The ultimate toolbox for creating guns in Minecraft.

Flan's Mod: Reloaded is like a library mod, but way cooler.

Flan's Mod: Reloaded loads from Content Packs you can find here on CurseForge, turning simple JSON files, sounds and textures into a lethal upgrade for your world.
This is the official continuation of Flan's Mod, rewritten from the ground up for a new era of Minecraft.

Currently, Flan's Mod: Reloaded has the following support:

Guns and similar tools (binoculars are scoped guns that don't shoot)
Magazines for your guns
Bullets for your magazines
Attachments (barrels, scopes, grips and stocks to modify your guns)
Parts (components to combine to craft everything else in the mod)
Npcs (think wandering traders with a bit more life to them, and a lot more ammunition)
Workbenches (this includes all crafting and gun modifying required for the mod)

Some things you may recall from Flan's Mod 1.12.2 that are not in yet, but coming soon:

Vehicles (all planes, tanks, mechas etc combined into one multifunctional type with all the best bits of each)
Armour
Teams, loadouts, multiplayer gamemodes

One massive upgrade from Flan's Mod 1.12.2 is the completely rewritten Content Pack creation pipeline.

Details and tutorials will be available soon, but in the meantime you can try out a beta version of the Content Tool over on GitHub

Using the Unity Editor environment for content management, you can import old 1.12.2 packs into the Editor, tweak assets in the Unity Inspectors and export directly to a new Flan's Mod: Reloaded format content pack.

As a result of large scale refactoring and a new content system, 1.12.2 and earlier packs do not work in Flan's Mod: Reloaded without being processed by the pack creator or license holder with the new tool.

Make sure you install some content packs as well, Flan's Mod has no default content.
You can also create your own packs. Check out the Flan's Mod Discord for more info coming soon.