Braid Blueteeth, famous for killing her step father and notorious pirate Butterball Blueteeth, a bloodthirsty trader, and bounty hunter. When this ship pulls up to Port, it is best to make room, not only is it twice the size of a normal Hammership, but the ship makes everyone feel uneasy. Besides being a powerhouse of magical bombards and dual ballistas, the ship is covered in dragon skin and skulls ranging from dragons to beholders and mindflayers. If one were to cast "detect magic" almost the entire ship glows. Even the paint. The captain is ruthless in combat and very unpredictable, and is said to love gold more than anything. It is said she almost bombarded a planets capital city because a merchant cheated her of 4000 gold, but that is not to say she doesn't care for her crew. She's only been sold out once. Those traitors were forever marked with her sigil of a skull with blueteeth and a squid/dragon hybrid.
Cookie Cutter Shark: Work in progress. 5 ton ship. Was meant to be a stealthy boarding ship. It's "ram" is similar to the cone ram, except it was to cut a hole in the sides or bottoms of ship's and send in anything from thieves and assassin's to berserkers and privateers. Currently trying to implement "chameleon" spell
Tiger Shark: Work in progress. 10 ton fighter ship armed with 4 Swivels and a blunt Ram. There is work on a heavy variation of 20 tons and better armor.