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.
It also features forward assist serrations for receivers with forward assist, and it also works with receivers without it.
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)
Pros
- Affordable
- Smooth surface
- Great design
- HPT and MPI tested
- O-Ring
Cons
- Not much
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 MPI tested and fully heat treated Mil-Spec bolt carrier group. It features 45 degree chamfered bolt lug to increase service life even for the highest pressure rounds.
The gas keys use Grade 8 fasteners and they are fully staked for long period of use.
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)
Pros
- Affordable
- Smooth surface
- Great design
- HPT and MPI tested
- O-Ring
Cons
- Slightly pricey
- Heavier than others
JP Enterprises LMOS 6.5 BCG - Lowest Weight
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)
Pros
- Affordable
- Smooth surface
- Great design
- HPT and MPI tested
- O-Ring
Cons
- Pricey
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)
Pros
- Great price point
- Nothing fancy
- HPT and MPI tested
Cons
- Not much
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?
Overall, 6.5 Grendel is a much more effective hunting round for the AR 15 platform. Some call it the "Fatter 5.56". Most 6.5 Grendel ammo range between 90 - 130 grain bullet weight, and it packs more 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)
Other than the dimensional differences, the 6.5 Grendel has the edge in terms of maintaining high kinetic energy at all ranges while the standard 5.56's ballistic trajectory can stay fairly flat (Lacks energy)
With all things considered, the 6.5 Grendel is more powerful and less than a standard 308 round.
The best part is that the overall AR15 platform doesn't change, only the barrel and BCG need to be changed while still using the same lower receiver.
As the content creator of badassoptic.com, My background in the firearms industry and shooting sports gives me the experience to recommend tried and true products and keep away subpar ones.