Concept MSBS GROT Rifle Upper Receiver Shield to Protect Against Foreign Objects

This paper presents a concept for shielding the MSBS (Modular Firearms System) Grot rifle upper receiver against foreign objects. The concept guidelines involve feedback from Grot operators concerning the regular operation of the rifle plus an extensive analysis of desktop patent research into foreign debris shields (or dust shields) for protection of the upper receiver interior in firearms. The completed patent desktop research included solutions used with automatic, semi-automatic and non-automatic firearms. The research work drove the formulation of the requirements for an upper receiver dust shield for the 5.56 mm calibre MSBS Grot rifle as part of the ongoing improvement process. This paper presents three concepts of the carrier charging handle assembly dust shield (for the protection of the upper receiver against foreign objects) for the MSBS-5.56 rifle system. The concepts described vary in terms of the level of structural complexity of the dust shield, and the extent of the modifications required to the upper receiver of the rifle. With test units of the upper receiver dust shield manufactured and comparative tests completed on the three concepts, the version selected should be the one which improves the protection of the rifle internals from foreign objects found in the local environment, including sand, clay, silt, and mud, the latter being an aqueous suspension of these particles.