Better explosion?

[numberPI]

On a project to be presented, I am on the need to find what would create a better explosion between black powder, propane gas, gasoline, or else on a controlled environment (such as a 1/2 inch-thick steel chamber) to propel a metal spud into the air at high speeds.. can somebody help?

'numberPI

[Chemicalsuperfreak]

Black powder, it's the only high order explosive of the three, that's why it was used to propel large metal objects into the air for hundreds of years. Natural gas and gasoline just burn very quickly, they only really explode if a large amount of fumes are allowed to build up in one place.