Windows 10
Assus Strix 780 6gb

2.77.1 abf6f08

Wrong scale information somewhere in FBX export file I think. When I created cylinder with 6 bones for example and export it with scene scale 1 and export scale 1, mesh have right scale but physics assets explode when simulated. I find that if set scene scale in blender to 0.01, Scale objects by 100 and after that export FBX with scale 1 in setting physics assets in UE4 works well.
btw in Maya for example all works well with default export settings.

1. Create cylinder
2. Create 6 bones inside Cyl
3. Parent bones with auto weights
4. export FBX
5. import FBX to UE4 with generating physics asset
6. Open physics assets of Cyl file
7. Play simulation