Need help creating exploding targets
I'm sure everyone is familiar with tannerite. Well, I'm trying to make something that will explode with a much lower velocity projectile, such as from a BB gun. I had an idea I thought would work perfectly, but it doesn't. I bought some of those pop-rocks, you know those little bags you throw at the ground and they pop like a firecracker. I took a big plastic straw and held it closed with pliers and melted one end closed. Then I opened the bag and poured the little rocks inside, followed by some gunpowder. Then I sealed the other end of the straw, probably about 2 inches long total. When I throw it at the ground, the rocks will ignite but the gunpowder will not. But if I take the left-overs, and hold a flame to it, the gunpowder will burn. So I'm scratching my head as to why this doesn't work.
So any ideas how I can fix this? Or any other ideas how to make an exploding target? Noise isn't entirely what I'm looking for. I want to be able to place these inside of objects, such as a fruit or potato or something and have it explode when I shoot it. ANy thoughts?