Another few for JR!

Dear Officer, A friend of mine regularly blats along a straight bit of 60 limit road at 140 mph indicated. He hasn''t been zapped or anything, but he''s wondering what the penalty could be if he were? Is there a point where mere speeding gives way to dangerous driving? On a different topic, do county boundaries affect traffic policing? In the sense that would you set up a speed trap, etc near a county border or do forces tend to operate well within their own counties? Cheers GB (Silver Griff 500)