What types of bolt carrier groups are available?

We carry AR-15, AR-10, lightweight, and 9mm PCC bolt carrier groups in phosphate, nitride, nickel boron, and DLC finishes from top brands.

What is the difference between phosphate and nitride finishes?

Phosphate is mil-spec and rougher textured; nitride is smoother, more corrosion-resistant, and easier to clean.

Do your BCGs include MPI and HPT testing?

Yes, most of our BCGs are Magnetic Particle Inspected and High Pressure Tested for quality and durability.

Are these bolt carrier groups compatible with full-auto rifles?

Yes, most BCGs offered are full-auto rated and feature M16-profile carriers for enhanced mass and cycling.

Where are your bolt carrier groups manufactured?

All our bolt carrier groups are made in the USA by trusted manufacturers including BCM, Aero Precision, Sons of Liberty Gun Works, and others.

Bolt Carrier Groups – AR-15 & AR-10 BCGs

Bolt Parts

**Ergo AR-15 Bolt Carrier Group (AR BCG)** $165.90

**Phase5 Bolt Carrier Group Ar15 Blk** $150.00

**Phase5 Bolt Carrier Group M16 Blk** $150.00

**Kak K-spec Enh Carrier Dv Sc C&p** $103.49

**Fz M16/m4 Bolt Carrier Group** $168.90

**Fz Lightweight Bolt Carrier Group** $219.73

**Dbst Bolt Carrier Rebuild Kit** $62.16

**Daniel Defense Bolt Carrier Group 5.56** $232.14

**CMC Triggers Enchanced Bolt Carrier Group Ar15 5.56/.223/300blackout** $199.00

**Bcm Bolt Carrier Group (mpi) - Auto** $249.99

**Bad 9mm Ar15 Bolt Carrier Group Blk** $179.62

**Sons Of Liberty Gun Works Scalper Bolt Carrier Group** $205.46

**Sons Of Liberty Gun Works Bolt Carrier Group** $201.99

**Spike's M16 Bolt Carrier Group Blk** $145.79

**Spike's M16 Bolt Carrier Group Lw** $235.12

**Aero Ar9 9mm Bcg Blk Nitride** $194.02

**Aero Ar15 5.56 Pro Series Bcg Ntrd** $190.37

**Angstadt Arms Ar15 Bcg 9mm Blk** $189.29

**Angstadt Arms Ar15 Bcg 556nato Blk** $136.90

**Bad 556 Ar15 Bcg Titanium Armorti** $467.26

Bolt Carrier Groups – Upgrade Your AR with Performance-Driven BCGs

Precision. Reliability. Built for Real-World Use.

The Bolt Carrier Group (BCG) is the beating heart of your AR-15 or AR-10. Whether you’re building your first rifle, tuning a competition carbine, or replacing a worn-out unit, upgrading your BCG can dramatically improve reliability, smoothness, and overall performance.

At Mounts Plus, we offer a curated collection of high-quality bolt carrier groups from trusted manufacturers like BCM, Sons of Liberty Gun Works, CMC Triggers, Aero Precision, Spike’s Tactical, and more. From mil-spec phosphate to DLC-coated and titanium carriers, you’ll find the perfect match for your rifle and shooting style.

Why Choose Your BCG Carefully?

✅ Critical to Rifle Reliability – The BCG is the engine that cycles every round
✅ Material & Coating Matter – Chrome, nitride, nickel boron, and titanium options
✅ Full-Auto Rated Carriers – Built for long-term durability under hard use
✅ MPI/HPT Tested – Magnetic Particle Inspected and pressure-tested for strength
✅ Drop-In Fit – Compatible with most AR-15 and AR-10 platforms
✅ Made in the USA – From trusted defense and commercial manufacturers

Types of Bolt Carrier Groups We Offer

✔️ AR-15 Standard BCGs

Full-auto profile carriers
Available in phosphate, nitride, nickel boron, and DLC coatings
Ideal for most civilian builds, training rifles, or defensive setups

✔️ Lightweight BCGs

Reduced mass = lower recoil impulse
Great for competition shooters or tuned gas systems
Titanium and aluminum carrier options

✔️ 9mm & PCC Bolt Carrier Groups

Dedicated BCGs for pistol-caliber carbines (Glock mag & Colt mag variants)
Compatible with blowback 9mm uppers

✔️ .308 / AR-10 BCGs

SR-25 pattern compatible
Available in nickel boron and black nitride finishes

Brands We Trust

BCM (Bravo Company USA) – Auto-rated mil-spec phosphate BCGs
Sons of Liberty Gun Works (SOLGW) – Battle-tested performance
Aero Precision – High-value black nitride BCGs
CMC Triggers – Enhanced AR-15 carriers with polished finish
Phase 5 – AR-15 & 9mm BCGs in sleek black nitride
Spike’s Tactical – Mil-spec and lightweight bolt groups

Fitment & Compatibility

✔️ Fits all mil-spec AR-15 upper receivers
✔️ Drop-in fit for 5.56 NATO / .223 Wylde / .300 Blackout
✔️ Options available for AR-10 / SR-25 platforms
✔️ Choose from standard, suppressed-ready, or lightweight carriers
✔️ Works with carbine and mid-length gas systems

Most BCGs are ready to drop in and run — no modification needed.

What to Look for in a Bolt Carrier Group

Feature	Why It Matters
Material	8620 steel carriers, 9310 or C158 bolts = durability
Finish	Phosphate (classic), Nitride (slick), NiB (easy clean)
Gas Key Staking	Properly staked = no gas leaks
MPI / HPT Testing	Ensures part integrity under pressure
Full Auto Rated	Increased mass for smoother cycling

Frequently Asked Questions

What’s the difference between nitride and phosphate BCGs?
Phosphate is traditional and rugged. Nitride is smoother, easier to clean, and slightly more corrosion-resistant.

Do I need a full-auto rated BCG for my AR-15?
Yes — most high-quality BCGs today use an M16-style carrier for better cycling. They're legal in semi-auto ARs.

What’s MPI testing?
Magnetic Particle Inspection checks for microscopic cracks or defects — critical for long-term bolt integrity.

Can I use an AR-10 BCG in my AR-15?
No. AR-10 and AR-15 bolt carrier groups are not interchangeable due to length, bolt size, and upper geometry.

Are these BCGs made in the USA?
Yes. We source our BCGs from vetted U.S. manufacturers who stand behind their parts.

Related Products

Built to Cycle. Built to Last.

Your AR is only as good as the BCG inside it. Choose a bolt carrier group you can trust — one that won’t fail under pressure, one that feeds and extracts smoothly, and one that enhances your rifle’s accuracy and life span.

Shop premium bolt carrier groups at Mounts Plus — fast shipping, expert advice, and gear that’s built to perform.

Bolt Carrier Groups – AR-15 & AR-10 BCGs | Mounts Plus