Exactly. This is a pic of the hairspring I'm working on. My horizontal v vertical rates are all over the place. There is no discernible terminal curve. My problem is that the outer coil is (possibly) hitting the regulator pin. It's hard to tell but it looks to be getting very close. Also getting close to the stud, which could be @VWatchie's problem.
You can see that I need to adjust the inner coil to centre the collet. That will hopefully solve the problem. But then I'll take the spring off and attach it to the cock to see how it looks.
I don't know if it's causing your problem @VWatchie, but I would say your inner coil looks like this