Slit518
Adventurer
A bit Academic mixed with Mechanical.Given that background and that youre not familiar with Traveller (which is a long established and influential sci-fi system) I am wondering why you are considering metric, is it purely academic?
I was just thinking of the difference in reach for example from a Dagger, to a Longsword, to a Greatsword for example.
I would say on average the tip of a peck to the end of a knife is about 1 meter.
A Longsword wouldn't quite give you a 2 meter reach, but it may be on the cusp.
A Greatsword I am sure you could swing at a target 2 meters away.
I'm not a weapons expert though.