In the action game The Last of Us: Part 2 (TLOU2), you can find 12 types of weapons/firearms, and this guide shows all their locations. Most weapons will be found through the story, while some can be found in the game world. If you miss them on the first appearance, they will reappear in new locations until you get them through the story. You can also upgrade weapons at the workbench.
For finding all types of weapons, you will receive the High Caliber achievement.
Location: Starting weapon, will automatically appear in the inventory.
Location: Can be obtained during Chapter 4: Patrol. In the middle of the chapter, when you find the animal carcass.
Location: Can be obtained during Chapter 7: Packing Up. Found in a box that you must open, impossible to miss.
Location: Can be obtained in Chapter 9: Downtown. The weapon is inside the bank vault. The bank is located in the ruins on the left side of the Seattle area. When you look at the map, it is the third block from the left in the bottom row. The code for the bank vault is 60-23-06.
Location: Can be obtained in Chapter 16: Hillcrest. Upon seeing black smoke from afar, you will enter a building and check the garage (story path). Here you will find a new type of infected enemy. Kill it and inspect its body to get the Bow. Right after you open the garage door, you will see several archery targets. Even after this moment, you can still return to pick up the bow if you missed it.
Location: Automatically obtained during Chapter 24: The Stadium, cannot be missed.
Location: Automatically obtained during Chapter 24: The Stadium, cannot be missed.
Location: Can be obtained during Chapter 25: On Foot. At the end of the chapter, after you carry the ladder and throw the rope to exit the room with the boat, you will go down the ladder and reunite with Manny outside. On the right side is a building called MS Corporation Soft Drink Distribution Center. Go through the hole in the wall. Inside, you will find a safe with the pistol. The code for the safe is 17-38-07.
Location: Can be obtained during Chapter 28: Hostile Territory. After climbing over the wall, you will enter the Chinatown area with shops on the left and right. Enter the last shop on the left and go upstairs. There you will encounter 2 enemies, kill them, then jump onto the balcony across the street. Turn left and go down into the hole in the floor. You will find yourself in a shop (watch out for infected). Behind the counter, you can pick up this weapon. If you miss it, you will automatically obtain it later in this chapter.
Location: Automatically obtained during Chapter 31: The Coast, cannot be missed.
Location: Automatically obtained during Chapter 34: The Descent. While it can be found in several places, the easiest option is to simply progress through the mission until the game forces you to pick up the Flamethrower, which is near a locked door. You will not be able to open the door until you pick up the Flamethrower, making it impossible to miss. Technically, you could find it a little earlier, just a few rooms before this spot, but you will still get it in this chapter.
Location: Automatically obtained at the beginning of Chapter 44: The Resort, cannot be missed.