variable communicationproblem

hello everybody,
i work on a shotscript. At my CharacterBP i used a spwanActor-Node to spawn a bullet.
http://gyazo.com/c8e35f741bfdc0d5895825be49612bfc
After spawning this bullet i set some variable, how you can see on the screenshot.

If the bullet interact with an other gameobject it will be destroyed by the Bullet-BluePrint.

This works good, if this bullets interact after a large distance of fly with other objects.
But if the distance is to small, the variables (s. screenshot) are not known. e.g. the Creator = NONE.

What is the reason for this problem, and how can i solve this ?