A quick test of a single-grain 38mm KNSB rocket motor.

Motor stats:
Nozzle Throat: 10/64" (4mm)
Propellant Weight: 64 grams
Theoretical (from simulation):
Avg Thrust: 18 lb (80 N)
Max Pressure: 800 psi (5.5 MPa)
Burn Time: 0.995 s
Kn Avg: 352