Not to go on too big of a tangent here (as I honestly don't know), but if bullets don't become destabilized as they slow down to a certain point both in velocity and (more importantly) RPM, but still stay transonic, why do twist rates matter? Shouldn't a slow twist barrel stabilize a given bullet the same as a fast twist barrel, as long as the bullet is transonic since RPM slows down as the bullet slows down too right? I was thinking that when a bullet's RPM slowed down at some point it would start to destabilize and wobble, regardless if it was still transonic or not.
I hate to bring so much gun gak into the conversation, but am genuinely curious.
To start, I think you misunderstand "transonic" which (in this situation) is the condition of slowing down to the speed of sound. When they go transonic, as Ted mentioned they can destablize.
Rotational velocity slows far less than linear velocity. Bullets actually get more stable as they go downrange. Slow twist barrels do not rotate long bullets as much as fast twist and since bullet length is a huge factor in stability longer bullets need faster twist rates.
