NBS AR-15 .223/5.56 Bolt Carrier Group – Phosphate - 51108
Only 5 left in stock
The NBS 5.56 Bolt Carrier Group for AR-15 rifles is made from high quality materials with quality assurance measures like high pressure testing and magnetic particle inspecting. The bolt assembly is machined from 9310 steel and tested to ensure it can withstand thousands of high-pressure rounds. The Carrier assembly is machined from 8620 steel and the entire BCG is magnetic particle inspected to ensure every dimension is as precise at can be. The Manganese Phosphate coating on this AR-15 bolt carrier group will increase in lubricity as it absorbs oil and combines with the natural lubricity of carbon to ensure your rifle will run reliably.
Features:
- Compatible with 5.56 NATO, .223, and .300 BLK
- M16 cut and full auto rated
- 8620 steel carrier
- 9310 steel bolt
- MPI and HPT
- Manganese Phosphate coating
- Properly staked gas key
- Chrome lined gas key and firing pin channel
- Shot peened bolt face
- Black O-ring extractor insert
NBS — Our In-House Brand for Builders Who Demand Reliable Performance and Real Value.
Designed for builders who demand reliable performance and real value without unnecessary hype or inflated pricing. NBS stands for "No Bullshit."
Built on Strong Industry Partnerships
Through the strong partnerships AR15Discounts has built with trusted suppliers and vendors, we regularly gain access to premium components often manufactured by or for leading industry names. By purchasing these in volume, we bring them to you under the NBS label, ensuring proven quality reaches your build at a fair price, without the added cost of extensive marketing.
Quality You Can Trust
Every NBS product is specified to the exacting standards we apply to our own rifles. Each component features precision CNC machining, American-made key components where it counts, robust materials, dependable steels, and durable finishes engineered for long-term reliability. These items are either sourced from reputable OEMs or carefully assembled in-house using established name-brand elements, maintaining consistent excellence throughout the lineup.
Complete Solutions for Serious Builders
From stripped and complete uppers to bolt carrier groups, handguards, lower parts kits, and beyond, NBS provides a unified, affordable selection that allows you to complete confident, high-performing builds.
Backed by a Limited Lifetime Warranty
All NBS products come with our Limited Lifetime Warranty for the original owner, covering defects in materials and workmanship. AR15Discounts stands firmly behind these parts because, as shooters ourselves, we use and trust them, delivering honest value and gear you can rely on.
| Weight | 16 oz |
|---|---|
| Bolt Material | 9310 Steel |
| Cartridge Compatibility | .223/5.56 NATO/.300 BLK |
| Finish | Mag Phosphate |
| Carrier Profile | M16 |
| High Pressure Tested | Untested |
| Magnetic Particle Inspected | Magnetic Partical Inspected |
| Platform | AR-15 |
| Bolt Finish | Mag Phosphate |
| MPN | 51108 |
| UPC | 999997835 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
Customer Reviews
- Reviews
- Questions
- build quality
- Operation
- discounts
US
Excellent bolt carrier groups
As with anything I purchase through ar15 discounts, I'm very pleased
USExcellent bolt carrier
easy to install and flawless operation.
USGood quality
Works fine. Good build quality.
United StatesOver-priced even now
Might have gotten a lemon but BCG did not function in any rifle. The price may be right but spend a little more and get a better product. As usual AR discounts were great to deal with. Product 1/10 AR Discounts 10/10.
