I've never been satisfied by the turrets in any of the Hoth sets (and there must be half a dozen versions of it by now). They all have the problem of a straight cylinder, when in the movie the turret clearly tapers. I've made a number attempts at building one. Now I think I've finally cracked it.
DF.9 Turret by James Shields, on Flickr
DF.9 Turret Front by James Shields, on Flickr
DF.9 Turret Overhead by James Shields, on Flickr
James