SureFire SF-OBC-556 Optimized Bolt Carrier Group Optimized Bolt Carrier Group for M4/M16/AR-Variant Rifles & Carbines
Double Down on Reliability. Invented by Jim Sullivan, one of the original designers of the M16, the SureFire Optimized Bolt Carrier (OBC) doubles the reliability of any M4/M16/AR variant weapon system during suppressed and suppressed firing. Its patented design allows more time for reliable feeding of ammunition from the magazine and nearly eliminating bolt-over-base malfunctions. The OBC also delays unlocking of the bolt during the firing sequence, which allows expanding gases more time to exit the bore, in turn reducing back-pressure gases exiting the upper receiver group. Additionally, the neutrally balanced counterweight improves carrier and barrel extension lock-up, nearly eliminating bolt bounce. The OBC reduces felt recoil for better target tracking and greater weapon control when firing. Coated with an advanced anti-friction coating, the OBC resists friction during use and makes cleaning easy.
Designed by firearms industry legend and M16 designer Jim Sullivan
Long-stroke design delivers 60% more travel beyond the magazine, increasing magazine feed time and reducing the chance of bolt-over-base malfunctions
Dual-spring dwell weight significantly delays bolt carrier direction-change for increased reliability
Improved cam path delays bolt unlocking for a 15% decrease in chamber pressure before unlocking
Self-lubricating, Diamond-Like Carbon (DLC) and S-Line coatings reduce friction for consistent, dependable operation in the most adverse conditions
Mil-Spec bolt proof-tested and magnetic particle-inspected to meet the highest standards
- SureFireÕs next-generation bolt carrier group, optimized for 5.56 mm/.223 caliber rifles and carbines
- Long-stroke design increases reliability when firing suppressed or unsuppressed
- Includes optimized bolt carrier, buffer spring and long-stroke, H-weight buffer
