The live fire test has been playing a critical role in evaluating the goals-to-meet of the weapon systems which utilize the power of explosives. As such, the successful development of the test systems therein is quite important. The test systems development covers that of ranges and facilities including system-level key components such as mission control, instrumentation or observation, safety control, electric power, launch pad, and so on. In addition, proper operational guidelines are needed with well-trained test and operation personnel. The emerging weapon systems to be deployed in future battle field would thus have to be more precise and dynamic, smarter, thereby requiring more elaboration. Furthermore, the safety consideration is becoming more serious due to the ever-increasing power of explosives. In such a situation, development of live fire test systems seems to be challenging. The objective of the paper is on how to incorporate the safety and other requirements in the development. To achieve the goal, an architectural approach is adopted by utilizing both the system components relationship and safety requirement when advanced instrumentation technology needs to be developed and deteriorated components of the range are replaced. As an evaluation method, it is studied how the level of maturity of the test systems development can be assessed particularly with the safety requirement considered. Based on the concepts of both systems engineering and SoS (System-of-Systems) engineering process, an enhanced model for the system readiness level is proposed by incorporating safety. The maturity model proposed would be helpful in assessing the maturity of safety-critical systems development whereas the costing model would provide a guide on how the reasonable test resource allocation plan can be made, which is based on the live fire test scenario of future complex weapon systems such as SoS.