I don't know what a Zulu looks like, but it seems to me the cone-shaped design of a Dublin would be ideal for a horn shaped pipe. It would fit in naturally.
Of course, I have a black dress Nording freehand that is somewhat horn shaped and is also a Dublin, but it's big enough to fit any size chamber. Strange: haven't seen those black dress pipes in awhile. They're great, effortless smokers.
Apparently I really scored with this pipe. I searched the net and can't find one like this Jack anywhere. It might be a new wrinkle on Nording's carving of these pipes. I've asked SP to keep a look out for another one for me: it's not only great looking, but a great smoker as well.