Here's my latest batch of plumbatai. It's Gen3, with thicker point material, wider socket and thus thicker shaft, with better shaft wood (beech vs. previous pine/spruce). Still required authentic looks of these, so they have natural feather fletching and nice natural linen thread binding. Lead weights are now cast onto the heads in a 2-piece wooden mold, making them all the same weight and shape.
On the photo, they are accompanied by some roman cavalry throwing javelin heads. Nothing fancy, just a field weapon, most likely one-time deal. Unlike the infantry and their heavy, long-headed pilum, light cavalry had just common javelins with small heads and a leaf-shaped blade. Carried in a large quiver by the saddle. I have one of these heads left, somewhat shorter than these (about 21cm overall), if someonenwas interested.
The modern version of plumbata dart I've mentioned earlier didn't really happen, the customer changed his mind and went period-correct in the end.
Took the picture address from my G+ page, hop it's visible.