Are you talking about the loot runs? If I don't have any keys, I just slam the outer drawbridge area of the south dam for loot, which has two breach rooms between the down ramps and one of which has 2 security containers... It's almost exclusively player loot; nades gun heals ammo.. If I spawn anywhere near that north to east quadrant, I b-line it there. It's where I farmed during the server slam but I didn't have the security breach talent at the time. I genuinely don't think I have ever seen it hit. Just east of it, at the red lakes there is the hatch exit that is a slide down and run across away.. with two normal extracts relatively close.
I've yet to fully explore other options, I know spaceport has those viewing area's around the launch pad that are breach doors but its more obnoxious to run in and run out.. same to be said with Blue Gate. Buried City, yesterday me and a couple friends started burning our keys for there and it was pretty meh but I haven't found a room yet that is as good. I want to say most blue and up keys have atleast one security container.
I haven't looked at the FoH discord, but I can pay attention more and pop in if you want to run your keys and get into those security containers. Someone had a video on it at the end of the weekend and was constantly getting blues/purples.. but as of Monday, I started seeing like Lv2 white/greens.. so i'm not sure if its ninja nerfed.. but either way I can just throw you out whatevers in there.
ARC Raiders Interactive Maps | MetaForge
theres also this, i haven't really looked at it for loot runs as i'm just kinda running around exploring rather than trying to do a sorta mephisto run simulator.. i just use it to explain to people portions of the map for their tasks.. which also seems to have its own key which is nice.