4 Best 6.5 Grendel BCG [Updated 2024]

Here are the 4 best 6.5 Grendel BCG for custom AR15 builds. The 6.5 Grendel BCG itself is has the same functionality as a 5.56 BCG besides the bolt.

There are many options out there, and we have narrowed down to the ones that are most purchased to save you time.

Check out what we have here:

To finish your lower receiver build, go here

Best Lightweight 6.5 Grendel BCG

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Aero Precision 6.5 Grendel BCG - Best Overall

Aero Precision makes great AR15 parts and accessories from top to bottom. Their new 6.5 Grendel BCG is machined from 8620 steel (MPI tested) with nitride finish for reduced bolt travel friction and increased service life.

The M16-cut bolt carriers are virtually indestructible. Moreover, they've been treated with a black nitride finish, reducing the need for frequent cleaning and lubrication compared to untreated bolts.

The 6.5 Grendel bolt, forged from Carpenter 9310 tool steel, offers long-lasting performance. This option is ideal for various users, especially those expecting high round counts in competitions or precision shooting. It's particularly suited for AR builders.

The Aero Precision 6.5 Grendel Bolt Carrier Group in Black Nitride is an excellent choice for constructing a precision AR capable of withstanding rigorous use in high-round-count scenarios or fast-paced competitive shooting.

Bolt Material - 158 tool steel

BCG Material - 8620 steel

Weight - 11.52 oz

Coating - Black Nitride

Bolt Type - M16 Full Auto (No full auto without full auto lower)

Also check out Aero Precision M4E1 complete upper with 6.5 Grendel BCG here

Faxon 6.5 BCG - Best For Recoil Reduction

This is a Type II bolt carrier group that has undergone MPI testing and full heat treatment, adhering to Mil-Spec standards. Notably, it features a 45-degree chamfered bolt lug, significantly extending its service life, even when used with high-pressure rounds.

These enhancements involve the use of 9310 tool steel for the bolt, along with nitriding applied to the assembly. This process increases surface hardness, reduces friction, and provides superior corrosion resistance compared to conventional chrome and phosphated bolt carrier groups. To ensure impeccable quality, all bolts undergo rigorous MPI testing to detect and eliminate any defects.

The chamfered bolt lugs, angled at 45 degrees, deliver reliable performance, even when handling high-pressure hand loads and swift, lightweight actions.

Bolt Material - 9310 tool steel

BCG Material - 8620 steel

Weight - 12.5 oz

Coating - Salt Bath Nitrided

Bolt Type - M16 Full Auto (No full auto without full auto lower)

JP Enterprises LMOS 6.5 BCG - Lowest Weight

The JP LMOS carriers are crafted from stainless steel and feature a QPQ finish, which is smoother and more refined than a phosphated carrier. There are numerous dependable adjustable gas systems available; for instance, the Syrac gas block functions exceptionally well, with its adjusting screw securely held in place by a detent.

For added durability, you can pin the Syrac block, just like any other low-profile gas block. The LMOS is approximately 2 ounces lighter than a semi-automatic carrier, which means your choice of buffer and spring becomes more critical in ensuring the gun's reliability.

I believe it's quite feasible to achieve "combat reliability" with a firearm equipped with the LMOS system.

Bolt Material - 9310 tool steel

BCG Material - 8620 steel

Weight - 8.8 oz

Coating - Stainless Steel

Bolt Type - M16 Full Auto (No full auto without full auto lower)

TRYBE Defense 6.5 BCG - Best For The Money

Bolt Material - 158 tool steel

BCG Material - 8620 steel

Weight - 11.3 oz

Coating - Black Nitride

Bolt Type - M16 Full Auto (No full auto without full auto lower)

FAQ

Differences Between 5.56 vs 6.5 BCG

The difference between 5.56 and 6.5 BCG is the bolt. The bolt carrier is the same.

Differences Between Type I and II Grendel Bolt

The biggest difference between Grendel Type I vs Type II is head spacing.

Type I is known as the 7.62X39 bolt - Bolt face is 0.125"

Type II is the original Grendel, now people just call it Grendel Type II - Bolt head spacing is 0.136"

Does A 6.5 Grendel BCG Fit Inside A Standard AR15 Upper Receiver?

Yes, 6.5 Grendel BCG fit inside any standard AR15 upper receiver.

Can You Use A 556 Lower For 6.5 Grendel?

Yes, a 5.56 lower receiver works with 6.5 grendel upper (Of course, while using a 6.5 Grendel BCG)

Is Bolt Carrier Group Different Than Bolt?

Bolt Carrier Group (BCG) contains the bolt. 

This is the bolt people talk about

This is the bolt carrier group that hold the bolt, firing pin, gas key and retainer pin

When assembled, the BCG looks like this:

Why 6.5 Grendel Cartidge?

In the world of AR 15 rifles, the 6.5 Grendel stands out as a highly efficient hunting round. It's often referred to as the "Fatter 5.56" due to its effectiveness. Typically, 6.5 Grendel ammunition features bullet weights ranging from 90 to 130 grains, and it delivers greater ballistic energy.

Standard 55gr 5.56

• Bullet Diameter:0.224"
• Case Length: 1.76"
• Rim Diamenter: 0.387"
• Total Length: 2.25"
• Max Pressure: 55K PSI
• Max Range: Max effective about 450 yards
• Max Energy: 1282 ft lb (Muzzle), 750 (200 yd), 290 (500 yd)

Standard 123 gr 6.5 Grendel

• Bullet Diameter:0.264"
• Case Length: 1.52"
• Rim Diamenter: 0.441"
• Total Length: 2.26"
• Max Pressure: 52K PSI
• Max Range: Max effective up to 800 yards
• Max Energy: 1818 ft lb (Muzzle), 1376 (200 yd), 870 (500 yd)

Apart from the size differences, the 6.5 Grendel outperforms the standard 5.56 in terms of retaining high kinetic energy across all ranges. In contrast, the 5.56 has a flatter ballistic trajectory but lacks energy.

Taking everything into account, the 6.5 Grendel is more potent and smaller than a typical .308 round.

The great thing is that you don't need to modify the entire AR15 platform; only the barrel and BCG need to be swapped out, while you can still use the same lower receiver.