Until I save up for briar, I am working with what I have: a covered hardwood pile that's been aging for 5+ years. Mostly sugar maple, cherry, oak and the occasional ironwood.
After having a couple (4) blocks tear out and blow up on me on the lathe, I simplified my process: drill the hole for the shank, drill the chamber, turn the stummel and shank separate and fit them. It worked. mostly. Hophornbeam turns like steel until you catch the grain wrong. I tried at least 3 different grain orientations with no success.
Last and least, Ash sucks for a shank. It splits when you cough on it.
American hophornbeam, cob style
Re: American hophornbeam, cob style
Missouri meerschaum uses a small metal ring on the end of their shanks to prevent splitting out. Maybe you could do something similar? Looks like a pretty decent little hardwood pipe.