SureFire Optimized Bolt Carrier Group Spring for M4/M16/AR-Variant Rifles & Carbines

SureFire Optimized Bolt Carrier Group Spring for M4/M16/AR-Variant Rifles & Carbines. 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. NOTE: Only Spring Specifications for SureFire Optimized Bolt Carrier Group Spring Only: Manufacturer: SureFire Fabric/Material: Steel Alloy Caliber: 5.56mm Gun Make: AR Platform Gun Model: M16 M4 Weight: 13.6 oz Bolt Material: Steel Alloy Carrier Material: Steel Alloy Features of SureFire Optimized Bolt Carrier Group Spring Only: Designed by firearms industry legend and M16 designer Jim Sullivan Long-stroke design delivers 60percent 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 Package Contents: SureFire Optimized Bolt Carrier Group Spring Only SureFire SF-OBC-556-SPRING: Optimized Bolt Carrier Group for M4/M16/AR-Variant Rifles & Carbines