Hi Tacklebox,
I hope you will reconsider the use of
potassium nitrate. First, without knowing the exact strength of each particular supplier`s product, it is a dangerous guessing game. And believe me, there are many different strengths found around the world. One might possibly "double" the dose without even suspecting it. Last year, several of us rushed to stop a man in England from using a very concentrated potassium nitrate. Later it was estimated that the amount he was going to use would have probably been fatal. Saltpeter is 100% potassium nitrate (KNO3) and a fatal dose of the stuff is merely 30 grams. By the way, sodium nitrite will cancel your clock at only about 22 milligrams per kilogram of body weight.
Second, there is certainly a reason that it became illegal to use commercially during the mid 1970`s, with the exception of only a few specific applications. When used in bacon that is fried crisp, it produces nitrosamines - known carcinogens. Although it is still used in various cures throughout the world, it is no longer available in cures in the United States (with the exception to only a few commercial wholesale suppliers to the meat industry). In Australia, its use is not recommended although it is still legal. In the U.K., it is still legal and still widely used - something to do with "tradition" I believe.

If you would like to read more about cures, please click on this link:
http://wedlinydomowe.pl/en/viewtopic.php?t=4794
But shucks pard, don`t throw it out. Simply mix 75% potassium nitrate with 15% charcoal and 10% sulphur and you`ll have plenty of gunpowder! Now, why in the hello would you want to eat gunpowder? I totally agree with Jerry in his post above. He makes good sense. Why not use "up to date recipes" specifying sodium nitrate/nitrite? Not that it`s perfect either. Still, it`s a heck of a lot healthier than KNO3 and it won`t blow up in your face!
We still find authors publishing recipes containing potassium nitrate, even though the FSIS has tried very hard to make it unavailable to the average consumer for many years now. Why would you want to use a known carcinogen? I realize that there are many respected authors out there still using it and many are just plain stubborn about accepting modern scientific change. After all, the stuff didn`t kill their grandfathers did it? Never mind that many expired of cancer at a young age, or even more of "unknown circumstances". Another good reason not to use it is because it is about ten times more expensive than sodium nitrite. I realize that I will probably get a flood of mail asking me to "prove" my insinuations. As long as I`ve opened this can of worms, I`ll go all the way and say that anyone who would use potassium nitrate/nitrite as a meat cure after 1975 when they have unlimited supplies of sodium nitrate/nitrite available, must have fallen off their horse a couple of times, headfirst into the cactus. Shucks, its either that or perhaps they just ran the 50 yard dash in a 49 yard gymnasium!
Best Wishes,
Chuckwagon