OnCollisionEnter isn't working between two RigidBodies

I am trying to detect a collision between two 3d gameObjects (it is only detected about half the time):

A bullet, with a Sphere Collider and Rigidbody and Collision Detection set to 'Continuous' (because it is moving very fast).

and a log with a Capsule Collider and Rigidbody (with 'Discrete' Collision Detection).

The bullet has a script w$$anonymous$$ch calls OnCollisionEnter:

 void OnCollisionEnter(Collision collision)
     {
         HitBox $$anonymous$$tBox = collision.collider.gameObject.GetComponent<HitBox>();
         if ($$anonymous$$tBox != null)
         {
             $$anonymous$$tBox.OnHit(damage);
         }
         Destroy(gameObject);
     }

See my screenshot w$$anonymous$$ch shows the trajectory of the bullet going through the log. It's clearly going through it.

And t$$anonymous$$s is what the Sphere Collider on the bullet looks like:

The weird t$$anonymous$$ng is that when I remove the RigidBody from the log, then the collision is detected. But I want the Log to have a RigidBody so it will have gravity.

Also there is no custom Physics layering going on here, so you can rule that out. Please help! Unity version 2019.3.8