Real BP (Goex/Swiss) is an explosive, substitutes are propellants. Big difference.
I'll go you one further. Substitutes AND smokeless powder are explosives.
Many people (even other EOD tecs) will argue but if you don't believe me stick a blasking cap into a can of BP Substitues or Smokeless powder.
The difference is what it takes to get them to explode.
Actually an Explosion is nothing more then a "fast burning rate". Burning rate (how fast it burns is what seperates Low and High Explosive.