I've never had an estwing hatchet, but we've got one of their axes. Very old. The handle section is indeed hollow, but there is absolutely no flex or vibration in it. It feels like a solid bar of steel all the way through, not just friction fit and crimped. If you made it solid, in that size, the balance would make it a very inefficient chopper. A solid steel handle like your scratchets and crash axes requires a very different style of head to make the balance come out right (and the handle is not even remotely hand-filling, either).