I also can confirm that if you empty a 60 bullets magazine you got that 60 bullets in one slot but you can not combine e.g. two times 30 bullets to 60

Can confim that you are also able to jump through openable doors etc.

duplicate

Happens to me too, but I guess there is a connection between the quality of the item and the time it takes to appear. I drop my prestine case -> it instant appears on the ground. I drop a badly damaged one -> it takes about 30 sec. to appear on the ground.