Picked an artillery turret ghost and tried to place it where it could fire on a choke point. Tried again after crafting an artillery turret and holding it in my cursor.
2. What happened?
No range circle (either minimum or maximum) was displayed, whether on the surface view or the zoomed out (pixelated) map view. This happens whether you have the actual artillery turret item in hand, a ghost, or a blueprint containing artillery turrets - no range preview overlay is shown.
No range circle overlay is shown with an artillery turret ghost selected in the cursor (train tracks placed as a ruler - the 32 tile minimum range is well inside the bounds of the screenshot):

The same is true with a physical artillery turret held in the hand; no range circle is displayed:

Only after the turret is physically placed does the turret coverage ring (showing both the minimum and maximum range) display, and even then only in the zoomed-out map view, not at the surface level zoom:

3. What did you expect to happen instead? It might be obvious to you, but do it anyway!
A range preview circle should be shown when placing turrets, so you know how far they can fire and what area they cover, whether as a physical item in hand:

Or as a ghost:

I'm pretty sure artillery turrets used to have a range preview circle. Either way, correctly placing artillery turrets without a range preview makes it extremely inconvenient and time consuming, especially if they're being placed by a roboport network with long travel times between the artillery turret source and desired location of the turret.
4. Does it happen always, once, or sometimes?
Always