Interesting, Pierce.  I don't think I would make a self bow out of juniper, no matter what the length.  Too many knots, and too weak in flexion.  I'd never trust it.
Anyway, this bow is 55" ntn.  I was expecting to get more bend out of it, but I think I'd need to get the inners and handle bending to coax out a few more inches.  Since it isn't a bow I plan on using for anything, it isn't worth investing more time.  Might start roughing out some juniper tonight, though.  I got some wonderful pieces the past couple weeks.