Get rid of him any way you see possible. There are filters all along the route to becoming a pilot that sees to it that no bad seeds actually make it on to the line. If the odd one should pass through all these filters (flight school, interviews, skilltests, PC/LPC...) it is up to either the colleagues or the linechecking system to make sure that that person is removed. I think it speaks for itself, that type of behaviour would never arise if being supervised on for example a line check so it is then up to you as a F/O to relay the information.
You said you tried your chief of flight operations without success. I would then consider writing what we call an occurence report (one that goes beyond the internal auditing system and files a copy directly with the CAA). To me it sounds like an urgent issue so I would also try and call the CAA to highlight the filed report. It's no fun but it is our duty. I've had a similar incident (although it was not intentional recklessness, only pure incompetence) and I was successful with keeping it in house so to speak, but I would have had no problems with taking it to the CAA.
/LnS