Bearing Delay 9mm Luger Complete Upper Receiver - Bearing Delay 9mm Luger 4.5'''' Bbl Assembled Upper Receiver

The Bearing Delay Upper Receiver is a complete upper receiver system ready to be paired with the AR lower receiver of your choice. Available in 5 different barrel lengths: 4.5", 7.5", 11", 14.5", 16" - all threaded for a 1/2-28 muzzle device. No 9mm-specific buffer needed. The Bearing Delay Upper Receiver is designed to work with standard AR-15 buffers. The heart of the Bearing Delay Upper Receiver is the unique ball bearing bolt carrier group (BCG). The ball bearings interface with correspondi