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Shoot-Out at the Mids: 6.5 Grendel vs Bushmaster .450

6.5 Grendel Vs Bushmaster .450

Today, we are going to be pitting two intermediate rifle cartridge giants against each other to find out which one is best suited to your needs: the 6.5 Grendel vs the .450 Bushmaster. Both are arguably some of the top-notch cartridges that you could lay your hands upon, made for your hunting rifle. So the deciding factor becomes your personal requirements and preference. Read on to find out what we like most about each!


The 6.5 mm Grendel was originally intended for use in bolt-action rifles. However, over time, the hunting community found that it was a very good choice for semi-automatic rifles as well. In fact, it actually seemed to work much better in standard SAs than in bolt-action rifles. It is also slated to be expanded into Kalashnikov systems as well.

The .450 Bushmaster was modeled with a key concept in mind- the “Thumper round”. The idea was popularized by gun writer Jeff Cooper, who was also a revered World War II and Korean War veteran. As a result of this concept being prioritized during design development, this ammo in semi-automatics delivers unmatched power without compromising on medium to long-range velocity when it comes to larger hunts.  


The 6.5 mm Grendel was earmarked for AR-15s with the goal to surpass the 5.56mm NATO and .223 Remington cartridges. It features a rimless, bottleneck structure and was modeled upon three different cartridges: the .220 Russian, the 7.62×39mm, and the PPCs. Compared to its predecessors, it has a shorter case with a larger diameter so as to accommodate and ample space for longer, streamlined, and more lethal bullets.

Coming to the Bushmaster .450, it was born out of the dissatisfaction with .22 Remington which lacked significant power and velocity retention, thus limiting hunters to smaller game. The .450 Bushmaster is a straight-walled cartridge unlike the Grendel 6.5, which gives it an edge because of official restrictions and laws in some places that restrict bottlenecks for hunting. It features a standard 43.18 mm case with 57.4 mm overall length after being shortened from the original dimensions of 45 mm and 60 mm respectively. It was created primarily for use in M16 and AR15 rifles, but in recent times has also been adapted for bolt action and break-action rifles as well.

Specifications and Performance

Now, for the part that you all have been waiting for. Let us dive straight into the features of the two cartridges. If you’re a seasoned hunter or a gun aficionado, or if you simply have a fascination for numbers, then I’m sure that this bit is bound to be engrossing for you.

The diameter of the 6.5 mm Grendel case head has been retained from that of the parent cases it drew inspiration from, which makes it larger than the 5.56×45mm NATO— the cartridge it sought to supplant. It has a non-standard AR-15 bolt that was developed for the .50 Beowulf cartridge. When compared to traditional M16/AR15 magazines, a Grendel magazine of comparable capacity typically holds less ammunition. Experts and skilled hunters often consider this cartridge to be the perfect sweet spot between the 5.56 mm NATO and the 7.62 mm NATO cartridges because of its comparatively flatter trajectory and higher ballistic coefficient. In simple speak, this translates to greater accuracy and downrange velocity retention— which in turn allows the bullet to fragment and cause greater damage.

The .450 Bushmaster cannot hold a candle up to the 6.5 Grendel in terms of range. The latter can effectively and humanely drop targets at well over 700 yards, but the former is better suited to close range hunting of medium-sized targets up to 300 yards because of its significantly low ballistic coefficient. Still, it has a decent muzzle velocity and a relatively flat trajectory to flaunt. Plus, since there is less propellant behind the bullet by design, there is a lower chance of overshooting and stray bullets injuring people and causing damage.

Ease of Use

The 6.5 mm Grendel boasts of many feathers in its cap. First of all, it is very small, light, and much more precise in comparison to its counterparts like the .308 Winchester. Second, it has very low recoil— especially when used in lighter rifles. Third, it has a relatively flat trajectory and is pretty wind drift resistant. This makes it a great choice for beginners who might not be used to the recoil and thus run the risk of getting injured. Finally, the 6.5 mm Grendel accomplishes all of these without compromising on efficacy and lethality.

Starting off on the .450 Bushmaster, it is slightly heavier than the Grendel and has a tremendous recoil unless using a muzzle brake, making it unsuitable for absolute novices and kickback sensitive hunters. That said, it is pretty spot on within the MOA up to at least 200 yards and packs a brutal knockout punch in short-range hunting.

Price Point

Affordability of proper, standard quality ammunition, especially in the long run, is one of the biggest factors for hunters and the 6.5 Grendel performs exceptionally well on this front, retailing for as low as $20 per box of 20 rounds. Hornady and Underwood <affiliate links> have well-made and cheap options available both online and in most stores.

The Bushmaster .450 on the other hand, burns a slightly bigger hole in the pocket than the 6.5 mm Grendel. It is moderately budgeted in that it is priced at around $35 per box of twenty rounds. A much more economical way out is to reload the cartridges which can cut costs by almost a half without compromising too much on quality and feel. Further, Starline even manufactures empty brass to facilitate the handloading of the bullets. If you do decide to reload the cartridges by yourself though, then take care to learn about the crimping and appropriate case lengths so that you don’t have to end up clearing out jams.


As mentioned before, since the 6.5 mm Grendel works well with semi-automatic rifles, it is a good choice for those looking to hunt deer and hog with precision. But it is better to steer clear of larger animals like elk and grizzlies because one-shot kills are typically harder. That said, there were reports of this cartridge being adapted for use in the armed forces and special force units as well, so go figure!

On the other hand, the Bushmaster .450 was developed with a singular goal in mind. It was meant to be a pioneering modern rifle for medium to large game hunting. This gun is suitable if you’re out to hunt for animals like deer, boar, elk, hog, or even some bears. Further, it is also a very good option for those on the lookout for something for target shooting and even competitions.

Availability and Compatibility

Generally, ammunition for the 6.5 Grendel of good quality is made available by Federal <affiliate link, if available>, Nosler and Hornady <affiliate link, if available> across different lines and prices. They are well-stocked in online stores and can also be bought in bulk. However, they might be a tad hard to find in every sporting goods store since the cartridge is not as popular as some of its other counterparts. The versatile cartridge is compatible with a wide variety of rifles types, as said earlier— from the regular semi-automatics to bore actions and  

The .450 Bushmaster, too, has ammo available in multiple ranges from almost all major brands like Hornady, Federal, Winchester, and Subsonic <affiliate links>. The nifty thing about the .450 Bushmaster cartridge is that in experienced hands, it can accommodate almost the whole range of .45 caliber bullets.

Final Thoughts

Overall, the .450 Bushmaster and 6.5 Grendel stack up pretty well against their other competition. However, pitting them against each other seems a bit like comparing apples and orange, which yields a narrow result that can only be decided by personal preferences. If you are looking to venture into medium to big game hunting without burning a hole in your pocket and haven’t had a ton of experience yet or if you are prone to recoil accidents, the 6.5 Grendel is a pretty solid place to start. On the other side, if target shooting or big game hunting is your thing and you don’t mind shelling out a bit more on quality ammo on your cartridge, then the .450 Bushmaster is a good option for you.

In the end, before settling on any gear, you should carefully weigh out your situation in terms of experience, cost-effectiveness, and purpose. Try out the things that seem to appeal to you on paper and if you’re not satisfied, remember that there are always tons of more options to explore and choose from!