It is set to spawn a set distance away from you. Though it shouldn't spawn out of bounds. First I've seen that happen as well. Though if you leave the room and reenter, it'll re-spawn the chest (hopefully in a better spot) allowing you to loot it. I'll poke the devs, but please note that the best way to submit bugs is through the game launcher. It minimizes to your notifications area while in game, and has links to a Bug Report that submits bugs straight to a spreadsheet the devs check regularly and are working off of to get all the launch bugs ironed out.
It was patched in battle axe v6 i believe. And I have submitted a couple of bugs via the launcher. I just didn't want to send an image through it.