Speedy 7mms have multiplied since 1943. Here, with the champs and the flops, is the latest.
by Wayne van Zwoll
It stayed only a few days. Not that I don’t like 7mms. I just couldn’t justify buying another now. The Savage 110 Ultralight wore the company’s adjustable Accustock under a 22-inch Proof carbon-fiber barrel rifled 1 turn in 8 inches. Such steep spin stabilizes the long bullets with heady ballistic coefficients that help the 7mm PRC (Precision Rifle Cartridge) hit targets far away.
Attaching a 4.5-14x Burris, I hied off to the range with a couple boxes of Hornady loads. The 6-pound rifle was nimble in hand, and reasonably civil in recoil. Savage had claimed a “significant recoil reduction” over the 7mm Remington Magnum. Well, maybe. Hornady’s 175-grain ELD-X bullets sent at 3,000 fps bring over a ton of energy past 500 yards! You don’t get that without a tap on the clavicle. The rifle cycled without fault. Groups of just under an inch had bullet holes that kissed.
At $1,709, the Ultralight is mid-priced, and a finalist for hunts in steep country likely to produce long shots. Savage also chambers the 7mm PRC in its straight-pull Impulse. Industry-wide, rifles in 7mm PRC are multiplying. They range from full-dress “long-range” models to affordable entry-level bolt guns like Ruger’s American and Mossberg’s Predator.
The 7mm PRC splits the difference, physically and ballistically, between the 6.5 and .300 PRC. Like them, it was developed by Hornady on the .375 Ruger case, whose .532 rim fits common “magnum” bolt faces. Shoulders on all three PRCs are set well back. In this they mimic the 6.5 Creedmoor, based on the .30 T/C. Heavy pointed bullets can be used without exceeding practical cartridge length or placing the rear of the ogive (tapered section between a bullet’s shank and tip) below the case mouth.
While its 2.28-inch hull suggests a short rifle action, the 7mm PRC’s loaded length of 3.09 makes it a better fit for actions that handle the .30-06, whose loaded length is 3.34 inches. Short belted magnums developed in the 1950s and ’60s were so proportioned, as are more recent hotrods like the .28 Nosler.
The 7mm Remington Magnum’s belt is one difference between that cartridge and the 7mm PRC. A century-old feature, the belt is a headspacing device. Like the rim of the .30-30 and other early rounds for single-shot and lever-action rifles, it’s the “stop” that arrests the cartridge as it enters the chamber. The 7mm PRC headspaces on the shoulder, per the .30-06 and a host of other modern rimless cartridges.
Purists will tell you headspacing is best done at the shoulder, that firing stretches belted cases just ahead of the web (thick section of the head inside the belt). Result: shorter case life. That’s true, but of no concern to shooters who use only factory loads. Handloaders can avoid undue stretch after first firings by neck-sizing only. That is, instead of squeezing cases back to original dimensions in a full-length die, they can set the die a penny’s thickness above the shell-holder. The neck is sized and opened to hold a bullet, but the shoulder is not set back. The cartridge then headspaces on the shoulder in that chamber, as would a case without a belt. Of course, chamber dimensions can differ slightly, one rifle to the next. So, neck-sized cases from a generous chamber won’t necessarily enter a tighter one.
Beyond banging steel plates at four-figure distance, how will the 7mm PRC earn street cred in the crowded field of frothy 7s? Its 160- and 175-grain bullets at 3,000 fps offer a useful combination of bullet weight, sectional density, and speed for deer, elk, moose, and African plains game. But Remington’s 7mm Magnum shares those numbers, as do its 7mm Short Action Ultra Mag (SAUM) and the 7mm Winchester Short Magnum (WSM). Ditto the 7mm Shooting Times Westerner (STW). Add the 7×61 Sharpe & Hart, the 7mm Weatherby Magnum, and the 7mm Blaser Magnum — all loaded by Norma.
Hoo boy! So, what edge can the 7mm PRC claim over these worthy 7s? In a word, reach. At this time, it is the only 7mm commercially loaded with Pinocchio-nosed 180-grain match bullets. These reach 500 yards, clocking over 2,400 fps and packing more than 2,250 ft-lbs.
But they’re not game bullets. Historically, hunters have determined the fortunes of 7mms, albeit the first 7mm loaded for hunters was designed for soldiers.
Germany’s 7×57, or 7mm Mauser, appeared in 1892 at the dawn of the smokeless era. Based on the 8×57 (in truth a 7.9×57), it fired .284-diameter bullets from a case 2.244 inches (57mm) long. Heavy round-nose bullets were standard in 7×57 hunting ammunition long after armies adopted pointed bullets. In 1945, 175-grain loads at a listed 2,460 fps sold under Remington and Peters, Winchester, and Western brands with a 139-grain Remington spitzer at 2,900. You could buy any for $1.93 a box. One of few 19th-century rounds to get a second wind with modern bullets, the 7×57 is now most commonly loaded with pointed 140-grain bullets at 2,660 fps. Its use in classic rifles by sheep hunters has given it lasting appeal. So have the exploits of famed ivory hunter W.D.M. Bell, who aimed his 7×57 expertly to brain elephants with full-jacketed bullets.
My first 7×57 was a Ruger No. 1A. It had knock-out walnut and, with a 3x Leupold, seemed the perfect mountain rifle — though its throat was long as a bad movie. At timberline one morning, a heavy-racked mule deer rocketed from underfoot. The little single-shot leaped to cheek, a 140-grain Speer sped away and the buck somersaulted over the rocks. An exciting climax. It’s what I remember when someone holds forth on killing game a kilometer off with bullets of mind-bending ballistic coefficient.
A year after Spain adopted the 7×57, the Spanish government replaced the 1892 Mauser rifle with the Model of ’93. It would endure as the “Spanish Mauser,” though Mexico and several South American countries embraced it, too. The 8×57 (with pointed .323 bullets replacing blunt .318s) would arm German infantry through two world wars. But 7mm cartridges had a foothold.
In 1907, the 7×57 was blessed with a British name: .275 Rigby. Holland & Holland’s .275 Belted Rimless Magnum Nitro followed in 1912. Two years later, Jeffery announced its .280 Rimless based on the .333 Jeffery. Its 140-grain bullets clocked 2,800 fps. Germans got similar performance from the 7×64 Brenneke in 1917. It preceded by 40 years the almost identical .280 Remington.
Stateside during the 1920s and ’30s, wildcatters dreamed up myriad 7mms. Few got commercial traction. Charles Newton failed to interest gun-makers with his .280. Western Cartridge (which loaded .256 and .30 Newton cartridges until 1938) briefly listed the .276 Dubiel; but the potent .280 Dubiel, with .288 bullets in a reconfigured .300 H&H hull, remained an orphan. Then, in 1944, Roy Weatherby introduced his 7mm Magnum. Stoked to 66,000 psi, it sent 160-grain bullets at a claimed 3,200 fps. In 1953, Norma began loading the 7×61 Sharpe & Hart, whose 2.39-inch hull was .11 shorter than those of .30-06-length magnums to follow. Meanwhile, Field & Stream shooting editor Warren Page tramped game fields world-wide with his 7mm Mashburn Magnum.
By 1962, belted 7mm wildcats abounded. But Wyoming outfitter and firearms buff Les Bowman gets credit for the version Remington adopted. Using Huntington dies, he necked down .338 Winchester Magnum cases and, with ordinary powders suited to the .270, sent 160-grain bullets at 3,150 fps. Recoil was like that of a .30-06. After Remington’s Mike Walker killed an elk with it, Bowman began pitching it in ads. Appearing in the new Model 700 rifle, the 7mm Remington Magnum was an instant hit. Oddly, early factory loads featured only 150- and 175-grain Core-Lokt bullets. Claims of 3,250 fps and 3,000 fps soon gave way to the more realistic 3,110 and 2,860. Remington now loads 160-grain Core-Lokt Ultra Bondeds at 3,000 fps.
The first ADL and BDL Model 700 rifles in 7mm Magnum listed for $114.95 and $139.95. They had stainless barrels rifled one turn in 9 ¼ inches. Because stainless steel resists bluing, they were copper-plated, then tinned and blued. In 1967, Remington turned to chrome-moly for all M700 barrels.
I’ve used the 7mm Remington Magnum for decades. A bull elk, bellowing from a gorge that fed Hell’s Canyon, drew me off the rims. Scrambling down the steeps, I felt the wind pivot and heard hooves clatter on rock. A mad dash through second-growth gave me a peek, prone, to the chasm’s mouth. The elk emerged and paused at 300 yards, just before slipping behind a bluff. Sling taut, I nudged the Redfield’s crosswire high on the shoulder and crushed the trigger. He tumbled to my 160-grain Partition.
That elk could have been shot with a 7mm PRC, had the cartridge been available then. But not all game obliges with a side-to pose out yonder. Historically, bullets fashioned for flat flight and long-range hits have not excelled up close. They’re designed to expand reliably after distance has sapped their speed, so at short range may not drive as deep or retain weight as well as bullets of stouter build, especially on quartering game. Also, a long, pointed nose offers no edge in the woods. For any given bullet length, you get more weight with traditional nose profiles. In cover, I’m sweet on heavy Swift A-Frame, Federal Trophy Bonded, Norma Oryx, and Nosler Partition bullets. You can handload those in any 7mm — or find them in factory loads for the 7mm Remington Magnum.
The success of Remington’s belted 7 inspired other 7mms. Having shot elk with the civil 7mm-08 and .280, I’ve no need to brook the bellow and kick of the jumbo-size 7mm Remington Ultra Mag.
Hunter support for frisky but efficient 7mms is strong. So, prospects for the 7mm PRC beyond its long-range steel-plate duties are bright. Here’s how it compares, ballistically, with other peppy 7s:
and with 175-grain loads….
Notes on Spin
Why did Remington choose 1-in-9 ¼ rifling twist for early M700 rifles in 7mm Magnum, given its factory loads with heavy 175-grain bullets? That pitch (later changed to 1-in-9 ½ and 1-in-10) was and is adequate for hunting bullets popular then. The evolution of longer bullets, with sleek noses and tapered heels, hiked twist rates. The flat-base, round-nose 175-grain bullets of yesteryear flew straight spun from in 1-in-10 rifling because they were shorter than today’s rocket-shaped bullets of the same weight.
High velocity has long seduced shooters. But over distance, fast bullets lose much of their lead to drag. A bullet entering still air at 3,000 fps meets a stronger headwind than does a bullet clocking 2,800. Example: The 7mm Remington Magnum starts a 162-grain ELD-X at 2,975 fps; the 28 Nosler launches it at 3,175. A 200-fps difference. But velocities at 400 yards are 2,406 and 2,578 fps – a 172-fps gap that continues to shrink as range increases. Bullets of high ballistic coefficient excel at distance because they fight drag well, but any bullet driven fast sets up more drag and decelerates at a faster rate than the same bullet traveling at lower speed.