If I sound a bit annoyed, perhaps it is because (a) it is late at night, I
just downloaded 75 emails which I have to read, or (b) I am just a natural
grouch.  :-(

Well, folks, if you are worried about Potassium Nitrate blowing up the place,
how come you are not worried about all of those home made CO2 bombs you are
using to supply CO2?  If you really DO want to have a nasty explosion, just
mix your good old CO2 sugar and yeast mixture, and then TIGHTLY CAP THE

It will explode in a not too great amount of time, (a few hours, usually)
with a really HELLISH bang.  Also leaves the darndest mess about the room!
 Fermentations develop tremendous pressure, especially during the early
stages of fermentation. Home wine makers have experienced some real
cannonades, as one bottle exploded, setting off the others!!

As a wiser than me person already said, almost anything can explode, if you
work hard at it.  8#D