That sounds like the bates grain. I prefer end burners for their simplicity and constant thrust. With sufficient choke their performance is good enough.
I'm using them as gas generators more than rockets though. I have plans for a small computer-controlled lander platform with a central gas generator and pipes leading to motors with servo-controlled valves. It'll use heritage hardware from wrecks of these machines and some extra Arduino coding.
I'm using them as gas generators more than rockets though. I have plans for a small computer-controlled lander platform with a central gas generator and pipes leading to motors with servo-controlled valves. It'll use heritage hardware from wrecks of these machines and some extra Arduino coding.