Although the US military continues to place its trust in the performance of the 5.56x45mm cartridge, many shooters have derided the cartridge over the years as a “poodle shooter,” meaning it’s about powerful enough to kill a poodle, not a person. There’s some truth to that, as US forces have often complained about the inability of the 5.56x45 to put down bad guys. Some enemy forces have to be shot dozens of times before they’re put out of the fight.
Over the years successive fixes have been made to the 5.56x45, leading to the adoption of heavier and heavier bullets. But all of those fixes are limited by the maximum 2.260” cartridge length allowed by the M16’s magazines. Given the case length of the 5.56x45, that requires bullets with a relatively short nose, leading to inferior ballistic performance at longer ranges.
With those problems in mind, numerous designers have gone back to the drawing board to envision new cartridges that would fit in the M16/AR-15 platform but offer significantly greater performance. One of those cartridges that has caught on and gained great popularity among civilian shooters is the 6.5 Grendel cartridge.
Developed through work at Alexander Arms and the Finnish Lapua ammunition company, the 6.5 Grendel is based on the 7.62x39mm cartridge. The 7.62x39 is necked down to 6.5mm and the shoulders are blown out to improve case capacity. The result is a cartridge that is able to fire long, aerodynamic 6.5mm bullets at modest velocities, offering more energy and superior long range performance to 5.56x45, and in some cases even offering superior performance to the 7.62x51mm NATO cartridge.
Due to being based on the fatter 7.62x39 case, pressures in the 6.5 Grendel are kept to a maximum of 52,000 psi. Magazines for the 6.5 Grendel in the AR-15/M16 platform are specific to the Grendel, and hold a maximum of 25 rounds. The 6.5 Grendel is also able to be chambered in the AK platform, although no commercially produced magazines for the cartridge are widely available yet.
Although the 6.5 Grendel hasn’t received too much attention from most militaries, there is some speculation that Yugoslavia might decide to adopt the cartridge as its standard service cartridge. Zastava Arms has chambered its Modular Automatic Assault Rifle in 6.5 Grendel. Steel-cased ammunition is being produced for 6.5 Grendel, and is available on the US market at about 25 cents per round.
The 6.5 Grendel is capable of firing bullets weighing from 90 to 144 grains. The lighter bullets exit the muzzle at higher velocity, while the heavier bullets retain better energy at longer ranges and offer better performance against barriers such as auto glass.
Comparing the ballistics of 6.5 Grendel to 5.56x45 shows how superior the 6.5 Grendel cartridge is.
A 62-grain 5.56x45 bullet exiting the muzzle of a 20” barrel at 3,100 feet per second makes 1,323 foot-pounds of energy. By 300 yards the bullet’s velocity has dropped to 2,125 fps, while energy has dropped to 621 ft-lbs. By 500 yards the bullets has dropped to 1,594 fps, and energy has fallen to 350 ft-lbs, around the same energy as a 9mm bullet at the muzzle.
A 123-grain 6.5 Grendel bullet exiting the muzzle at 2,450 fps from a 16” barrel offers 1,639 ft-lbs of muzzle energy, or nearly 25% greater than 5.56x45. By 300 yards the Grendel bullet is still traveling at 1,972 fps, making 1,062 ft-lbs of energy, or 70% more than the 5.56x45. At 500 yards the Grendel bullet is traveling at 1,689 fps and offers 779 ft-lbs of energy, 123% greater than the 5.56x45. Performance with the 144-grain bullet with a 2,300 fps initial velocity is even better, with 8% more energy than the 123-grain bullet at 300 yards and 12% greater energy at 500 yards.
This increased performance has made the 6.5 Grendel a popular cartridge for both target shooting and hunting. Offering significantly more energy than the 5.56x45 and better ballistics than both 5.56x45 and 7.62x39, the Grendel is rapidly becoming one of the most popular cartridges in the country. While it won’t rival the 5.56x45 anytime soon, and won’t be the type of ammunition you’ll readily come across in a survival situation, it nonetheless can be an important and valuable cartridge in any survival arsenal.