Failzero Fail Zero Bolt Carrier Group BCG .450 Bushmaster Ar-15. The FAILZeroBCG is a .450-caliber bolt carrier group that reliably cycles .450-caliber ammunition without fail or damage. This FAILZeroBCG is purpose-built and built to last. The...
Failzero Fail Zero Bolt Carrier Group BCG .450 Bushmaster Ar-15. The FAILZeroBCG is a .450-caliber bolt carrier group that reliably cycles .450-caliber ammunition without fail or damage. This FAILZeroBCG is purpose-built and built to last. The...