The Target Cannon is a reusable reactive target designed to be used with .22 LR firearms or high powered air guns.
The device has three vertical “barrels” which are loaded with blackpowder. A shotgun primer is inserted into the side of the barrel. The shooter aims at a hole in the front steel plating. Through the hole is a steel plunger that ignites the primer. The result is a big bang and lots of smoke.
It looks like a lot of fun and only costs 25c per target (according to the manufactures website. I do not reload. ). That even cheaper than the poor-mans-reactive-target (pool chalk).
More info at Target Cannon.