I'm a sprue stretcher as well.
Practice with it, it has many more applications than just making antennas. Varying the amount of time over the flame determines how thick/thin the "stretch" will be. Less time, means less heat, resulting in a thicker stretch...usable for anything round (tubing/plumbing, scratchbuilt control sticks, etc.). For fine "wire" hold the sprue over the flame till it bulges and sags a bit, stretch your arms out farely quickly, and you'll end up with a farely consitant, fine "wire". The slower you pull, the thicker the "wire".
Practice, practice, practice.