Mean Arms Bearing Delay 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.

All threaded for a 1/2-28 muzzle device. No 9mm-specific buffer needed it is designed to work with standard AR-15 buffers.

The Bearing Delay Upper Receiver is the unique ball bearing bolt carrier group (BCG). The ball bearings interface with corresponding features in the barrel extension and provide the lockup in battery and the delay after firing. The system can be tuned by replacing the Lifter to change the angle of the surfaces that push the bearings from the inside of the BCG. The bolt face includes our unique center ejector to provide the most consistent ejection of any 9mm AR on the market. The firing pin passes through the ejector.

Take all the benefits of roller delay: reliability, durability, low recoil and combine with the familiarity of the AR-15 platform. Rollers are obsolete. Each of the ball bearings has the same contact surface area of the original MP5 roller. So with the 3 bearings, we have 50% more contact surface area than a traditional roller delay. This means that even with the higher pressures of modern ammunition, the Bearing Delay system has greater durability than any roller delay.

If you elect to use MEAN Arms Endomags (Ejectorless), the Bearing Delay Upper Receiver is compatible with milspec lower receivers OR you can use dedicated pistol magazine lower receivers. Most pistol magazine lower receivers will need to have the stationary ejector removed to be compatible with the Bearing Delay system.

Each Bearing Delay Upper Receiver includes 2 Ejectorless Endomags.

Specifications:

• Caliber: 9×19mm Parabellum
• Compatible with both milspec AR-15 and dedicated pistol-magazine lower receivers
• Works with standard AR-15 buffers
• 5 available barrel lengths: 11", 16"
• Weight of entire Upper (BCG alone is just under 11oz)
  • 11" is 3.23 lbs
  • 16" is 3.72 lbs
• Each Bearing Delay Upper Receiver includes:
  • Fully tunable ball bearing bolt carrier group
  • MA Upper Receiver - slick side billet machined aluminum upper receiver
  • MA Handguard - free float hybrid metal/polymer design. Internal size: ~1.375"
  • MA Charging Handle - new ambidextrous design
  • MA Muzzle Device - exclusive machined design reduces recoil and muzzle flash
• Also included with the purchase of the Bearing Delay Upper Receiver:
  • 1 additional Lifter for tuning the system (2 total included)
  • 2 Ejectorless EndoMags (PMAGs NOT included)