© 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Nozzleless Solid Propellant Rocket Motor (NSPRM) is a concept choice as a booster motor for tactical missile systems, propelled by Integral Rocket Ramjet. In this work, examination of flow field inside the grain port and regression characteristics of grain itself of a NSPRM are presented. Results are obtained via quasi steady state time simulations, solving numerically through flow inside the motor using quasi one-dimensional Euler equations including instantaneous mass addition. Flow properties and erosive burning rate contribution along the grain is examined. To investigate the effect of grid length, results of simulations, repeated for two different grid sizes, are also presented.