I just used coiltoy real quick to come up with some ballpark numbers. I personally wouldnt aim for the 0.2 ohm spot, but that is just me.
These are assuming 5mm free length, no spacing, and the number of wraps are for each coil(this is assuming you are doing a dual coil).
1mm drill bit
11 wraps --> 0.2 ohm
29 wraps --> 0.5 ohm
1.5mm drill bit
9 wraps --> 0.2 ohm
22 wraps --> 0.5 ohm
2mm drill bit
7 wraps --> 0.2 ohm
18 wraps --> 0.5 ohm
2.5mm drill bit
6 wraps --> 0.2 ohm
15 wraps --> 0.5 ohm
3mm drill bit
5 wraps --> 0.2 ohm
13 wraps --> 0.5 ohm
Depending on the price, you can probably pick up more than one of the drill bits. I know I got my drill bits on amazon for pretty cheap(under 3 bucks per drill bit). If the store is kind of pricey, I would just say to get a 2.5mm to start with and do 10 wraps per coil. That should put you at roughly 0.3 ohms. As always, be sure to check your build on the ohm meter before you use it.