Hornady 6.5 PRC - A 'Magnumized' 6.5 Creedmoor
August 01, 2018
Hornady's 6.5 Precision Rifle Cartridge (PRC) is a "magnumized" 6.5 Creedmoor. It offers about 250 feet per second (fps) more velocity than the 6.5 Creedmoor for any bullet weight chosen. For comparison, consider the move from a .308 Win. to a .300 Win. Mag. will net about a 300 fps increase, so the "magnum" title is a good fit for the 6.5 PRC.
The 6.5 PRC is the king of all the "magnum" 6.5 cartridges because it offers fantastic performance without excessively shortening barrel life or giving punishing recoil. A 6.5 PRC has enough barrel life for you to shoot a competitive season without having to replace your barrel. Given that it fits in available detachable box magazines, is also a huge benefit.
While I favor the 6.5 PRC for Precision Rifle Series (PRS) matches out west or in high-wind environments, it was originally developed as a long-range hunting round. Hornady opted to design a short magnum hunting cartridge around the 6.5mm caliber because the rifle-shooting population was finally embracing this caliber and its superior ballistic coefficients it offers.
Math plays a significant role in long-range shooting and the math behind the 6.5mm is compelling. It offers high muzzle velocity and the heavy-for-caliber bullets hold on to that velocity well.
Birth of a Cartridge
Hornady started the design process for the 6.5 PRC with the idea that 60 grains of powder behind a heavy 6.5mm bullet was an ideal combination. Any more powder than that, a cartridge is significantly overbore.
"Overbore" is a term that gets thrown around a lot when discussing magnum cartridges and all it means is that a portion of the unburned powder column travels past the chamber's throat and into the bore. This is like scouring the throat with an abrasive every time the rifle fires. Once the throat erodes, the barrel is "shot out" and requires replacement. So, Hornady settled on 60 grains of powder as the limit to ensure the cartridge provided decent barrel life.
Hornady worked with George Gardner on the predecessor to the 6.5 PRC, the 6.5 Short Action Ultra Magnum (SAUM). Gardner is the owner of GA Precision and he made the first successful effort to create a short magnum 6.5 cartridge. Both Gardner and Hornady knew that the best parent case for a 6.5 short magnum was the .300 Ruger Compact Magnum (RCM). However, when Gardner was working on developing the 6.5 SAUM, there was no .300 RCM brass to be found. Since this would be a wildcat cartridge, he used the .300 SAUM case as his starting point and the 6.5 SAUM was born.
When it came time to make a factory 6.5 short magnum, the idea of getting SAAMI certification for the 6.5 SAUM didn't last long. The 6.5 SAUM saw a couple of different chamber specifications during its life, so picking the most recent iteration meant leaving the early adopters with compatibility issues. Hornady also didn't like a couple of the SAUM case dimensions, so they started where everyone wanted to in the beginning: the .300 RCM.
Unlike the SAUM, the RCM has no rebated rim. The case head is sized at .532-inch as is the case body just forward of the case head. The case has a slight taper until it hits the 30-degree shoulder. Hornady determined case length by starting with a 140-grain bullet and seating it to a depth that kept the bullet's bearing surface above the neck/shoulder junction, with an overall length no greater than 2.96 inches. Keeping the bullet out of the case not only ensures efficient use of case capacity but prevents the powder column from bending the bullet or pushing the bullet into a yaw before it engages the rifling.
Lighting the Fire
The rifle I used to test the 6.5 PRC factory loads was a custom-built affair from Mile High Shooting Accessories with a 26-inch barrel. The 143-grain Extremely Low Drag — eXpanding (ELD-X) bullet had a muzzle velocity of 3013 fps and the 147-grain ELD-Match (ELD-M) had a muzzle velocity of 2989 fps. Both loads stay supersonic up to 1 mile under a standard atmosphere. That's an awful long reach for a light-recoiling rifle.
The test rifle also had a muzzlebrake and concerns about excessive exit pressure and corresponding muzzle blast were not warranted. Magnum rifles with their huge case capacity can be awfully loud whether or not the rifle wears a muzzlebrake. All that powder turns into a truckload of hot gas that makes a ton of noise when it exits the muzzle.
The 6.5 PRC was very unlike a magnum from the muzzle blast perspective, and for that I'm thankful. Long-range sessions are so much more enjoyable when it doesn't sound like a cannon firing every time you pull the trigger. Whether it's hitting steel a long ways away or hunting with one of the flattest-shooting cartridges available, the 6.5 PRC is a rifleman's dream.
|Load||Velocity (fps)||ES||SD||Best Group (in.)||Average Group (in.) |
|Hornady 147-gr. ELD-M ||2989 ||66 ||28 ||.34 ||.45 |
|Hornady 143-gr. ELD-X ||2013 ||42 ||21 ||.54 ||.61 |
Note: Accuracy is the average of five, five-shot groups at 100 yards. Velocity is the average of five shots across a LabRadar chronograph adjacent to the muzzle.