Thanks for the comments.
The arrows with the wood points are from a wood called Massaranduba , a very hard tropical wood. I drill a taper hole in the wood and sand a corresponding taper on the shaft, glue them on, then finish sand them on a belt sander. The blunts are made in a similar way but I glued a tight fitting ring of copper at the front end to prevent the wood splitting, thought it would look better than the rubber heads you can buy. The other arrows have a M6 screw shank glued into a drilled hole (about 1 1/2 inches deep) then finished on the belt sander. The wood points are quite durable and have withstood hitting trees, rocks are a different matter.
Peter (UK)