Poplar. I used to reproduce missing pieces on antique furniture for restoration, and still restore old buildings, The turning was simple, the basic inset I messed up , and had to fill some on the face around the jagged edges. usually I do better, out of practice. Been years since I inset any brass in a rifle, but thats the idea I was trying to duplicated for the insetting. Heavy shell, wanted something solid, and water based castings usually will draw water, so I didn't want concrete or plaster, and I don't have the machinery to do metal. My Father could have though:)