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JP VMOS™ Bolt Carrier Group with JP EnhancedBolt
   Large Frame (.308)
   Standard Version

Like our small-frame JPBC-1, this carrier is the ultimate game gun operating system, now available for your heavy metal rig. The JPBC-8 offers an extremely light recoil impulse with minimal sacrifice in reliability.

The JPBC-8 also pulls from the advances of our JPBC-7 VMOS™ carrier. This standard version of the aluminum large-frame VMOS carrier includes three steel weights, two of which can be exchanged for heavier tungsten weights.

This carrier group includes our proprietary bolt design, the JP EnhancedBolt™. Superior in every way to standard bolts, it's manufactured from SAE 9310, providing drastically extended lifespan with design improvements that ensure superior function.

The EnhancedBolt™ is compatible with the JP LRP-07™ and the DPMS LR-308 platforms (or clones thereof) only and cannot be used to replace bolts in the Armalite AR-10 platform (or clones thereof).

Package includes carrier, bolt assembly, cam pin, titanium firing pin, firing pin retainer pin and instruction sheet.

Weight: 10.1 oz.

Features (bolt carrier):

  • Enhanced tunability of operating system
  • Faster sight recovery and follow-up shots
  • Increased bearing surfaces for slower wear and longer component life
  • Longer Mil-spec cocking pad for optimal reliability
  • Included Enhanced Gas Ring provides perfect bore-to-gas seal fitment and minimized friction/carrier wear
  • Included titanium firing pin eliminates possibility of slamfires at higher bolt velocities
  • Full-length forward assist serrations

Features (bolt):

  • SAE 9310 steel construction for superior resiliency and extended lifespan
  • DLC coating provides extreme surface hardness and lubricity while maintaining a ductile core
  • Near frictionless surface finish
  • Fully compatible with Mil-spec sub-components
  • Improved lug geometry for reduced wear and easier locking/unlocking
  • Enhanced Ejector mitigates head case extrusions and reduces brass smear
  • Enhanced Extractor optimizes extraction function and eliminates common ejection failures
  • Enhanced Gas Ring reduces internal friction and carrier wear while maintaining near indefinite gas seal


The JP .308HP bolt does not allow for the use of excessive pressure, overloaded ammunition that exceeds SAAMI specifications. When evaluating new ammunition, always start on the low- to mid-range of any published load data and work up. A good indicator of working pressure is the primer retention on the subsequent loading of a case. A noticeable loss of primer pocket tension indicates that your ammunition has excessive pressure and has overworked the case.


  • 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 should not be run stripped (i.e., without any masses).
  • This carrier will not cycle with a standard buffer retainer plunger installed and should be used only with a Silent Captured Spring.
  • Because our Law Tactical Folder Silent Captured Springs require use of a buffer retainer plunger to work, they are also not compatible with this VMOS™ bolt carrier.

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 group 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.


This carrier is not recommended for use with gas systems shorter than mid-length for longest service life. Use with carbine or shorter gas systems may result in gas erosion in the tail stock area and subsequent leakage and reduced service life.

To help avoid the instance of slamfires, this bolt carrier comes packaged with a titanium firing pin. We strong encourage use of a titanium firing pin with this carrier to ensure safety.

Use of a hammer with a radiused leading edge such as our JP Speed Hammer is recommended.

Use with a Silent Captured Spring assembled with a lighter weight spring will produce superior results.


Patents: 10,184,739

Price: $495.00