SpudFiles

1. Tape the cup for the nose cone to the pipe
2. invert
3. fill with concrete
4. insert second cup into pipe to form the hollow tail

No need to cut a hole in the nose cone cup, or the other cup for that matter.

No need to cut a hole in the nose cone cup, or the other cup for that matter.

... though you'll probably need to add a few weights to the tail end cup to keep it in place.

Quikrete is CHEAP! Batteries = Not cheap!

Make it a bit small and wrap it in duct tape to prevent wear in the barrel.