poppers/blanks for dog training

[wildwings]

Anyone have an idea how to make poppers for a 12 guage? I have tried my usual 12 guage trap load...minus the shot, but it's very quiet. Any ideas? Need them to do some dog training, to make sure they won't become gun shy. Currently I'm using a 209 primer cap gun.Unfortunately, money is a tight commodity now with the holidays, so I can't afford to buy the poppers.