Why were black powder substitutes invented? I read that pyrodex and t7 aresafe substitutes for black powder, but I can't understand how or why. Don't they all go boom when you put a spark to them?

edelsite

One of the big reasons for sub-powders is they are not suppose to be as corrosive as real BP. Which might be true but you still have to take care of your metal.

Another reason is that black powder is governed under the rules that is an explosive, while the subs are in a less strict category...

Most subs require a greater heat source to start the powder buring and most develope greater pressure but achieve simular velocities...

Most subs are developed to be direct replacement volume for volume of true BP. But even true BP does not follow that rule as different BP's have greater and lesser ability to create pressure. Triple Seven is suppose to be 15% greater in power than regular BP, and in reality it probably is around 10% greater than most BP loads... Swiss BP, a real BP, is generally thought to be the most powerful of the BP. Swiss and T7 are suppose to be about equal.

Somebody with a greater understanding than I will explain it better...

Yes they all go boom. As for why they were invented.. profit margin I would guess.
Black powder is an explosive. The substitute powders were invented to be a cleaner less corrosive powder. They are also not in the same federal classification as black powder. Whether they are cleaner..varies from powder to powder. Also they do not weigh as much as black powder but supply the same power. But if I had to guess it was for the fact they wanted a cleaner powder that got more shots per pound then the conventional black powder.

We always look for something better.

As already stated real black powder is classified as an explosive. Storing and handling comes under very strict rules by federal control. Most retail stores do not have sufficient storage facilities for real black powder but the substitute powders are classified just like smokeless powder and can be stored and handled differently from real black. I hope I explained that clearly and didn't just add more confusion.

There was no thought of a substitute while the flintlock was king. Most all of the substitutes came along rather recently since the advent of the inline and especially when they started using the 209 ignition. Black powder ignites at about 460 degrees while the rest of the subs require from 600 to 800 degrees for ignition. That is primarily why real black powder is still best for the flinters. Black powder is not the least powerful though as APP has that honor according to Hodgdon. The real stuff is all I use and it gets the job done in flintlock, side lock and inline.

Well Pyrodex RS was around a long time ago. When I started shooting it was all Goex or Elephant (if you were unlucky all they had on the shelf was Elephant Brand Black Powder) and then Pyrodex RS came on the market. With a percussion cap traditional rifle it was the answer to a prayer. All the stores carried it, it was inexpensive for the most part, stunk like black powder, fowled like black powder, made big clouds of smoke and seemed very consistent. We were happy again. But like PA Ridgerunner pointed out, when we were shooting flintlocks, it was only black powder.

Actually for the longest time, it was either black powder or Pyrodex. I remember when Triple Se7en and Clear Shot came out. Friends and I tried some of the different ones and did not like them. Powders have came a long way. There is or was; Swiss, Wano, Elephant, Schwitzen, Graf's & Sons, Goex, and other black powders of all grain size. Then there was Clear Shot, Clean Shot, Black Canyon Powder, American Pioneer Powder, Pinnacle, Black Mag3, Triple Se7en powder, Shockey Gold ... did I miss any? Friends and I stuck with Pyrodex RS almost 99% of the time. I finally started playing more with different powders after I retired and started to like the qualities of them more and more.

It was all a money game, why they were invented. New powders were discovered in man's eternal search for better ways to kill each other. Properties of one substance were found appealing in one application over another. Muzzleloaders had to be in there some where. Why are there so many different modern smokeless powders? Wouldn't just one do the job basically? Instead other brands were invented to do specific things.

Market shares is a word they like to throw around in large Corporations, but believe me he who controls it wins...

Dave: You missed Arco and at least one other that slips my mind also.