How fast did the pellet need to go to set off the tannerite? I only ask because I was under the impression the projectile has to have a fairly high amount of energy to set it off.
It wasn't Tannerite, I just named it that for kicks. That was flour in a two liter bottle with about 125 psi filled through one of those caps with the fill valve in them. You can get them at Wally World. The flour is for visual effects.
There is a rimfire reactive tannerite that I have set off consistently with a .20 cal pellet that shoots at about 800 fps. It is the same stuff. The aluminum powder (the gray component) is just ground finer.