Abstarct: In this thesis, while presenting a design process and analytical relationships to investigate the behavior of the Reluctance Coilgun in the transient state, a coil design of a single-stage sample of this gun is being dealt with. This gun will be able to accelerate a 9 gr projectile, from stasis mode to maximum possible velocity, in compliance with maximum current limit and tolearable for the components of the gun. Also, the effect of changing the coil parameters of the gun using finite element software JMAG-Designer 16 has been analyzed and then the results by MATLAB software has been validated. The design process is baxsed on the proposed trial and error method, which will be described in details and the results of its simulations will be presented. Afterward, with the introduction of a new idea, the performance of the Reluctance Coilgun is improved. Finally, a practical gun is designed and constructed, and the results of practical experiments and its comparison with the results of simulations will be evaluated and analyzed.