see the video. 3 sec. hang timefor the candy. container didn't leave the barrel because of loose seal.
Step 1: First you need a large barrel potato gun.
Step 2: The ignitor.
Step 3: The firing button.
Step 4: The most important part.
When you are done, cut off the excess, and see if it fits tightly.
Now, for a little strength and better compression, wrap the surface that will contact the barrel with some electrical tape.