
To unlock Gunsmith 3 in ARC Raiders, you’ll need to collect 3 Rusted Gears and 4 Sentinel Firing Cores.
These materials can be hard to find, particularly if you’re not sure where to search. But once you know where to look, it mostly comes down to patience and a little bit of luck to collect enough.
I can’t promise to bring you good luck, but I can definitely point you in the right direction to find what you need!
Where to Find Sentinel Firing Core & Rusted Gear | ARC Raiders – Unlock Gunsmith 3
Sentinel Firing Gear

Let’s start with the Sentinel Firing Core. You get this item by defeating Sentinels, which are typically found on the outside of buildings – as we explained in our guide to all ARC locations.
Based on our findings, the Dam Battlegrounds map is the best location to farm Sentinels. We’ve identified two particularly good areas where they appear.

The first location is north of The Breach, on the northern side of the map. You’ll typically find a Sentinel guarding one of the towers there.

To find the second location, head to the Research & Administration building, which is near the map’s center. Keep an eye out for a Sentinel that might appear near the top of the building, specifically on the eastern staircase.
This next area can be dangerous! A lot of players are hiding there, waiting to ambush others and steal their items, so be prepared for a fight.
Sometimes, the Sentinel in the second location can have a bug. Its movement can become erratic, causing it to float away and become inaccessible, though this doesn’t happen often. It’s good to be aware of this possibility.
Even so, these are the two best places we’ve found to collect Sentinel parts and their special equipment. You’ll still need a little luck when fighting them, though!
Rusted Gear

You can find Rusted Gears by searching containers in Industrial areas. We recommend checking the Parking Garage in the Buried City map for a good chance of finding them.

This garage is quite tall and filled with wrecked cars you can search for items. Each car has a chance of containing Rusted Gears, so be sure to check them all as you explore upwards.

Just a heads-up, Rusted Gears are pretty rare. I had to farm that spot for a while before I finally got enough of them, so don’t get discouraged if it takes you a few tries!
That’s everything you need to know to find the Sentinel Firing Core and Rusted Gear to become a Gunsmith 3 in ARC Raiders! Good luck with your scavenging, Raider, and don’t forget to use your Safe Pocket!
Looking to improve your Gear Bench? We have a guide explaining how to get the Industrial Battery and Bastion Cell to help you do just that!

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2025-11-06 03:06