After a long absence I'm going to utilize some down time to tackle another bow project. The hedeby/viking long bow has danced around in my head for a couple years and I'm finally going to try one. I want to stay as close to the originally design and length as possible, (and have access to either hackberry or hickory ). My question-using a stave from a small tree with a radius of approximately 6" the back is going to be fairly high crowned. Does anyone know if the originally bows had a naturally round back or if it had been scraped flat? Thanks