You can end--burn APCP (Ammonium Perchlorate Composite Propellant) and get low-thrust rocket motors.
You can only core-burn KNO3/Sugar or KNO3/Epoxy motors and expect any sort of aprreciable thrust. The amount of thrust and burn time can be adjusted by core geometry and nozzle size.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !