> > weaponry ammunitions. Specifically ballista bolts and
> > also crossbow bolts, but also for trebuchets, etc.
Ah, trebuchet ammunition...
Many years ago now, I spent a good portion of an event making
ammo for a trebuchet. I'm not sure if requirements and standards
have changed since then, but if not, what we did worked well:
Take two rolls of toilet paper, place one on top of the other
so that the tubes line up. Cover all but the top hole with
duct tape. Fill with rabbit food, and seal shut. They're
soft, but they've got some weight behind them, and if they burst
upon contact, well, they're biodegradable, and you'll have
vita sine literis mors est