Apologies for the title, but wasn't sure how to best describe this succinctly.

Playing on the 1.08 Experimental Branch for Xbox, I looted a box of rubber slugs from the police station in Elektro. Some time later, I looted a box of rifled slugs from a deer stand. When I looted the rifled slugs, I did not manually move them into inventory, just quick grabbed them with X. A few moments later I was in inventory and noticed I now had two boxes of rubber slugs. At the time, I assumed I had been mistaken about the rifled slugs but I was streaming and just reviewed the video. The second box was, indeed, rifled slugs but showed in inventory as rubber slugs.

Happy to provide a link to the video if needed.