UNDERSTANDING THE PRCs

By

Craig Boddington

Introduced in 2018, the 6.5 PRC got in under the wire before Covid struck. It jumped on the 6.5mm bandwagon, and made significant inroads before the world shut down. Formally introduced at SHOT Show in 2019, its sibling .300 PRC had less fortunate timing.

I try to keep up on new developments, but the .300 PRC was nearly out of diapers before I laid eyes on a cartridge! And it didn’t much matter: Couldn’t get a rifle to play with and, even if I could, no ammo! I first saw the 6.5 PRC in the fall of ’19, but didn’t hunt with it until the following season. I was slower yet to gain experience with the .300 PRC. In the fall of ’21 I hunted with two borrowed .300 PRCs, but just now got my hands on a rifle I can spend quality range time with.

Despite similar names, the 6.5 and .300 PRCs are quite dissimilar cartridges. Both are based on the .375 Ruger case, jointly developed by Hornady and Ruger in 2006. It follows the “model” of shorter, wider, unbelted case design. However, instead of a much fatter case, which causes a bolt face mismatch—and feeding problems in many actions—the .375 Ruger uses the same .532-inch rim and base of standard belted magnums, without a belt. The .375 Ruger quickly spawned the .416 Ruger and, shortened, the .300 and .338 Ruger Compact Magnums (RCMs).

PRC stands for “Precision Rifle Cartridge,” after the Precision Rifle discipline. The 6.5 PRC is actually based on the .300 RCM case necked down to 6.5mm (.264-inch bullet), short enough to fit into a short action. Despite supply challenges, the 6.5 PRC seems to have caught on nicely. This is almost certainly because, at long last, the 6.5 Creedmoor made American shooters aware of the ballistic advantages of the long, aerodynamic 6.5mm (.264-inch) bullet.

The .300 PRC uses the full-length .375 Ruger case (2.580 inches), necked down to take a .308-inch bullet. So far, it has not been as popular as its 6.5mm little brother. This may be pandemic timing, but there are other factors. The shooting world fell in love with the efficient, light-kicking 6.5 Creedmoor, but folks are asking it to do more than it should. It is a wonderful long-range target cartridge. In my view it is not a long-range hunting cartridge, and at best a marginal elk cartridge. About 300 fps faster, the 6.5 PRC shoots flatter and delivers more energy. It has more recoil than the Creedmoor, but remains pleasant to shoot.

The 6.5 PRC’s performance, 140-grain bullet at roundabout 3000 fps, is not new. That’s what the .264 Winchester Magnum has offered since 1958, and the 6.5-284 Norma comes close. All three are credible long-range hunting cartridges and fully adequate for elk. Faster 6.5mm cartridges deliver more, but they are over bore capacity. Powder selection is limited, and barrel life is reduced. I think the 6.5 PRC is in the 6.5mm “sweet spot.”

I love my .264, but let’s face it: The cartridge is nearly obsolete. There are no flies on the 6.5-284. However, despite a cult-like following, the 6.5-284 has been chambered to few factory rifles, the .264 now to almost no new rifles. Actual cartridge performance depends on loads and pressure, but case capacity offers a ballpark gauge. The 6.5 PRC has a case capacity of 68.8 grains. The .264 Win Mag’s case capacity is 84.1 grains, while the 6.5-284 has case capacity of 68.3 grains. Since velocities are much the same, obviously the PRC and 6.5-284 have more efficient case designs.

Wit sleek, modern case, the 6.5 PRC was designed around the increasingly long, high BC “low drag” projectiles. SAAMI specifications call for a fast 1:8 twist, but many shooters building 6.5 PRCs use faster twists. Virtually all .264s, and many early 6.5-284s, are barreled with 1:9 twists. I’m not re-barreling my .264, and I doubt staunch 6.5-284 fans are abandoning their babies, but the 6.5 PRC is coming on fast, chambered to more platforms, with growing ammo sources. Haven’t given up on my .264, but I bought a 6.5 PRC, the excellent (and excellently priced) Springfield 2020 Waypoint.

So far, the .300 PRC has not come on as strong. We Americans love our .30s but, unless we need the capability, we aren’t crazy about .30-caliber recoil!  With or without the word, the .300 PRC is a full-up magnum cartridge, and we already have plenty of fast .30s. It’s a crowded field, the .300 PRC going head-to-head against the world’s most popular magnum, the .300 Win Mag.

With similar case length, the .300 PRC’s wider case has slightly more case capacity than the .300 Win Mag: 77 grains for the PRC; 72.7 for the Win Mag. This suggests it’s capable of more velocity. Also, it was specified for higher pressure: 64,000 psi for the Win Mag; 65,000 for the PRC. Raw powder space is one thing, but how it’s utilized depends on bullet seating depth, and how far out bullets can be seated and still fit in magazine boxes. As with the 6.5 PRC, the .300 PRC was designed to take advantage of long, heavy bullets.

It is a standard-action-length cartridge…sort of. The .300 PRC case was SAAMI-specified for a much great maximum overall length than the Win Mag: 3.7 inches vice 3.34 inches. So, competition shooters going to the .300 PRC are often using full-length (.375 H&H) actions so they can use the longest, heaviest bullets seated out, taking greater advantage of the case capacity. Similarly, some shooters are also putting the 6.5 PRC in a standard (.30-06 action), rather than a short (.308 action).

That’s one beauty of the PRCs: As new cartridges, they are chambered in the most modern platforms. Depending on the bullets you intend to use, the .300 PRC can also call for a faster twist. Most .30-caliber cartridges use a 1:10 twist. With the heavier—and especially longer—bullets currently in vogue, this isn’t fast enough. The .300 PRC is SAAMI-specified for a faster 1:8 twist, able to stabilize the long .30-caliber match bullets up to 250 grains.

Velocity suffers with heavy bullets, but that’s also what the PRCs are about: Getting those long bullets out there where they can do their work. Honestly, if you want to shoot standard 180-grain (to maybe 200-grain) hunting bullets in a fast .30-caliber, the .300 PRC offers no appreciable advantage over established fast .30s. The PRC is faster than some, not as fast as others, but comes into its own with long, heavy, high-BC bullets.

So far, if you want a fast 6.5mm that really struts 6.5mm capability, the 6.5 PRC is the clear winner. The .300 PRC is not such an obvious choice. Better with heavy bullets, for sure, but I doubt it will become as popular as the .300 Win Mag, and it brings the full complement of fast .30-caliber recoil, not needed by everyone.

Oh, did I forget accuracy? If unprecedented accuracy were assured, then all old favorites would be discarded. Reality: Maximum accuracy is not dependent on case design. The modern wider, unbelted cases are conducive to accuracy, but quality of barrel, sound assembly and bedding, and good ammo are more important to accuracy than case design. So far, my experience with the PRCs is limited: Four each in 6.5 and .300. Most have been “high end” rifles from Allterra, Christensen, Gunwerks, and Springfield. Expected them to shoot, and they did. So did a wonderfully inexpensive Bergara in .300 PRC!

Just yesterday, I took a new Gunwerks NXT .300 PRC to the range. Awesome rifle. I suppose I expected a miracle, but you rarely get one on the first try. First two five-shot groups were 1.5 inches. Not exceptional, but a good start from a brand-new barrel, and at the moment I only have one load to try. After break-in, and fiddling with loads, all the PRCs I’ve shot have grouped much better. I’m certain this one will, looking forward to seeing just how well it groups. However, let’s get real: Two of my pet rifles happen to be a Jarrett .300 Win Mag; and a .264 with an exceptional Obermayr barrel. I have yet to see a 6.5 PRC that groups as well as my .264; or a .300 PRC that groups as well as my Jarrett. They’re out there, but exceptionally accurate rifles—in any chambering, old or new—are tough to beat…and cannot automatically be beaten by case design alone.

I’m not rebarreling either of them just to get a modern case—or to shoot heavier bullets. Now, if I were starting from scratch and I wanted a versatile, fast 6.5mm, I’d go with the PRC. And, if I wanted a fast .30, I’d take a hard look at the .300 PRC. Understanding, if will be a long time, if ever, before it’s as available as the .300 Win Mag.