Closest I could come with an answer to that would an old Brown Bess Musket. Fill it with powder and add whatever is handy for a load.
wrought iron is a term used for cold iron which is plain iron that has not been combined with other elements its also known as elemental iron.I'm guessing the wrought iron is key to plot/storyline as a needed element for the ammo within the books "universe". If iron alone was sufficient for terminating whatever fictitious critter, them mild steel jacketed ammo already exists. Many former Eastern block countries use rounds with these jackets as part of the projectile.
I love science fiction, fan fiction novels. One thing you can do without violating laws or messing up barrels is to use a magnetic rail gun to fire the steel or cast iron projectiles. It is possible to build one from items found at hardware stores or junkyards.I'm a writer of fanfiction and not familiar with firearms. I was wondering what kind of handheld firearm could fire wrought iron rounds. Any help would be greatly appreciated!