Simple collisions breaking

In my VR project, some objects with very simple collisions arent behaving as they should:

The collision mesh looks like this:

The weapons collide fine when they interact on their short side, but on their long side they seem to ignore each other.
Anyone who has a similar issue, or has any idea what causes this issue?
(Unreal 5.0.0 Preview1, I did not notice this issue in EA2)