Minigun is something you are really going to need in your Fallout 4 journey, even though you might don't know it yet. Since we love you, by the way, we are here to explain how you can get this minigun for you to use as soon as you will understand why it is so important.
Head to the northern part of the map, specifically at USAF Satellite Station Olivia (north of Concord), and once you're there you have to descend as down as possible. After the first door, run through the hallways, then go slightly left and turn right to descend even deeper. There you will have to beat some enemies, do it, and you will probably notice in the last room on the right there's a minigun lying on the ground (it is there from the start, no enemies drop it in the game).
While getting back to the surface, at the first floor of the facility you will also notice there's a locked door. At the same floor where you found the minigun you should have also got the key for it, otherwise you can also try and unlock it on your own if you have enough skills. Behind the door you will find one of the stealth boosting magazines called U.S. Covert Operations Manual, which will provide you with one stealth point.
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