I just looted Small Train Turret
While shooting this hidden wreck in Hokkaido, the one with trade line parts.
Hidden wrecks are realising loot after the first shot, but I used to shoot them some more, till they explode (some of them will explode, I mean). Now, when this Train exploded I immediately tapped "tractor everything", not really expecting anything to happen. And, to my supprise, I looted myself Small Train Turret. It can be mounted at any weapon slot, both as turrel or as the main weapon and when unmonted it takes up 50 units of cargo hold (so you must fly a frighter with empty cargohold when trying to loot one). Maybe, if I was in the Dromadery at that time, I could get larger turrets too...
I'm not running any mods, but I installed unoficial patch 1.4 so, at the very least, it can be some unintentional feature of it.
Maybe I'm making fool of myself as it is hard to belive that you can finfd out something new in the game this old but I cannot find anything about it here.