The top of the ram on the lee classic turret AND the lee classic cast press is threaded to the rest of the ram. I don't know why this is, might be easier to do the machining to a smaller piece rather than the long ram. The top of MY classic turret turns easily, I just put a ½ wrench in the primer arm slot side ways to act like a lever.
If yours is tight, then that's good unless it's out of alignment. Then, a lever long enough to turn it a bit will get it adjusted. If it turns by itself, and this means it's often out of whack, then a fix may be in order. How I would do that is; to turn it completely off, clean up the threads with a good solvent, then lock tite it. I would use one of the red lock tites, 271 is what I will use if mine ever drifts out of whack.
Just be darn sure it's where you want it, once it sets, you'll have to heat it quite hot to get it to loosen. Once loose, it won't hold anymore, you'll have to re-apply it,(once you clean all the old stuff off.)