if your just designing reuseable ammo your wasting time
in the time it'll take you to make one round you could make 50 disposable rounds that double as cheap grenades, and it costs me about 3$ for 100 rounds
take two styrofoam cups, an exacto blade, a roll of electrical tape and a handful of BB's and get manufacturing
its simple, its easy, it works, its tested and its safe, just make sure you buy the rocket launcher before you start making them
-thundercactus