Which melee weapons have the longest and shortest attack range?

In order of range:

Disciplinary Action > Eyelander, HHH, Cladhaemaeh Moh, Scotsman's Skullcutter > All other Melee weapons

From the wiki for the Discliplinary Action:

Despite not being listed in the description, this weapon has a 70% longer range than most melee weapons, slightly more so than the Eyelander

I'm making some guesses here, but...

Eyelander, Unusual Horseless Headless Horsemann's Headtaker, and Scotsman's Skullcutter: 8 feet.
All other melee: 5 feet.

The real differences between melee weapons are the advantages and disadvantages listed for each one.

The other major difference is that the Scout's melee weapons always fire twice as fast for half the base damage.

For the most part, all melee weapons have the same range. The Eyelander, as far as I know, is the only exception, and it has a greater range. By what percentage, I'm not entirely sure.