5.56 Left Handed M16 Bolt Carrier Group (BCG) – Lefty AR-15 Nitride
Designed specifically for left-handed shooters, the 5.56 Left Handed M16 Bolt Carrier Group from Mid State Firearms delivers reliable performance with proper left-side ejection. Finished in a durable black nitride (QPQ) coating, this lefty AR-15 BCG offers smooth cycling, corrosion resistance, and easy cleaning for duty, range, or builder rifles.
Unlike standard right-hand components, this bolt carrier group is purpose-built for left-hand ejecting AR-15 upper receivers, ensuring correct extractor and ejector geometry. The M16 / full-auto carrier profile provides added mass for consistent operation across a wide range of 5.56 NATO and .223 ammunition.
Whether you’re finishing a dedicated left-hand AR build or upgrading an existing rifle, this BCG is a critical component you can rely on.
Key Features
- Left-handed 5.56 / .223 bolt carrier group
- Designed for left-hand ejecting AR-15 uppers
- M16 / full-auto carrier profile
- Black nitride (QPQ) finish for durability and corrosion resistance
- Properly staked gas key
- Smooth cycling and easy maintenance
Specifications
- Caliber: 5.56 NATO / .223 Remington
- Handedness: Left
- Carrier Style: M16 / Full Auto
- Finish: Black Nitride
- Compatibility: Left-hand AR-15 uppers only
Note: This bolt carrier group will not function in standard right-hand AR-15 upper receivers.
Complete Your Left-Hand Build
- View all Left Handed BCGs:
https://midstatefirearms.com/product-category/ar15-ar10/upper-receivers-parts/bolt-carrier-groups/left-handed-bcgs/ - Left Handed Builder Bundle (Upper + BCG):
https://midstatefirearms.com/product/left-handed-builder-bundle-receiver-and-bcg/ - Left Handed Builder Bundle with Nitride BCG:
https://midstatefirearms.com/product/ar15-left-handed-builder-bundle-receiver-and-nitride-bcg-combo/
Built for left-handed shooters who want proper ejection, smoother operation, and dependable performance — this Left Handed 5.56 M16 BCG is a must-have for any lefty AR-15 setup.
-300x300.jpg "Left Hand Nickel Boron BCG M16 / Ar15 Bolt Carrier Group, photo")
-300x300.png "15' Gen1 Free Float Quad Rail, photo")
sound of freedom – This was a great set up. I loved being able to customize the set up. Only issue I had was my own fault as a newb to building these. I used a heavy barrel in a slim hand guard. It makes adding attachments tough with clearances. Hoping someday to also get an AR10 from here.