Front mech shifting - not working at both ends of cassette

I have a Campag Veloce 53-39 on the front and a 12-25 cassette on the back - i'm in the process of replacing the gear cables and coming across a problem trying to tune the front mech in:

• To get the 'inside' shifter on the mech to engage (i.e. to move from 39 to 53), I need to unscrew the H screw so far that it ships the chain off the outside of the chainring.
  
• In 39-25, I have to uncrew the H screw so far that there is a good 3-4mm gap between the chain and the 'outside' shifter on the front mech when it finally shifts to 39-12.
  
• In 53-12, it shifts down fine into 39-12, but then shifting back up to 53-12, there is too much of a gap between the mech and the chainring so that the chain is shipped off the outside again.
  
  

Some pictures of the extremes in shifting:

To me, it seems almost like the gap between the 'inside' and 'outside' shifters on the mech itself are too far apart, but the bike hasn't been crashed and I don't know how that gap might have been stretched in the first place.

Any ideas? Is it wrecked or am I being a nonse?