You can Easy Reproduce this:
Make fresh First Person Template press Play and go really close to cube and shoot then check Outliner
you will see that it is filling up with deleted actors and they are not removed from Outliner
It looks like it works from distance but when you are close to object they stay.
Hi Positivity,
This is a known issue in 4.7, reported here:
Keep an eye on that post and we’ll update it as soon as we see any progress on bug. Thanks!