OK. The firecracker I prepared above had less in it than a small joint. It was a moderately small bowl's worth. I felt very buzzed after two hours and it got stronger for the next 5 hours, so the peak was around 7 hours! Couldn't sleep before 8 hours. If you don't believe in these things you NEED to try the method I elucidate above.

Be warned though, I was NOT prepared for this and it was VERY intense, just short of hallucinating.