Locking wheel nut stuck

[phoenixcsl]

Any of you mechanical heroes know how to remove a locking wheel nut without wrecking my dirty wheel?

The BMW key is rounding off and popping out when I try to undo this locker, I could take the car to BMW but till I get my power steering hose I don't want to drive it.

Was putting my stud kit on yesterday and got the rear wheel and argh stuck fast.

Not happy, I blame the tyre shop for air gunning the wheel nut in just before Spa when I had a new supersport fitted.

The head and collar come off revealing a spline, which looked like my old lockers from my old E46 M3.

any ideas as i'm stumped, tried breaker bar, with wood on it to help keep the locking head on, air gun, impact drive etc to no avail.

Ta