There's a point past when you have to pay a surcharge if the length plus the circumference add up to some certain number, don't remember what the magic number is, but I've shipped plenty of six-foot long things over the years. For staves, I usually just wrap them up really good in several layers of saran wrap or pallet wrap. Saves money. You can tape two of those triangle 36" priority boxes together to ship long things, but for a bow, I'd go with the PVC or carpet tube.