The number of wraps really does make no difference. You see, I first cut two identical pieces of Kanthal based on Ohms per Inch table. I know my resistance before I wrap the
coils. Then I weld non-resistant silver leads to both ends of my Kanthal. Then I wrap my coils knowing that at whatever diameter or number of wraps will not matter. I just target the shape of the coil and it's size. Some times I would wrap an extra turn or two of my non-resistant wire just to make my coil a little more sturdy. Not to mention that non-resistant wire leads are much easier to work with while attaching them under the screw posts or threading them through the post holes. Also, this NR-R-NR method completely eliminates a "Hot Leg" issue and non-resistant wires make much better electrical connection with the posts.
Example: 0.8mm x 0.1mm A1 Kanthal flat ribbon has 5.27 Ohms per Foot resistance. To make my build at 0.5 Ohm, I will need two 2.28 Inch pieces of Kanthal. (5.27 / 12 = 0.439 Ohm/Inch. 1.0 Ohm / 0.439 = 2.2779.... rounded to 2.28 Inches)
As you can see here, even if I made one of my coils at 6 wraps and the other in a single giant loop, their resistance is going to be identical. Of course, their inductance is different, but at DC 4.2 Volts the inductance could be ignored. I don't have to go into explanation of the benefits of using the Flat Ribbon wire versus Round wire, it is very obvious - Flat Ribbon has MUCH more surface area to vaporize
e-liquid then Round wire at MUCH smaller size of wire. 0.8mm Flat Ribbon has its resistance and mass approximately of 28 Gauge wire, but its surface area is of a 24 or even 22 Gauge. Without all that extra current running through 22 Gauge to power it up.
I'm going to stop right there before I will begin to sound like infomercial.
I hope that answers your question.
Mike.