Your wood is fine, depending on where you live your wood will stabilize at the MC average for your area. Hickory likes a low MC for the best performance, even 6% isn't too dry.
I have made several BB hickory bows, all were right up there in performance with BB osage bows. All were made from sub par solid hickory bows that I narrowed and backed with bamboo for other people. Essentially I used a somewhat worn out hickory core, backed it in a reflex, heat treated the hickory in some cases, retillered and made some mighty fine bows. All the original hickory bows were made by other people except one. This bow was my fifth when I had just started out and believe me it was "sub par".
Anybody who says BB hickory is a bad combination is probably a keyboard critic who has never actually made such a bow but is quick to offer an opinion like it is a fact.