“Reactor” is the third mission in Modern Warfare 3. Several of the main campaign missions have collectible items and weapons to find. This gear doesn’t carry over between missions, but, once you’ve collected it, you can change your loadout both during the mission and any time you replay it.
Our Modern Warfare 3 guide will show you all of the weapon locations and item locations in “Reactor.”
All ‘Reactor’ weapon and item locations in MW3
There are 29 weapons and items to find in the “Reactor” mission.
1. Silenced Holger 556
All the way at the west end of the map, near where you first drop in, there’s a metal building being patrolled by two enemies. There’s a door on the west wall, but it’s blocked. The easiest way to grab this crate is to drop straight onto the roof, but you can get in other ways too — either by heading around to front and shooting the chair to unblock the door, or by climbing onto the shipping containers on the south end and jumping across to the roof. Drop inside to find the Silenced Holger 556.
2. Incendiary MCW
Straight east, there’s a larger building (not the two smaller, trailer-sized ones). There’s a rope hanging off the southeast corner to use an ascender on — if you don’t have one yet, you can find one in one of the buildings you passed. You’ll find the Incendiary MCW in a pallet drop on the roof.
Continue east until you reach another large building with another rope hanging off of the northwest corner. Ascend to the roof and you’ll see an orange platform to the south where you can collect the Sidewinder.
4. Silenced COR-45
From the roof where you grabbed the Sidewinder, take the zip line south, and then turn right. The next weapon is in the round building with a huge E on it. Head inside and climb up the scaffolding. The Silenced COR-45 is in a small orange case overlooking the first Konni helicopter.
Once the first helicopter is destroyed (or before if you’re super sneaky), you can grab the RGL-80 from the case to the south of it.
6. Incendiary Sakin MG38
From the first helicopter, turn west. You’ll see a second-story window in the concrete building ahead of you. Hop through it to grab the Incendiary Sakin MG38.
7. KV Inhibitor
Back outside, look to the south and you’ll spot a huge radio tower. Head over to its base to find a rope you can ascend. Take it up to the sniper’s nest to find the KV Inhibitor.
Turn right (east) from there and look below you at the fire station. On the highest part of the roof, there’s a small room you can enter through the (missing) windows — look for the ⦻ painted on the wall. Inside, you’ll find a broken air vent that will let you see to the ground floor. Shoot the explosive barrel at the bottom of the shaft to unblock the closet door. Drop down to the ground and make your way to the door you just opened for the Minigun.
9. Snapshot Pulse
On your way out of the fire station, you’ll pass the crate with the Snapshot Pulse field upgrade.
10. Incendiary Haymaker
From the fire station, head northeast and through the tunnel marked B1. Hack the turret and deal with the guards, and then you can walk forward to grab the Incendiary Haymaker.
11. HCR 56
The crate for the HCR 56 is just past the Incendiary Haymaker.
12. Heartbeat Sensor
Keep heading north-northeast along the corridor and hop into the round room. Take the ramp on the left up to the second floor. The Heartbeat Sensor will be in a crate on the ground next to a rope. Ignore the rope for a second, though.
13. Silenced Expedite 12
Head to the northwest corner of the building you’re on, and you’ll find the Silenced Expedite 12 next to a zip line.
14. Incendiary FJX Imperium
Head back to where you picked up the Heartbeat Sensor and ascend the rope to the huge crane overhead. Turn to the southeast and follow the gantry to the end to find the Incendiary FJX Imperium sniper rifle.
15. Munitions Box
Just below you and to the west, you’ll see a camouflage awning on a roof. Get down to it to find the Munitions Box field upgrade.
16. VEL 46
From the Munitions Box, if you look to the southeast, you’ll spot a trailer with the Silenced VEL 46 on the roof.
17. Armor Box
Drop off the roof on the south end of the trailer and duck back inside for the Armor Box field upgrade.
18. Holger 26
There’s a Konni helicopter to the southeast of the trailer. You’ll find the Holger 26 in a crate to the south.
19. Cronen Squall
The Cronen Squall is in a crate right next to the Holger 26.
20. Fennec 45
To the northeast of the helicopter, you’ll find the Fennec 45 in a small warehouse.
21. Incendiary Bryson 800
Head through the doors on the north wall of that same warehouse, and the doors leading to the Incendiary Bryson 800 are directly ahead of you.
22. Silenced Lachmann Sub
From the Bryson 800, head northeast through the door marked G5. The Silenced Lachmann Sub will be just inside.
23. Signal 50
Use the various walkways and ladders to climb to the roof of the reactor building. You’ll find the Signal 50 on the southern edge overlooking the helicopter.
24. Explosive Crossbow
From the Signal 50, head northwest across the roof. Hop over to the lip around the dome of the reactor and follow the western edge of that roof. You’ll find the Explosive Crossbow at the far end.
25. Incendiary MTZ Interceptor
From the Explosive Crossbow, look down to the ground on your left (west). You’ll see the Incendiary MTZ Interceptor on the bed of a truck.
26. Anti-Armor Rounds
From that truck, head northeast. Take the first right to jump up onto a ledge and follow the new corridor. Take the first left into the low garage, and you’ll find the Anti-Armor Rounds on your left.
Continue north to the third Konni helicopter. The PILA is in an orange crate to the east.
28. Hybrid STB 556
The Hybrid STB 556 is on the west side of the same helicopter.
Head west from the Konni helicopter and pass through the gate. There’s a small office building to the north. Use the AC unit against the northern wall to climb up to the roof. Smash through the skylight and drop into the blocked office, and you’ll find the Basilisk handgun in an orange case on the sofa.
For more Modern Warfare 3 guides, find all of the items and weapons in “Precious Cargo,” see how to earn the Back in the Field trophy and the A Shot Blocked achievement, or check out our walkthrough for “Deep Cover.” If you’re jumping into multiplayer when it goes live, see how to switch to Tactical Stance, and check our guides on the best Striker loadout, best MCW loadout, and best AMR9 loadout.