Reloading Fundamentals for the Fantastic 7mm Remington Magnum

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The year was 1962, and I faced a serious conundrum. No, it wasn’t a matter of life or death, it was much more important than that. I was a college sophomore, and I had finally saved up enough money to buy a big-game rifle. Since it would be my only big-game rifle, it had to do everything, and, well, it had to be perfect. The choices of caliber in those days were considerably slimmer than today, so it was basically either a .270 Winchester or a .30-06 Springfield. I pored over every ballistic chart I could find, but I just couldn’t decide—the heavier bullets of the ’06 or the string-flat trajectory of the .270.

As I pondered, I had a frisson of the first order. I discovered that in 1957, Remington had introduced a round called the .280 Remington. It was right between the bullet diameters of the .270 Win. (0.277 inch) and the .30-06 (0.308 inch). It was, in fact, a 7mm with a bullet diameter of 0.284 inch. The .280 Rem. looked perfect, but, of course, no nearby store had any. Dejected, I sulked.

It was, however, ultimately Remington to the rescue. In this fate-strewn year of 1962, Big Green introduced another 7mm cartridge, one with even more power than my other three contenders and a flat trajectory, and it was housed in the new, spiffy Model 700. I scurried down to the B&J Army surplus store, run by Mr. Bert Franchione, who was always nice to college kids like me. (He figured that we might come back with money someday.) “Please get me one of these Model 700s in this new caliber,” I implored. “Okay, kid,” Bert said.

Weeks went by, no Model 700 appeared. Finally, I was so dejected that I told Bert to cancel the order. But upon a later visit, Bert quickly announced, “It’s here!” I finally gazed upon the object of my dreams and quickly said, “I’ll take it.” The cost of my new treasure was $120. (Remember, that was 1962. Gas was about 20 cents a gallon.)

Remington offered two loads for the new cartridge, a 150-grain PSP and a 175-grain RN. Even then I was a handloader, and since the Model 700 was to be my one and only big-game rifle, I ordered a box each of Hornady 154-grain RNs and 175-grain Spirepoints and some 4831, the military-surplus powder sold by Hodgdon back in those days. I picked data from a loading manual, loaded up those bullets, and was set for everything.

Eventually, I acquired the essentials, not necessarily in this order: loading manual, press, dies and shellholder, powder scale, powder measure, measuring tools (calipers, micrometer, etc.), and components. My press and dies were from C-H, as they were inexpensive and available. I primed cases with the arm that came on the press (a far cry from today’s hand-priming tools). My scale was a simple balance type. As for powder, I started with the aforementioned Hodgdon surplus 4831. And it all worked.

I learned a lot about reloading with that 7mm Rem. Mag. I quickly learned what an “incipient case head separation” was, and to correct for this, I bought a Wilson Adjustable Case Gauge. With it, I re-set my sizing die to just set the case shoulder back about 0.002 or 0.003 inch, so cases headspaced on the shoulder, not the belt. I knew nothing about varying bulletseating depths and just used what was listed in the loading manuals. That seemed to work out okay, as I managed to not blow up myself, and my loads were acceptability accurate.

I shot my first deer with the 7mm Rem. Mag. in 1967, and over the next 40 years, the 7mm Rem. Mag. added to my list of firsts—bighorn sheep, pronghorn antelope, mule deer, elk, and a few coyotes and many black-tailed jackrabbits.

Controlling Some Variables

Handloading is a lot different these days. There are dozens of hand tools and sophisticated measuring gadgets, and the many bullets and powders available are astonishing. The number of potential load combinations is huge, but this is not a detriment. It’s a boon, as it allows the reloader to pick and choose components and fine-tune his ammo for the hunt at hand.

Additional big-game rifles came and went, as I broke my “one rifle for everything” rule. I am a big fan of the Ruger No. 1 single-shot rifle, and in 2018, I stumbled upon a like-new No. 1-B in 7mm Rem. Mag. With it, I have taken exactly zero game, but I have had great fun combining as many of the new super bullets and high-tech powders as I can and testing those loads in the rifle’s 26-inch barrel with an eye toward equaling factory load velocities and accuracy. Let’s take a look at some of the results.

One of the controllable variables was case weight. There was a slight variation in the weight of empty cases. The average weights of three brands of 7mm Rem. Mag. cases in grains were 229.9 for Winchester, 232.6 for Remington, and 239.1 for Federal. Conclusion: It’s a good idea to segregate cases by brand.

The choice of primers can be daunting—or simplified. For my early loads I used Winchester standard Large Rifle primers for extruded powders and Federal 215 Large Rifle Magnum primers for spherical powders. Nowadays, I tend to stick with Magnum primers for most loads in this caliber, using either the Federal 215s or CCI 250s. In my opinion, these two primers are interchangeable.

When it comes to suitable powders for the 7mm Rem. Mag., these days reloaders never had it so good. Shortly after the round was introduced in 1962, Speer issued a two-page pamphlet with laboratory-tested loads for the firm’s 130-, 145-, and 160-grain 7mm bullets. Data for eight powders were shown: 5010, H570, H450, 4831, 4350, 4320, 4895, and 4064. Presumably, except for the first three listed, the others were from the “IMR” series. These data were repeated exactly in Speer’s No. 6 manual (1964). Note that 5010, H570, and H450 have long been discontinued. Not surprisingly, 4831 delivered the highest velocities with all three bullet weights.

Speer’s tenth manual (1979) listed what we might class as “slow burners” like Norma MRP, IMR 4831, and IMR 4350. They were the mainstays. A few other much faster powders that today would be considered unsuitable were IMR 4320, IMR 4064, and IMR 4895. (A reduced load with IMR 4198 was also presented.) The initial 7mm Rem. Mag. factory ammo was loaded with a non-canister powder called IMR 7828 that was not then available to the public. But by 1987, load data for IMR 7828 appeared in Speer’s eleventh manual, but only for 160- and 175-grain bullets. But IMR 4831 and MRP still produced the highest velocities with those bullets.

Fast forward to today. Handloading the 7mm Rem. Mag. is extremely popular. In fact, the cartridge is number seven on RCBS’s list of rifle die sales. Dies, presses, and tools of all sorts are offered to the reloader. In addition, components have proliferated, too. In the past few years, what we can call the “really slow burners” have appeared, and many are super for the great 7mm Rem. Mag. In addition, some have ingredients that retard and/or eliminate copper fouling, the bane of the accurate rifle.

The 1996 Nosler reloading manual (Number 4) offered a prescient tip for reloading the 7mm Rem. Mag.: “Any powder having a burn rate equal to or slower than IMR 4350 will likely yield good results with all bullet weights.” Nosler also recommended Federal 215 Magnum primers for “more uniform ignition.” Hodgdon and IMR have several relatively new propellants that are great for the round. In addition to standbys IMR 4350 and IMR 4831, other winners include Hybrid 100V, Superformance, H1000, and Retumbo. And really new is Winchester StaBALL HD. The StaBALL family (which also includes StaBALL 6.5 and StaBALL Match) is unique in that these are the first Ball powders to incorporate uniform metering and chemical ingredients to retard copper fouling and temperature insensitivity in the same propellant.

A Few Loading Tips

The tenets of careful reloading apply to the 7mm Rem. Mag. just like other cartridges and are known to most astute reloaders. Case cleaning, preparation, and trimming are the place to start. As noted, careful case sizing so that the cartridge headspaces on the shoulder, not the belt, is important. In addition to the Wilson gauge mentioned earlier, Hornady, RCBS, and other firms offer gauges to quantify this important detail. Many important technological advances have been a boon to reloaders of this round. Two powder families offer advanced propellants for the 7mm Rem. Mag. Alliant has a slew of powders in the Reloder Series that find use in this cartridge. Many hundreds of loads are shown in various manuals for the many fine established propellants.

• Priming is best done with one of the many hand tools available. It is easier and keeps greasy fingers off the sensitive primers.
• Powder dispensing is either with a drum measure or weighing each charge. Reloaders of the 7mm Rem. Mag. are unlikely to load large quantities of ammo, so weighing each charge is not much of a problem.
• The huge variety of 7mm bullets available is truly mind-boggling. After determining the purpose of the load, a suitable bullet surely can be found. In these days of shortages, of course, it doesn’t hurt to have two or three candidates picked out for testing, just in case.
• Load data for bullet weights from 120 to 180 grains are available, but bullets weighing 130 to 150 grains are most appropriate for deer and similarly sized game. Good all-around weights are 150 and 160 grains. Standouts include the Speer 160-grain Grand Slam and the 150-grain ELD-X and 154-grain SST and InterBond from Hornady.
• The hunter can never go wrong with the Nosler Partitions, which are available in 7mm in weights that handle game from antelope and deer to elk and moose: 140, 150, 160, and 175 grains are offered. Plus, the 120-, 140-, and 150-grain Ballistic Tip Hunting and 120-, 140-, and 160-grain AccuBonds are reliable performers, too. Not to be overlooked are the 155-grain Edge and 140- and 160-grain Trophy Bonded Tip bullets from Federal.
• In case you need a non-lead bullet, I’ve had good success with those types from Hornady, Barnes, and Nosler in weights ranging from 139 to 150 grains.
• However, keep in mind that just because you have data for a 180-grain bullet, many heavy (i.e., long) bullets will not stabilize in the 1:9- or 1:9.5-inch twist of many 7mm Rem. Mag. rifles. This is no hindrance, as plenty of 160- and 175-grain bullets are made for bigger big game.
• Bulletseating depth has taken a step forward since I started reloading. Tools to determine the length of a cartridge with a specific bullet seated to touch the lands are available, and they allow the reloader to seat the bullet to whatever depth wanted for each different bullet. Experimentation with seating depths can produce outstanding results because seating depth can dramatically affect accuracy.
• I had three rifles for the development of the load data presented here. In the Mossberg Patriot, I tested six loads with IMR 7977 powder, with excellent results. The group average of these loads was 1.16 inches, with the top prize going to the Sierra 160-grain Tipped MatchKing HPBT at 0.75 inch over 69.0 grains at 2,770 fps.

In the Ruger No. 1-B, the overall group average was 0.99 inch, and the smallest group was with the Federal 140-grain TBT with 63.2 grains of IMR 4831 at 3,019 fps. Close behind was the Hornady 139-grain GMX over 73.3 grains of StaBALL HD at a velocity was 2,989 fps.

Note: Original Model 700s had 1:9.5-inch twists, but after a few years, that was changed to a 1:9-inch twist. The No 1-B also has a 1:9.5-inch twist.

My old 62-year-old Model 700 plugged along with a modest selection of loads, and it proved that it could still bring home the venison. Long ago I determined that IMR 4831 was the best powder for my old Model 700, so I skipped many other fine propellants and brewed up a few representative loads with it and several big-game bullets. I have used all of them on game, except for the Hornady 139-grain GMX. The Speer 130-grain Hot-Cor load is my “coyote” load, and it was very effective on a small Texas axis deer. The Nosler 150-grain Partition was effective on elk, and the Hornady 175-grain Spitzer took down my sheep. If you can’t do it with a 7mm Rem. Mag., you probably didn’t need to do it in the first place.

Okay, one more load. Step back in time with me. Recall that when I got the Model 700, I also bought some Hornady 154-grain RN bullets. Sharp-eyed readers will note this “retro load” listed in the load data chart. This is the load with which I shot my first deer in 1967, a fat whitetail doe. The range was all of 20 yards. I was astounded that I had actually gotten a deer, and I distinctly remember reaching out and touching the deer to see if it was real.

I still have part of the original box of those RN bullets that I used in that load. (This bullet is no longer listed in the Hornady catalog.) I had no chronograph in those days, but for this report I duplicated the load as closely as I could with Winchester cases and WLR primers (which were called No. 120 in those days). The surplus 4831 propellant I used then hasn’t been available for decades, so I used a charge of 60.0 grains of the current H4831 that approximated my deer load. The velocity was 2,555 fps, and it grouped into 1.61 inches. Not terrific, but this rifle has a round count of 1,398. I have an inkling that the old Model 700 and this load may accompany me on this fall’s deer hunt, just for old times’ sake.

I did not list the velocities of the two original Remington factory loads, also purchased in 1962, in the chart. However, their velocities in my Model 700 were 3,082 fps for the 150-grain PSP and 2,962 for the 175-grain RN, and both grouped into about 1.5 inches.

In the 62 years that have elapsed since I got my first 7mm Rem. Mag. rifle, many other rifles and cartridges have been carried up and down mountains and across seemingly endless prairies, and I enjoyed them all. Many fine examples of nature’s bounty have been brought home to the walls and freezers. But nothing replaces the many unique hunting adventures I’ve had with the Model 700 in 7mm Rem. Mag. It is arguably America’s most popular magnum cartridge.

As Terry Wieland reminded us in his superlative book titled Great Hunting Rifles, when an old-time London gunmaker delivered a finished rifle to a customer, it was said that it was “sent home” to join the family, recognized as having a life of its own. Thus, like a revered family member, a 7mm Rem. Mag. rifle continues to contribute. The hunter is never poorly armed with a 7mm Rem. Mag. rifle stoked with carefully prepared handloads that are powerful, accurate, and dependable. Long live “Remington’s Big 7.”

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