For over 60 years, Remington’s 7mm Magnum has been the most popular 7mm magnum, outpacing the 7mm Weatherby Magnum, 7mm STW, 7mm Mashburn, 7mm WSM and 7mm Remington Ultra Mag. Now there’s a new contender for the middleweight champion, the 7mm PRC. So far, it appears to be amazingly popular for a cartridge that was just introduced a few months ago. Will it unseat the 7mm Remington Magnum as the most popular?
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7mm Remington Magnum
Introduced over 60 years ago (1962), Remington’s “Big 7” was preceded by the 7mm Weatherby Magnum (1940) and various 7mm belted wildcats. The 7mm Weatherby never really caught on, possibly due to the fact it was only available in expensive Mark V Weatherbys, but inspired others to start experimenting. The 7mm Rem Mag quickly became very popular, particularly for Western big game. It’s also worth noting the Secret Service once used the cartridge in counter-sniper weapons because of its excellent accuracy potential and long range performance.
My hunting history with this cartridge goes back over 20 years. I’ve used it for elk, mule deer, pronghorn and the occasional coyote. I’ve also watched a hunting partner drop an Alaskan grizzly with a single well-placed shot with his 7mm Remington Magnum.
The 7mm Remington Magnum and the 30-06 are about the most powerful cartridges most hunters can shoot well from a typical sporter-weight rifle. In my experience, I have to work harder to produce good accuracy from more powerful rifles such as the various 300 magnum rifles, 338’s and 375’s.
The following Hornady ballistics table is for Hornady’s 162 grain ELD-X Precision Hunter ammunition. This long range hunting ammunition for the 7mm Remington Magnum features the highest weight bullet Hornady offers in factory ammunition for this cartridge.
Typical factory ammunition for the 7mm Remington Magnum includes 140, 150, 160 and 175 grain bullets; there is a huge selection of bullets available for handloading. Factory rifles chambered for the 7mm Rem Mag typically feature a 1:9 to 1:10 twist, which works well with conventional bullets in those weights.
Like other magnum cartridges introduced around the same time, the 7mm Remington Magnum is a belted magnum. The belt is unnecessary, but is a holdover from the old 300 and 375 H&H magnums which had such gently tapered shoulders that they needed the belt for headspacing.
Interestingly, the slightly more powerful 7mm Weatherby Magnum preceded the 7mm Remington Magnum by nearly 20 years. That cartridge never became very popular, but the 7mm Remington Magnum has been incredibly successful.
Here at Ultimate Reloader we’ve used the 7mm Remington Magnum to test the then new Enduron powder IMR 8133 as well as 150 grain Hornady ELD-X and CX bullets. We noted excellent accuracy, high velocity, and good results in clear ballistics gel blocks.
The 7mm PRC
Hornady asked us to keep the 7mm PRC under wraps for several months before it was officially released last year. During this time, Gavin built two terrific rifles for the 7mm PRC: a Bergara Premier build and a Freedom rifle build. He also covered 7mm PRC reloading and compared it to 300 PRC and 6.5 PRC.
The 7mm PRC is a modern case design with nearly identical case capacity to the older 7mm Remington Magnum. It’s a sharp-shouldered beltless design.
Hornady specifies a 1:8 twist rate for the new cartridge. This is capable of stabilizing new, longer 7mm bullets such as their own extremely accurate 180 grain ELD-M. The 175 grain ELD-X is also a very long bullet with an exceptionally high ballistic coefficient for a 7mm hunting bullet.
This chart is for Hornady’s 175 grain ELD-X Precision Hunter ammunition.
Note that the 175 grain ELD-X is so long it is unlikely to stabilize in the slower twist rates typically found in 7mm Remington Magnum rifles. This is a key point about the 7mm PRC. This cartridge was designed to utilize very long, high BC bullets with a fast 1:8 twist barrel to stabilize them.
175 Grain Hunting Bullet Comparison
The photo shows the differences between three different 175 grain 7mm hunting bullets from Hornady, Sierra and Nosler. The Hornady is so long that a fast-twist barrel is required to stabilize it.
Until the Hornady ELD-X, I thought the Sierra GameKing 175 grain was the ultimate hunting bullet. The ELD-X is significantly longer than my old Sierra and Nosler favorites, leading to a higher BC. This is a great illustration of the evolution of long range hunting bullets.
Hornady also makes 7mm PRC 180 grain ELD-M match ammunition which Gavin has used with excellent results from both rifles he built.
I started handloading for the 7mm Remington Magnum more than 20 years ago in preparation for a bull elk hunt. While loading for and practicing with the 7mm Rem Mag, I grew to respect the cartridge for its easy shooting qualities, good accuracy and flat trajectory. When the big bull elk fell to a single 175 grain Nosler Partition, I knew it was a dandy hunting cartridge as well.
In fact, I liked the cartridge so much that I bought my son a Bergara Wilderness Ridge chambered in 7mm Rem Mag.
Handloading for the 7mm Remington Magnum is similar to handloading any belted magnum. Though the cartridge was designed to headspace on the belt, adjusting the sizing die to headspace on the shoulder results in longer case life and potentially better accuracy. The cartridge thrives on slow-burning powders such as Reloader 22 and Retumbo. I prefer to load it with 150 – 175 grain bullets. My 7mm Rem Mag rifles have all had 24” or 26” barrels— ideal for generating high muzzle velocity. Typically I’ve been able to achieve the following muzzle velocities.
- 140 gr. bullet = 3200+ fps
- 150 gr. bullet = 3150+ fps
- 160 gr. bullet= 3000+ fps
- 175 gr. bullet = 2850+ fps
When I started looking at the available data for the new 7mm PRC, it seemed prudent to try slower burning powders in it as well. Gavin built one of his 7mm PRC’s with a 22” Bartlein 5R 1:8 barrel. He kept it short with the thought of adding a suppressor.
Built on a Bergara Premier action, it has a Trigger Tech Diamond two-stage trigger, Boyd’s Agility laminate stock, and a Riton X7 Conquer, 3-24 x 50 optic. Accuracy from Gavin’s Bergara 7mm PRC build has been superb! The very effective SRS Ti Pro 3 ST muzzle brake really tames the recoil and makes this magnum rifle easy to shoot well.
Using the 175 grain Hornady ELD-X and 68.5 grains of Retumbo, I saw a 2907 fps average from the 22” Bartlein barrel from my CED chronograph. This is a load I’d absolutely hunt with. It’s a bit more powerful than the 175 grain load I used to drop the 6×6 bull elk with my 7mm Remington Magnum.
I also loaded the 175 grain Hornady ELD-X over Ramshot LRT in Hornady brass with a Federal 215 primer. I hadn’t used Ramshot LRT before, but found the ball powder metered nicely. There isn’t much data out now as the cartridge is still so new, but I started at 77 grains and worked my way up to 80.5 grains. With help from the Caldwell G2, I measured a 2929 average feet per second muzzle velocity.
Hodgdon has been busy testing the 7mm PRC and has more data available now than they did just a few short months ago. The following is from their online Reloading Data Center, and I’m sure it will be included in their 2023 Annual Manual as well.
With a 24” or 26” barrel, 3,000 fps is achievable. That high muzzle velocity combined with a high BC 175 grain bullet should lead to impressive long range performance.
In comparison, here’s Hodgdon’s current data for the 7mm Remington Magnum with a 175 grain bullet:
The 7mm PRC is able to achieve higher muzzle velocity with the same weight bullet because it’s loaded to a higher pressure.
Another interesting note is how little bullet intrusion the 7mm PRC has compared to the 7mm Rem Mag. Long hunting bullets are notorious for taking up significant room below the neck inside the case in 7mm Rem Mag. It isn’t as simple as just not seating 7mm bullets as deeply — the 7mm Rem Mag long action limits OAL.
The 7mm PRC has an advantage here over the 7mm Rem Mag. You can seat the bullets longer and get the brass out of the “donut” area (shape of brass build-up inside case).
Can the 7mm PRC unseat the 7mm Remington Magnum as the most popular 7mm magnum hunting cartridge? Only time will tell. The 7mm PRC has many positives and with the increasing interest in long-range precision shooting it seems like the right cartridge at the right time. Even so, the 7mm Remington Magnum has sixty years of hunting heritage to bolster its reputation as an excellent choice for big game.
It’s not surprising that the two cartridges have similar ballistics, but the edge goes to the 7mm PRC with that long, heavy, high BC bullet. The 7mm PRC also operates at higher pressure than factory 7mm Remington Magnum ammunition, thus producing higher muzzle velocity.
If I was starting out all over again, I’d give the 7mm PRC some serious consideration. It has all the benefits of a powerful 7mm hunting cartridge, but in a more modern package better suited for long range use. Besides, who needs a belt anyway?
Get the Gear
The 7mm PRC is still very new. Components and ammunition are still difficult to obtain, but availability is improving.
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