Yes, the default meshes already have collision set up.
For future reference (after you learn a little bit of blender :P), this is what I meant by the mesh asset file, in the content browser:
If you open it up you get a screen like this. The blue wireframe is the collision mesh. You can transform it around however you want, add more, delete, etc. There’s a few different basic collision options in the Collision menu. If you delete the collision mesh that’s there and add a new one from the menu it will automatically try to fit your mesh. You can also import your own collision mesh from your 3D software.
Aha, OK. Are you using Unreal’s hit events? If so then they give you the hit location, normal, normal impulse, etc., which should be enough to calculate your bounces I think? There’s a little bit more, rather specific info in the “Hit” structure, if you break that open. I don’t think I understand your setup enough to know what you need though.