308 vs 6.5 Grendel Ballistics: The Truth You Deserve To Know

6.5 grendel vs 308
Alfred Mendoza

Even for seasoned firearms enthusiasts, 6.5 Grendel vs 308 is an intense debate nobody seems to win over time. And if you are new to the “Rifle Lovers Club,” this comprehensive comparison between these in-demand cartridges may help you decide which is better for your rifle.

Let’s dive into their accuracy, weight, recoil, ballistic terminal, balance, distance, and of course, price to see which will emerge as a victor between the two ammo.

The key difference between 6.5 Grendel & 308 lies in the purpose of using either firearm. Grendel 6.5mm, unlike the 6.5 Creedmoor, is an intermediate cartridge designed exclusively for AR 15, while the 308 is for civilian hunting, target shooting, or snipers.

In 2007, the 6.5 Grendel was initially created for long-range targets, while the 308 was designed for a semi-automatic military rifle in 1952.

6.5 Grendel

  • Lighter for several pounds
  • Has low recoil
  • More aerodynamic
  • Has higher BC
  • Higher sectional density


  • Heavier and shorter
  • Available in massive quantities
  • Ideal for military use, police use, and powerful for hunting
  • Requires an extended barrel for expansion
  • Can handle larger game

How Are They Similar?

The similarities of both power ammo are too apparent that most firearms enthusiasts always compare them side by side. Well, since both bullets are great for long-range shooting like the 6.5 Creedmoor, most hunters want to know their advantages over the other. Although the Grendel is significantly lighter than the AR 10, it still uses a standard AR 15 lower, and the ballistics are similar to a 308. 

  • Works best in long-range shooting
  • Trajectory and wind drift
  • Same power for hunting
  • Can handle larger games

In-Depth Comparison


For seasoned shooters, precision matters the most. 

The 6.5 Grendel cartridge gains its velocity faster, like the spc than 308 bullets. 

The 6.5 Grendel is more aerodynamic. The 6.5 Grendel travels substantially faster than 308 at 1000 meters, although its projectile starts much slower than a 308 bullet at the muzzle. 


Although many shooters claim that the birth of 6.5 Grendel made it the best round accuracy-wise, the 308 Winchester’s legendary accuracy never faded. It’s a no brainer because so far since it’s conception, the 308 became the favorite of military and police snipers worldwide.

If you’re interested on rifles, read TC Compass vs Ruge American here


Active hunters would appreciate the lighter weight of the 6.5 Grendel, especially when hunts would only permit limited weight. It’s also a plus to carry rifles that weigh less and ammo if you’re on a long hunt. The 6.5 Grendel ammunition weighs less and requires less space than 308 ammo.

However, the difference in weight between the two ammo is just several pounds lesser. So, if you are to carry your light rifle around for hours, it is more likely that you would have less fatigue. Remember, a bullet that weighs less also means more rounds for a given load limit.


The barrel length affects balance, so it’s something that many shooters consider when buying cartridges for their bolt-action rifles. Well, a shorter barrel bears more accuracy and easier to balance and maneuver. 

An AR 15 rifle weighs less than a similarly configured 308 AR. It is also relatively shorter with the same barrel length. Because of its size, the balance is noticeably better than a 308 Winchester.

beach, balance, wallpaper

While in long-range hunting, the 308 would need to have a longer barrel to reach the required muzzle velocity for bullet expansion. And the problem with a 308 bullet is that the sound can be loud if you use it with a short barrel the sound can be loud. With this, the 6.5 Grendel has an advantage in weight and balance compared to the 308.

Curious about twist rate on barrels? Read 1-7 vs 1-8 twist Blackout 300 here.


Let’s talk about their price next. While it’s true that the 308 has the edge over the 6.5 Grendel or even the 6.5 Creedmoor when it comes to ammo availability, our team gives this point to 6.5 Grendel when it comes to price. The 6.5 Grendel ammunition is inexpensive compared to 308 and 6.5 Creedmoor without sacrificing its quality. 

It’s also an advantage to know that the quality of Alexander Arms ammo and firearms is top of the line. Alexander Arms is very stringent when it comes to quality control on components and construction, so they produce very high-quality guns. So, if you are looking for budget-friendly ammo, the 6.5 Grendel is an ideal fit for you.


In this department, the 6.5 Grendel takes an ultimate win over the 308 because it has good recoil, which helps gain accurate shots well. So when a shooter uses the Grendel, his shot placement will get more attention.

And because the Grendel cartridge is relatively lighter, it has substantially less recoil than a 308 bullet, which is a nice point for the Grendel. Recoil affects accuracy and precision, so it is a must to consider recoil when buying ammo.



As mentioned earlier, a 308 requires a longer barrel to gain the required velocity for expansion for longer range hunting. The 6.5 Grendel has a big advantage in modern powders and cartridge design. It is quite efficient from a short barrel, gaining its speed rapidly.

But looking at their muzzle velocity, the team noticed that the Grendel is a little bit slower when shot at a distance of one hundred yards than the 308 or 6.5 Creedmoor. However, the velocity of the Grendel starts catching up at 200 and 300 yards. And at 400 and 500 yards shot, the Grendel surpasses the 308 in speed. This result is going to continue with further distance energy.

Ballistic Terminal

Ballistic terminal is probably one of the most notable differences between the 6.5 Grendel and 308. The size of the two bullets is pretty different and apparent. And because of their size difference, their sectional density differs, too. 

For those who don’t know well, sectional density affects terminal ballistics.  The 6.5 Grendel has a long and thin cartridge. When a cartridge is lighter and smaller, it penetrates your target better. 

bullet exploding

After testing both cartridges for ballistics for the first time, the team found out that the velocity of both bullets is almost the same. But because 6.5 Grendel is more aerodynamic, this is where the Grendel takes another win against the 308 Winchester, which has a lower sectional density.

Recommended article on rifle bullets: 45 – 70 vs 450 Bushmaster – Key Differences & Why It Matters

6.5 Grendel Pros & Cons



308 Cons Pros & Cons



Which Do We Recommend The .308 or 6.5 Grendel?

Between 6.5 Grendel vs 308, our team recommends shooters to get cartridges like the 6.5 Grendel because it beats the 308 when it comes to affordability, weight, balance, ballistic coefficient, shorter barrel length, better wind resistance, and lower recoil. 

In case you may need to get something on the AR platform that is great for taking a medium-sized game like hunting deers, the 6.5 Grendel is one ideal solution. However, if the price isn’t an issue for you, getting a 308 wouldn’t hurt you much because although 6.5 Grendel won in a lot of aspects, 308 is still a good buy. And since the 308 is in full stock now it’s a good choice. 

Are you still looking for alternative ammunition? Read 6.5 Creedmor vs 7mm-08 Remington here.

Our #1 Recommendation


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