SureFire Optimized Bolt Carrier Group Spring for M4/M16/AR-Variant Rifles & Carbines SF-OBC-556-SPRING. Its patented design allows more time for reliable feeding of ammunition from the magazine and nearly eliminating bolt-over-base malfunctions. The...
SureFire Optimized Bolt Carrier Group Spring for M4/M16/AR-Variant Rifles & Carbines SF-OBC-556-SPRING. Its patented design allows more time for reliable feeding of ammunition from the magazine and nearly eliminating bolt-over-base malfunctions. The...