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 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 Mean’s ball bearings has the same contact surface area of the original MP5 roller. So with their 3 bearings, they 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.
The ability to tune the system by swapping the Lifter means that the Bearing Delayâ„¢ system can be tuned based on ammunition type, barrel length, suppressor, or any other factor. Each Bearing Delay Upper Receiver includes two Lifters.
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.
MA Upper Receiver
The Bearing Delay Upper Receiver includes a slick side billet machined aluminum upper receiver that adheres to milspec standards. No forward assist.
MA Handguard
The new MA Handguard is a free float hybrid design including a very rigid high temperature and high strength polymer body with a metallic insert that is overmolded (permanently attached) within the handguard and threads onto the specially designed barrel nut.
Internal width (flat to flat): ~1.375"
Available in 5 lengths based on the barrel configurations of the Bearing Delay Upper Receiver.
MA Charging Handle
The MA Charging Handle is a new ambidextrous design incorporating both steel and aluminum machined components.
MA Muzzle Device
The MA Muzzle Device reduces recoil and muzzle flash. Comes with a left-hand threaded jam nut which eliminates the need for a crush washer.
SPECS
- 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: 4.5", 7.5", 11", 14.5" and 16"
- Weight of entire Upper (BCG alone is just under 11oz)
- 4.5" is 2.59 lbs
- 7.5" is 2.92 lbs
- 11" is 3.23 lbs
- 14.5" is 3.57 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
- 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)
See all of our AR15s and AR15 parts here.
Threaded Barrel Restriction:
Threaded Barrels have restricted shipping to CA.
WARNING: Lead - Discharging firearms in poorly ventilated areas, cleaning firearms, or handling ammunition may result in exposure to lead and other substances known to cause birth defects, reproductive harm, and other serious physical injury. Have adequate ventilation at all times. Wash hands thoroughly after exposure.
