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General | Ordering

Semi-Auto Chassis System

The answer to the call of the discriminating home builder, the Semi-Auto Chassis System at last opens the use of our entire receiver library for custom rifle builds. With the purchase of a hand-matched JP receiver set and an accompanying JP MK III Hand Guard System, receive a 10% discount on the entire package along with hand guard accessories and optional fire control and operating system components ordered at the same time.

Designed to work best together, our new MK III Hand Guard System and receivers provide proper alignment of the hand guard to the receiver, perfect barrel concentricity, extremely high rigidity in the hand guard attachment and rail continuity to allow bridged mounting between receiver and hand guard. In other words, the SACS offers all the benefits of a one-piece receiver system with none of the drawbacks, making it what we call the first "semi-monolothic" system available.

Every SACS receiver set is hand-matched for a perfect fitment and comes complete with charging handle(s) and all upper/lower small components.


Small-Frame Semi-Auto Chassis System
Base Price: $650

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Large-Frame Semi-Auto Chassis System
Base Price: $1275

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