That seemed to work well Jim.
I did a similar lead pouring project making 10# downrigger weights for fishing deep. I used either Maple or Hickory (can't recall) and turned on the lathe two small shallow bowl shaped recesses in 2+" thick wood that matched and could be clamped together so they formed a disc shape. I had two register pins in the wood to keep them aligned. I added a pour hole in the top side and a recess so I could insert an aluminum fin sticking out the back before the pour. The wood was soaked in water for a couple of days before pouring so I had to be careful of "steam" on the first pour. I made several weights before the wood was too charred to continue. The weights worked much better than the usual round balls many people use.....less drag in the water.