Semi-automatic rifle
Patent No. US9683800 (titled "Semi-automatic rifle") on Dec 14, 2015. The application was issued on Jun 20, 2017.
What is this patent about?
’800 is related to the field of semi-automatic firearms, specifically those designed to emulate the aesthetics and mechanical features of military-grade light machine guns. The invention addresses the challenge of adapting a platform typically designed for fully automatic, open-bolt operation into a civilian-compliant, closed-bolt semi-automatic system that retains the ability to utilize both belt-fed and magazine-fed ammunition sources.
The underlying idea behind ’800 is a specialized firing control group that utilizes a sliding hammer riding on internal receiver rails to strike a firing pin housed within a rotating bolt. Unlike traditional hammer-fired rifles that use a pivoting component, this design employs a linear-motion mass driven by a dual-spring system to ensure reliable ignition while strictly enforcing a semi-automatic cycle through a sear that resets immediately after the hammer is released, regardless of trigger position.
The claims of ’800 focus on a receiver architecture that integrates a dual-feed system—comprising a magazine well and a pivotal top cover for belt ammunition—with a unique coaxial spring arrangement. Specifically, the independent claims protect a mechanism where an operating group spring and a larger-diameter firing spring are nested coaxially and pass through a central hole in the sliding hammer, providing the necessary force to drive the hammer forward while managing recoil energy.
In practice, the rifle operates by using a bolt carrier with a specific longitudinal slot that allows an extension of the sliding hammer to reach through and strike the firing pin. When the trigger is pulled, a disconnector pivots the sear to release the hammer; however, the sear is spring-biased to return to the catch position instantly. As the bolt and hammer recoil together following a shot, the sear catches the hammer on its return stroke, preventing a second discharge until the user manually resets the trigger.
This implementation differentiates itself from prior art by combining the belt-fed geometry of a machine gun with a linear striker-style hammer system that is physically separated from the bolt carrier's forward momentum. By decoupling the hammer's release from the bolt's closure and requiring a full trigger reset to move the disconnector, the design achieves a reliable semi-automatic cadence while maintaining the rugged, heavy-duty feed requirements of a belt-fed platform.
How does this patent fit in bigger picture?
Technical Landscape
In the mid-2010s when ’800 was filed, the design of semi-automatic firearms for the civilian market was typically implemented using dedicated receiver architectures optimized for either magazine-fed or belt-fed operation, but rarely both simultaneously. At a time when systems commonly relied on fixed feed geometries to ensure cycling reliability, the integration of belt-fed mechanisms into platforms maintaining a semi-automatic trigger group was often constrained by the mechanical requirements of the belt-pulling cycle and the need to prevent fully automatic fire. Engineering constraints of the era made the transition between disparate ammunition sources non-trivial, as the bolt and receiver assemblies were generally specialized for the specific spatial and kinetic requirements of either a vertical magazine well or a horizontal belt-feed ramp.
Prosecution Position
The disclosed invention represents a technical advancement through the integration of a dual-feed receiver architecture that accommodates both belt-fed ammunition and standard magazines without requiring structural modification. This architectural shift is enabled by a receiver housing featuring internal rails that guide a sliding hammer, ensuring consistent alignment and kinetic energy transfer to a firing pin carried within the bolt assembly. The system achieves a specific technical effect by incorporating a trigger assembly with a dedicated disconnector and sear arrangement that enforces semi-automatic operation while providing tactile and audible feedback via a spring-loaded pin mechanism. This configuration overcomes the constraint of maintaining light-machine-gun ergonomics and feed versatility while ensuring the mechanical separation of firing cycles required for semi-automatic platforms.
Claims
The patent contains a total of 20 claims, with independent claims 1 and 10 focusing on the mechanical architecture of a rifle that incorporates a belt-fed ammunition system, a pivotal top cover, and a specific firing mechanism utilizing a sliding hammer with a central hole. These primary claims detail the integration of a dual-spring system for hammer propulsion and a trigger assembly featuring a sear and disconnector designed to manage the release and reset of the sliding hammer. The dependent claims serve to further define the structural components of the firearm, specifying details such as the coaxial arrangement of the firing and operating springs, the inclusion of internal guide rails for the hammer and bolt carrier, and the addition of ergonomic or protective features like heat shields, hand guards, and carrying handles.
Key Claim Terms New
Definitions of key terms used in the patent claims.
Litigation Cases New
US Latest litigation cases involving this patent.
Patent Family
File Wrapper
The dossier documents provide a comprehensive record of the patent's prosecution history - including filings, correspondence, and decisions made by patent offices - and are crucial for understanding the patent's legal journey and any challenges it may have faced during examination.
Get instant alerts for new documents
US9683800
- Application Number
- US14968131A
- Filing Date
- Dec 14, 2015
- Publication Date
- Jun 20, 2017
- External Links
- Slate, USPTO , Google Patents