Well, the verdict is in. The Missouri Meerschaum (MM) corncobs that JBD sent me win.

The biggest, fattest and heaviest corn ears were Boone County Kentucky (BC) corn (seed from BigBonner). They were bigger and fatter and heavier than the MM corn ears. However, once the tall, dense, heavy kernels were removed from the BC corn, the dried cob turned out to be quite a bit smaller than the MM dried cob. In addition, the hard, woody center of the MM cobs, though no denser than that of the BC cobs, is wider, and can be drilled to a larger diameter tobacco hole for a pipe bowl.

Now, my BC corncob sitter pipe is still a substantial pipe, but a thicker cob would have allowed a somewhat larger bowl capacity. I've made a number of other corncob pipes from cobs of other varieties. They are quite nice to smoke, but they are smallish.

If you want to home-grow the best corncobs for a pipe, plant the MM secret variety seed. The only source that I know of for these seeds is
For $10, you get the seed, plus 2 drilled hardwood stems and 2 MM pipe bits. Missouri Meerschaum itself ( doesn't appear to offer the seed directly.

I suppose that had I planted a hundred or so BC seeds, I might have turned up a comparable cob in there somewhere, but then I would have ended up with a couple of dozen pounds of dried, shelled, field corn. There is a limit to how much hominy grits and cornbread I can consume in my life.