6.5 Grendel vs. 6.5 Creedmoor: Which One's Best?

We won't keep you waiting 'til the end: 6.5 Creedmoor offers more power and better long-range accuracy than 6.5 Grendel -- but there are plenty of reasons you might still prefer 6.5 Grendel. See our detailed comparison of these two rounds to find out which one is best for you.

6.5 Grendel: What Is It?

6.5 Grendel is a long-range, short-action cartridge made specifically for the AR-15. Alexander Arms developed the round to improve upon the ballistics of the 5.56 NATO and .223 Remington cartridges, while making use of the AR's original components -- only the barrel needs to be swapped to convert the rifle from 5.56 or .223 to 6.5 Grendel.

6.5 Grendel Specifications

• Bullet Diameter: 0.264"
• Neck Diameter: 0.293"
• Base Diameter: 0.439"
• Case Length: 1.520"
• Overall Length: 2.260"
• Case Capacity: 35 Grains
• Max Pressure: 52,000 PSI (SAAMI)

6.5 Creedmoor: What is It?

6.5 Creedmoor fires the same 0.264" bullets as 6.5 Grendel, albeit with a larger cartridge packing about 50% more powder. The Creedmoor round was developed by Hornady specifically for long-range competition shooting. Given its intended purpose -- and larger casing -- the 6.5 Creedmoor was originally meant for bolt-action rifles, though it's now a favored 6.5mm cartridge for the AR-10 platform.

6.5 Creedmoor Specifications

• Bullet Diameter: 0.264"
• Neck Diameter: 0.295"
• Base Diameter: .0470"
• Case Length: 1.920"
• Overall Length: 2.825"
• Case Capacity: 52.5 Grains
• Max Pressure: 62,000 PSI (SAAMI)

Grendel vs. Creedmoor Specs

Although both Grendel and Creedmoor use the same bullets, grain weights vary between the two cartridges. Grendel typically uses lighter bullets (110 to 123 grains), while Creedmoor typically uses heavier bullets weighing 123 to 140 grains. 

Creedmoor's case length is approximately 26% longer, which accounts for its 50% greater powder capacity and 19% greater chamber pressure. Its higher case capacity and pressure allow Creedmoor to provide better long-range accuracy than Grendel, with overall better performance.

But that doesn't mean 6.5 Grendel isn't superior in other ways, and the greater performance of Creedmoor may not be significant enough to warrant also investing in its drawbacks.

Grendel vs. Creedmoor Ballistics

Let's dive into the hard data on what makes both rounds perform so well at distance. We're comparing the 6.5 Grendel's 123-grain AMAX Match load against the 6.5 Creedmoor's 120-grain ELD Match and 143-grain ELD Match loads.

Energy in Lb.-Ft. (0 to 500 Yards)

Here we can see 6.5 Creedmoor's 120- and 143-grain loads produce 20% and 21% more muzzle energy than Grendel's 123-grain load.

The Grendel's 123-grain load retains 48% of its muzzle velocity at 500 yards. Creedmoor's 120-grain load retains 46% of muzzle velocity at 500 yards, and its 143-grain load retains 56% of its muzzle velocity.

The Grendel's and Creedmoor's shared use of the same 0.264" bullets means that ballistic coefficients will be nearly identical. This is why Grendel and Creedmoor both retain roughly the same percentage of muzzle energy downrange.

Bullet Drop in Inches (0 to 500 Yards)

Combining both Creedmoor loads, we get an average bullet drop of 43" at 500 yards. That's approximately 18% less bullet drop than Grendel's 123-grain load.

Wind Drift in Inches (0 to 500 Yards)

NOTE: These data are collected assuming a 10 MPH crosswind for all three rounds.

Despite Creedmoor's higher muzzle velocity, its 120-grain load closely matches the wind drift of Grendel's 123-grain load. Meanwhile, Creedmoor's heavier 143-grain suffers approximately 25% less wind drift than Grendel at 500 yards.

Creedmoor: About 20% "Ballistically Better"

At greater distances, you can expect 6.5 Creedmoor to generally provide 20% better performance than 6.5 Grendel. That means 20% less bullet drop, 20% more energy downrange, and 20% less wind drift. Keep in mind that this only applies when shooting at distances of 500 yards and beyond, and you'll have to chamber Creedmoor's heavier loads -- which provide higher ballistic coefficients -- to truly maximize its performance over 6.5 Grendel.

Grendel vs. Creedmoor Ballistic Coefficients

Ballistic coefficient, or BC, measures a rounds ability to overcome air resistance in flight (learn more about it here). The higher the number, the less drag the bullet experiences in flight, which translates into less wind drift, more retained velocity, and less bullet drop. These are the ballistic coefficients for 6.5 Grendel's and 6.5 Creedmoor's more popular loads:

Grendel Loads

• Hornady 123-grain ELD: .506 BC
• Alexander 123-grain HPBT: .527 BC
• Federal 130-grain ELD: .530 BC

Creedmoor Loads

• Federal 130-grain Edge TRL: .545 BC
• Hornady 140-grain A-MAX: .585 BC
• Berger 140-grain Hybrid: .607 BC

Here we see Creedmoor's 130-grain load manages to eke out a ballistic coefficient that's about 3% greater than Grendel's 130-grain load. Not a huge difference in performance. It's also important to keep in mind that a ballistic coefficient greater than 0.5 is considered quite high. In other words, both rounds will provide high accuracy, with minimal wind drift and bullet drop, when shooting long-range.

Grendel vs. Creedmoor Max Range

The end-all-be-all of comparing these two rounds: Which one can reach out and ring steel (or take game) the furthest? Obviously, Creedmoor wins in this case -- but not by much. 

For target shooting, Creedmoor's effective range is 1,000 yards. Experienced hunters with the courage to take the shot can effectively take game at 600 yards.

Grendel's max effective range is 800 yards. Hunters can expect to snag game at 400 to 500 yards with this cartridge. 

Grendel v. Creedmoor: AR-15 or AR-10?

By now you may be thinking, "Well, of course I'm going to go with Creedmoor over Grendel!" 

Except you must also consider the platform you prefer to build (or buy, if you don't want to be awesome and put together your own rifle). 

Picking 6.5 Grendel means you're building what is essentially a standard AR-15 -- affordable and easy to put together. If you opt for chambering 6.5 Creedmoor, you're going to need to build an AR-10. This can significantly increase costs and reduce the availability of parts to customize your rifle.

Q: Which rifle is better?

A: That depends on what you think "better" means. If you prefer an overall less expensive rifle that also affords greater customization and parts availability, the 6.5 Grendel AR-15 is the clear winner. You can also convert any existing AR-15 to chamber 6.5 Grendel simply by swapping the barrel.

If you want to squeeze out every last yard of accuracy by building a heavy bench rifle -- and if cost is no concern to you -- the 6.5 Creedmoor AR-10 is the rifle of choice.

Q: What about weight?

A: The average AR-15 (including one chambered in Grendel) weighs around 6.5 pounds. Considering Grendel requires a longer barrel than the average 16", you can assume your rifle will weigh around 7 to 7.5 pounds without optics. 

The average AR-10 rifle around 10 pounds. To maximize Creedmoor's velocity, it also requires a barrel that's longer than the average .308 barrel. So add some weight here, too, bringing it to about 11 to 12 pounds.

6.5 Grendel vs. 6.5 Creedmoor Barrel Length

Speaking of barrel length -- let's dive into one of the many reasons why, in spite of its slightly lesser performance, 6.5 Grendel might still be the better choice than 6.5 Creedmoor.

6.5 Grendel

When they developed the round, Alexander Arms gave a pretty clear answer on what barrel length 6.5 Grendel needs to perform: 20 inches. To prove this, JP Rifles conducted some tests with two Grendel barrels, one measuring 18", and one measuring 22". Here's the velocity data they collected:

Jumping from an 18" barrel up to a 22" barrel only yields an extra 7.6% or so in velocity. The heavier 129-grain SST load only gains 2.4% more velocity by adding 4" of barrel. Splitting the difference in barrel length, it's easy to see a 20" barrel is ideal for 6.5 Grendel.

6.5 Creedmoor

Many shooters claim that 6.5 Creedmoor requires a 24" barrel to produce good velocities. 

But testing conducted by Rifle Shooter seems to indicate that's not true. They tested this claim by starting with a 27" barrel, measuring the muzzle velocities of 120- and 142-grain loads, then cutting 1" off the barrel and measuring again. 

Here's the data they obtained:

We can see that when dropping the Creedmoor's barrel length from 27" to just 16", the 120-grain load only lost 8% of its muzzle velocity. The 142-grain load only lost 6% of its muzzle velocity.

When sticking with a 20" barrel, the amount of muzzle velocity lost is arguably negligible: Just 4.8% for the 120-grain load, and 2% for the 142-grain load.

So, it can be argued that a 20" barrel is optimal for 6.5 Creedmoor, especially if you're trying to balance performance with weight and overall rifle length.

6.5 Grendel vs. 6.5 Creedmoor Barrel Life

On the topic of barrels, let's look at barrel life expectancy. These 6.5mm loads run hot and fast. If you're chambering either round in a semiautomatic action (like the AR-15 or AR-10) then it is possible to shoot out the barrel on both 6.5 Grendel and 6.5 Creedmoor.

The Grendel manages about 5,000 rounds of barrel life. The Creedmoor manages 2,000 to 3,000 rounds.

Grendel vs. Creedmoor Magazine Compatibility

If you're chambering either round in a bolt-action chassis, you'll be purchasing custom magazines.

But if you're chambering Grendel or Creedmoor in the AR platform, know that one has an advantage when it comes to magazine compatibility.

The Creedmoor gets a leg up over Grendel, since it uses regular .308/AR-10 magazines. The Grendel cartridge suffers from problems with feeding and chambering when 5.56/.223 magazines are used. It requires a different follower and spring, so Grendel magazines have to be specially made and usually cost more.

Grendel vs. Creedmoor Ammo Availability/Cost

This is an easy comparison: Creedmoor ammo costs more. 6.5 Crendel match loads can be bought for around $1.00 to $1.25 per round, while Creedmoor match loads typically cost $1.50 to $1.75 per round.

In other words, Creedmoor ammo costs about 50% more than Grendel ammo.

Receivers, Bolts, and Parts Kits

This comparison again covers the AR platforms. Like we mentioned earlier, the 6.5 Grendel gets the upper hand, here.

Q: What AR parts do Grendel and Creedmoor require?

If you opt for a Grendel build, you'll be buying an AR-15 upper and lower receiver, as well as an AR-15 lower parts kit and bolt carrier. The 5.56/.223 barrel and extension get swapped for a Grendel barrel and extension. Gas tubes and gas system lengths are interchangeable.

If you build a Creedmoor rifle, you'll be sticking with the AR-10 upper and lower receivers. The AR-10 also uses an AR-15 lower parts kit, but the 6.5 Creedmoor requires the AR-10 bolt carrier paired with a modified 6.5mm "high-pressure" bolt. The .308 barrel extension get swapped the 6.5mm barrel and extension.

AR-15 and .308 80% lowers can be used to complete these builds.

Q: Can I use a regular .308 AR bolt on my Creedmoor rifle?

A: No. The Creedmoor produces higher chamber pressures than .308 Winchester. Using a factory .308 bolt and firing pin will likely result in pierced primers and issues with functionality. The gas rings on the bolt may also fail early. An "HP" or high-pressure bolt and firing pin are recommended. A regular .308 bolt carrier is used with the "HP" 6.5 CM bolt. Our 6.5 Creedmoor AR kits come with HP bolts and pins to accommodate the round's higher pressure.

Q: What about an AR-15 bolt on a 6.5 Grendel rifle?

A: The same issues apply here, too. While the AR-15 carrier is used for Grendel builds, a Grendel-specific bolt is required to accommodate the higher pressures produced in the chamber.

Grendel vs. Creedmoor Recap

There's a ton of info to consider when it comes to 6.5 Grendel and 6.5 Creedmoor, especially for the AR platforms. Here are the big things to remember if you choose to build one or the other:

• Both cartridges are 6.5mm and use .264" bullets.
• Grendel's max effective range is 800 yards.
• Creedmoor's max effective range is 1.000 yards.
• Both 6.5mm rounds perform best with a 20" barrel.
• The Grendel uses the AR-15 (.223) rifle platform.
• The Creedmoor uses the LR-308 (.308) platform.