I run the mandrel or needle I used to make the coil through it after each of several heat to glowing cycles. I also pull on the mandrel a bit to try and tighter up the wraps and straighten the legs. If still there after several heat cycles I trash that coil and start again. I only get them about 1 in 15 times now.
I've been doing that. I think part of the problem is the length of the legs and the curve - 28g. w/ 6-7 wraps. The other part of it is me doing the same thing over again and expecting a different result. LOL