I didn't take a close up of the coil but this was my fiddling about at the weekend. Microcoil/cotton build in a russian 91 on an 18350 paps. Tiny tiny coil and a tiny amount of cotton.
.32mm Kanthal 7 1/2 wraps coming in at 1.6 ohms so able to use it on Zmax. was wrapped around a crosshead precision screwdriver so coil is around 1.3mm -1.5mm i guess