Three New SAAMI Cartridge Standards: 6.5-300 Wby Mag, 6.5 PRC and 300 PRC

Hrachya H
by Hrachya H
Three New SAAMI Cartridge Standards 6.5-300 Wby Mag, 6.5 PRC and .300 PRC (123)

Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) has published three new cartridge and chamber drawings for the 6.5-300 Weatherby Magnum, 6.5mm Precision Rifle Cartridge and .300 Precision Rifle Cartridge. Let’s take a brief look at each of these SAAMI certified cartridges.

6.5-300 Weatherby Magnum

Three New SAAMI Cartridge Standards 6.5-300 Wby Mag, 6.5 PRC and .300 PRC (1)

Introduced in 2016, this cartridge is claimed by the manufacturer to be the fastest production 6.5mm cartridge available. According to the ballistic data on the Weatherby’s website, this monster is capable of accelerating the 127 grain LRX projectiles (BC=0.468) to a muzzle velocity of 3,531 fps. One of the heaviest bullets currently loaded by Weatherby is the 140 grain A-Frame that has an advertised muzzle velocity of 3,395 fps. To download the SAAMI drawing of this cartridge, click here.

6.5 Precision Rifle Cartridge

Three New SAAMI Cartridge Standards 6.5-300 Wby Mag, 6.5 PRC and .300 PRC (2)

This short action cartridge has a rim diameter identical to the belted magnum cartridges that are based on the .375 H&H case. Hornady introduced the 6.5 PRC about a year ago. Currently, the company offers two loads for this cartridge with 143 grain ELD-X® Precision Hunter® and 147 grain ELD® Match bullets traveling at 2,960 fps and 2,910 fps respectively. Here is how Hornady describes the 6.5 PRC:

The name says it all! The 6.5 Precision Rifle Cartridge was designed to achieve the highest levels of accuracy, flat trajectory and extended range performance in a sensibly designed compact package.

Utilizing moderate powder charges that result in repeatable accuracy, low recoil and reasonable barrel life, the 6.5 PRC produces high velocities with performance well beyond 1000 yards.

Rifle makers currently chambering the 6.5 PRC include: Christensen Arms, Fierce Firearms, GA Precision, Gunwerks, Hill Country Rifles, Horizon Firearms, McRee Precision, Montana Rifles, PROOF Research, Savage Firearms, Sauer, Stuteville Precision, Seekins Precision and Trident Armory. Check back often as additional gun manufacturers confirm chambering the 6.5 PRC.

The SAAMI drawing of the 6.5 PRC cartridge can be downloaded by clicking here.

.300 Precision Rifle Cartridge

Three New SAAMI Cartridge Standards 6.5-300 Wby Mag, 6.5 PRC and .300 PRC (3)

To my knowledge, this cartridge hasn’t been officially released yet. Presumably, it is also a Hornady cartridge. It has the same belted magnum size case head diameter as the 6.5 PRC but the maximum overall length is 3.7″ which basically makes it a magnum length cartridge. The 300 PRC cartridge has a 3.64 caliber (1.12″) space over the case which will allow to load it with bullets that have relatively long ogive for the caliber. The maximum average pressure of this cartridge is 65,000 psi. The SAAMI drawing states 2,800 fps muzzle velocity for a 225 grain projectile. You can download the cartridge and chamber drawing of this cartridge by clicking here.

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Hrachya H
Hrachya H

Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at

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  • Abel_Archer83 Abel_Archer83 on Aug 04, 2018

    That 6.5-300 will be a barrel smoker. Wonder how it does ballistically. There are some interesting new cartridges coming along. The 7mm-300WM seems interesting but probably kills barrels as well.

  • MrSottobanco MrSottobanco on Aug 04, 2018

    I think Tim the toolman's favorite rifle is the Weatherby. They put a turbo on everything.