The 6mm ARC vs 6.5 Grendel is worthy of debate since both cartridges have the same parent cartridge.
Both were designed for the AR-15 platform for similar reasons, so which one does the job the best?
Honestly, it boils down to your intended purpose.
6.5 Grendel vs. 6mm ARC
These two rounds are incredibly similar, so does it matter which one you choose?
We say yes!
However, each caliber has its purpose, so we will break down which caliber is best overall, but we will also give you the circumstances when one is more beneficial than the other.
Cartridge Specs
The 6mm ARC and the 6.5 Grendel originate from the .220 Russian, so there is very little difference between them.
Even experienced shooters will have difficulty telling the rounds apart at a glance.
The bullet diameters differ by only 0.021”, with the 6.5 Grendel being 0.264” and the 6mm ARC 0.243”.
Rim diameter is even closer with only 0.001” difference. The 6.5 Grendel is 0.44” in diameter, whereas the 6mm ARC is 0.441”.
The 6mm ARC case is slightly shorter: 1.49”, compared to 1.52” for the 6.5 Grendel case.
The 6.5 Grendel has a broader range of bullet weights, ranging from 90 grains to 130 grains. In contrast, the 6mm ARC is offered in 58 to 108 grains.
| Category | 6mm ARC | 6.5 Grendel |
|---|---|---|
| Parent Case | 5.6Ă—39mm | 6.5mm PPC |
| Bullet Diameter | 0.243 in | 0.264 in |
| Neck Diameter | 0.274 in | 0.293 in |
| Base Diameter | 0.441 in | 0.439 in |
| Case Length | 1.49 in | 1.52 in |
| Overall Length | 2.26 in | 2.26 in |
| Case Capacity | 34 grains | 35 grains |
| Max Pressure (SAAMI) | 52,000 psi | 52,000 psi |
The overall length of the rounds is the same at 2.26 inches.
6.5 Grendel vs. 6mm ARC Recoil
From looking at the rounds, you could guess they have very similar recoil.
Felt recoil depends on many factors, including the gun’s weight, bullet weight, and shooter.
Neither round is known for high felt recoil, but the 6mm ARC doesn’t pack as much punch as the 6.5 Grendel, which has 9-foot-pounds of recoil due to the lower case capacity.
This is because it holds slightly less powder and fires smaller projectiles.
The 6mm ARC has a slight advantage for recoil and is an excellent choice to introduce individuals to firearms apprehensive of guns because of recoil concerns.
Trajectory
The trajectory is the bullet’s path to the target.
As shooters, we prefer a flat-shooting round over ammunition that requires us to adjust for bullet drop.
That’s why 6mm bullets are so popular amongst medium-range to long-range shooters. They’re known to be flat-shooting bullets.
The 6mm ARC is a more aerodynamic bullet than the 6.5 Grendel. At 400 yards, it has an average bullet drop of 22.2 inches.
The bullet drop for the 6.5 Grendel is slightly greater because it’s a larger bullet. However, 25.3 inches of drop at 400yds is by no means terrible.
Therefore, the 6mm ARC has a flatter trajectory by 3.1" at 400yds.
The bullet drop difference will be exponentially more significant as we extend the distance. However, both rounds are excellent long-range rounds.
By a narrow margin, the winner is the 6mm ARC.
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