I have made all types of darts, but my favorite for just plinking would be wire nuts, ( connectors for electrical wiring) I find the size closest to the bore of my blowgun, add a piece of tape to the tail if necessary, and shoot away I have never used them for hunting , but they are davestating on soda cans at reasonable range.
These are some of mine. Four different wire dart variations. A couple blunt or stun darts. And what i call a spike dart. The orange dart is one of my origial darts from my first blowgun. The tip is square. In some instances it works better than pointed. It's like a paper punch.