The engineers at the Naval Surface Warfare Center in Crane, Indiana, have developed a new takedown system for precision rifles that does not require re-zeroing after disassembly and assembly.
NSWC Crane built a prototype of the design using a modified Mk 13 precision rifle, which are currently in use with SOCOM and soon to be fielded by the US Marine Corps as their replacement for the ageing M40. The patent application for the new takedown rifle credits the invention to Michael H. Jones but notes that it was the work of employees of the Department of the Navy – at Crane.
The rifle breaks down into three assemblies: barrel assembly, receiver assembly, and stock. The two primary assemblies are secured together by a locking pin while the bolt also acts to lock the assemblies together. Alignment is ensured by a series of guide pins and locking tabs. While this pin is not captive the patent states it can be stored in the barrel assembly. The photographs taken from the system’s patent do not show which assembly the optics would be mounted to but the patent description explains that they would be mounted on the barrel assembly to avoid the need to re-zero.
The patent states:
By using this exemplary approach, it will be possible to break down a rifle so that it may be carried within a briefcase or other similarly sized container, assembled, and used to engage a target at 500M without a need to re-establish zero.
The compact nature of the weapon system has clear advantages for transport and deployment in the field. The new design is available for licensing by private sector companies for further and new product development.
Patent Application: Improved Takedown Precision Rifle, 18/01/18, (source)