Yes. Both of my mortas get quite warm. They have less porosity and more density than any of the other popular pipemaking mediums (briar, cob, meer).
The Lovat I have from Todd Harris has a tall bowl with thin sidewalls to the chamber. Fortunatey, grasping the pipe like a cigar and moseying on smokeward seems just fine. The cherrywood-esque shape "bent poker" shape is fine in the top half of the bowl while in use, but due to the wider top and narrower bottom (while the tobacco chamber stays the same dimensions) it gets noticeably hotter toward the bottom. I simply hold the pipe higher up the bowl toward the top.
I've learned recently to detect too-hot combustion via the smoke itself (moisture, heat, flavor) so I know I'm not overworking the pipe while smoking. Morta just seems to conduct heat a little more easily.
I think bulldog, squashed tomato, or any other pipes that would allow a bit more material at the sides where being held is probably a good idea. Especially if you're a "holder" more than a "clencher."
Or, just adapt accordingly.
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