300 Blackout vs 6.5 Grendel – What Ammo Gets The Approval?

300 blackout vs 6.5 grendel
Alfred Mendoza
Weighing your options in choosing between the 6.5 Grendel vs 300 Blackout could be a little tough to handle. Both Grendel 6.5 and 300 BLK are hot stuff in the shooting community, considering how well they perform when it comes to trajectory, weight, and compatibility. But which one is better in the shooting range?
The 6.5 Grendel is an intermediate high-accuracy cartridge intended for AR-15 rifles, while the 300 Blackout, also an intermediate cartridge, was intended for M14 carbine and AR-15 rifles.

Specification Chart

300 Blackout

  • Brand: Advanced Armament Corporation (AAC)
  • Model: 300 Blackout
  • Bullet Size: 2.26 inches
  • Bullet Diameter: 0.308 inches
  • Shell Case Length: 1.368 inches
  • Energy (per 200 yards): 824 ft⋅lbs
  • Velocity (per 200 yards): 1872 ft/s
  • Muzzle Energy: 1,360 ft⋅lbs
  • Muzzle Velocity: 2,215 ft/s

6.5 Grendel

  • Brand: Alexander Arms
  • Model: 6.5 Grendel
  • Bullet Size: 2.26 inches
  • Bullet Diameter: 0.264 in
  • Shell Case Length: 1.52 in
  • Energy (per 200 yards): 1,383 ft-lbs
  • Velocity (per 200 yards): 2,278 ft/s
  • Muzzle Energy: 1,658 ft-lbs
  • Muzzle Velocity: 2,880 ft/s

In-Depth Comparison


Availability-wise, the 6.5 Grendel is easier to find in the market because of its versatility. And even if we were to talk about their costs, the Grendel is more economical compared to the 300 Blackout, which could be considered as a top-selling point for the 6.5 Grendel. With this, the 6.5 Grendel takes its first win for being more cost-friendly over the 300 Blackout.

6.5 Grendel vs 300 Trajectory

In this category, the 6.5 Grendel stomps over the 300 BLK because it has a flatter trajectory and has a longer projectile.

The 300 Blackout usually drops at the past 300 yards while the 6.5 Grendel stays longer until it drops past 600 yards. Because of this, the 6.5 Grendel takes the lead in having a flatter trajectory than the 300 Blackout.

Related Article: Blackout 300 1-7 versus 1-8 Twist Rate

6.5 grendel trajectory

Long Distance Shooting

For hunting in the AR15, 6.5 Grendel could be a superstar. And since it has a better trajectory than a 300 BLK, it works better for long-range shooting, too. Do note that 300 BLK only could be on par with the 6.5 Grendel when used with suppressors. Grendel does well even in short barrels—even as short as 12 inches for hunting out to 300 yards. The 360 Blackout has an effective range of over 400 yards while 6.5 Grendel could even go past 800-1000 yards.

Loading Type - Blackout 300 or 6.5?

Both the 6.5 Grendel and the 300 BLK AAC are handloading optimal. Although the 300 Blackout one can carry multiple loads in different mags, one should be careful in loading it into a 5.56mm AR rifle. Some unforeseen cases may result in severe injuries and kaboom of rifles if one would accidentally load it to a 5.56 AR. However, the 6.5 Grendel is standardized round, with high-quality Lapua brass and factory-loaded ammo. Since Grendel optimizes the AR platform, it beats the 300 AAC in this category.

Read: Recommended 300 Blackout (SBR) Suppressors

Bullet Weights

6.5 grendel bullet weight

While there may be a relatively large selection of bullet weights/loads available for both ammo, 6.5 Grendel has lighter bullet weights compared to 300 Blackout.

The 6.5. Grendel has five bullet types ranging from 90 gr to 130 gr, while 308 Blackout offers 78 gr to 225 gr bullet types, which are denser than Grendel’s. Having lighter bullets means flatter trajectory. Flat trajectory means longer range capability. With this, the 6.5 Grendel is of advantage.

Grendel 6.5 & 300 Bullet Energy

With the given bullet weights above, we can safely claim that 300 Blackout has heavier bullets. And heavier bullets always carry more energy. And with a given caliber, they will also have longer shanks, which can maintain momentum for deeper penetration. At this point, the 300 Blackout tops the 6.5 Grendel in this most argued combat 300 Blackout vs 6.5 Grendel.

Great alternatives: Winchester 308 and 458 SOCOM

Grendel 6.5 Pros & Cons



300 Blackout Pros & Cons



6.5 Grendel & Blackout 300? The Better Ammo is...?

Our team decided that in comparing the 6.5 Grendel vs 300 Blackout – the better ammo is the 6.5 Grendel because it outperforms the Blackout 300 in affordability, trajectory, loading types, and distance shooting and has high BC. Although the 300 BLK is also a great round, whatever you choose would still make your hunting fun.

Still looking for other ammo? Check out 6.5 Creedmoor and 224 Valkyrie comparison.

6.5 Grendel

Our #1 Recommendation

6.5 Grendel

1 thought on “300 Blackout vs 6.5 Grendel – What Ammo Gets The Approval?”

Leave a Comment

Your email address will not be published. Required fields are marked *