Today I figured out I can wrap my static mesh to be a Blueprint inside a StaticMeshActor Blueprint. I moved all the logic related to grande hit detection and explosion to a new BP_Granade Blueprint. When BP_Granade was a regular Actor the Physics Constraint would not work. Now it's working correctly.

My current problem is with instantiating new grande when the previous one exploded. Do I need to hold the static mesh in a variable?