Weapon Assembler

Weapon Assembler is a block. Builds guns. Put a barrel, a frame, an action and a trigger group in its four slots and the gun appears. All four parts have to be for the same gun; each part's tooltip says what it fits.

Crafting

Made at Crafting table
Steel PlatePistonSteel PlateIron GearAnvilIron GearSteel PlateBlast FurnaceSteel Plate
Weapon Assembler