The KNS Precision AR-15 Perma Firing Pin Retainer was inspired by the design of the retaining pin found in the original AR-15 prototype developed by Eugene Stoner. The pin retainer ensures that the firing pin remains secured into place and works with any standard AR-15 bolt-carrier group. The pin retainer is made from heat-treated steel, which provides flexibility and strength. The pin cannot be used on .308 bolt-carrier groups.
- Enhanced tunability of operating system
- Guaranteed reliability of difficult configurations
- Overcomes all fouling build-up
- Roller-burnished bore for frictionless operation
- Rock-hard QPQ finish provides remarkable natural lubricity
- Extremely smooth cycling with proper lubrication
- Increased bearing surfaces for slower wear and longer component life
- Longer cocking pad for optimal reliability
- American made
The large-frame VMOS™ carrier uses the same steel and tungsten weights as GEN 2 Silent Captured Spring units. Only the forward two masses are reconfigurable. The rear-most steel mass cannot be exchanged.
This carrier will not cycle with a standard buffer retainer plunger installed. Standard buffer/spring components must be installed “loose” or replaced with a Silent Captured Spring.
This notice pertains to any rifle based on the large-format AR-10-type or LR-308 platform typically chambered in .308 Winchester, 7.62x51 NATO or other cartridges requiring the longer magazine format.
Be aware that these receiver platforms are not standardized like the AR-15/M16 platform for which most parts are cross-compatible. Before ordering accessories and parts for your large-format rifle, make sure the parts are compatible with your particular platform. This bolt carrier is compatible only with the DPMS family of AR-10 products.
With the Armalite/Rock River family of large-frame receivers, this carrier can only be used as a complete bolt carrier assembly group with a DPMS-pattern bolt such as our .308 JP EnhancedBolt. Interchanging individual components will result in an unsafe configuration. Do Not under any circumstances mix and match components between the platforms.