Can someone who is familiar with this sort of science explain what this sentence means?
Specifically the second part.
>Helical railguns are multi-turn railguns
>that reduce rail and brush current by a factor equal to the number of turns.

If it reduces the current, wouldn't that make it weaker? Are they saying helical railguns are weaker than regular ones?

Also
>The helical railgun is a cross between a railgun and a coilgun.

How does that make sense? Doesn't a railgun have to two seperate rails, which are charged differently? A coilgun only has one rail, in the form of a coil.

Also
>They do not currently exist in a practical, usable form.

Why not? What makes them less practical or usable than regular railguns?

https://en.wikipedia.org/wiki/Helical_railgun