I mis spoke, the blank i have at home is a Krieger #5, which from a few dimensions I compared is the exact same as an ace 3 and a bartlein 3B.
Keep in mind your shoulder is going to be.6” short of your desired length, so factor that in.
Shanks appear to be the same length as well. So you can likely get close.
The mark is .750, for reference my 21” ace is .748 at the thread shoulder.
If you want to go shorter I would honestly try to track down a bartlein 3, Krieger 4 or ace 2. We really should approach UM and see if they will come out with an OG contour for us, essentially a 730-750 taperless. Skinny shank would be an even better sell too.
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