My whole arsenal of pub darts! I got a lot of damaged flights that can be used for experiments. Won't mess with the brand new stuff, expensive precision tools!
I suggest using cheap nylon shafts and made in china flights for your experiments, that aluminium is quite heavy, will throw off your balance at such length.
Edit: There is one short stubby aluminum shaft suitable for this, for flights get the Slim flights. The longer ones get bent very easily.