Fast, faster, fastest: Sorting through the .300 magnums

Fast, faster, fastest: Sorting through the .300 magnums

Boddington, Craig

Americans have loved their .30-caliber cartridges ever since the .30-40 Krag came along in 1892. During the transition from blackpowder to smokeless powder cartridges, the .30-30 Win., too, was a red-hot number, but the ballistics of both were soon eclipsed by the .30-’06 Sprg. All three became exceedingly popular, and the .30-’06 remains America’s most popular sporting round. But ever since the teens, wildcatters and firearms manufacturers have sought to increase .30-cal. performance– which has usually meant increasing the velocity through larger cases with greater powder capacity.

In strictest terms, “magnum” (taken from a French word for an extra-large bottle of champagne) connotes a cartridge that is faster and/or more powerful than an existing cartridge using the same bullet diameter. In that context, the .30-40 Krag could be considered a magnum to the .30-30, and the .30-’06 to the .30-40. And if we consider the .30-’06 as a performance baseline-a pretty darned good baseline at that-for .30-cal. performance, then all of our “fast .30s” are true magnums in every sense of the word.

The first American fast .30 was the .30 Newton, circa 1913. One of Charles Newton’s many creations, the .30 Newton is a big-eased, unbelted cartridge that achieved some notoriety in the teens and twenties, but failed along with Newton’s several rifle-making ventures (April 2001, p. 58).

The .30 Newton was red-hot for its day, pushing a 180-gr. bullet at 2860 f.p.s. In fact, it was in many ways a better cartridge than the first fast .30 that did become a commercial success. That was, of course, Holland & Holland’s Super .30, the cartridge we know today as the .300 H&H Mag., introduced in England in 1925 and loaded by Western Cartridge Co. later that year. For more than 40 years the H&H was the standard answer for a .30 cal. faster than the ’06-but it wasn’t alone for long. Wildcatters soon discovered that its tapered case could be blown out, greatly increasing powder capacity. Roy Weatherby’s.300 Wby. Mag., developed in 1944 and brought out in factory form in 1948, was just one of several “improved” versions of the H&H-but it became a world-wide standard as a long-range, go-anywhere, do– anything hunting cartridge. To this day, it remains the flagship chambering of Weatherby, Inc., and is also offered by numerous other manufacturers.

In 1963, Winchester brought out its .300 Win. Mag. It was not and is not as fast as the Weatherby, but with its 2.5″-long case it was able to fit into .30-’06-length actions, while the 2.8″-long cases of the.300 H&H and Weatherby needed .375 H&H-length actions. In time, the .300 Win. Mag. became the second-most-popular belted magnum in the world. The .300 H&H dwindled considerably in popularity, and in time seemed relegated to the ranks of nostalgic cartridges. That made the world of fast .30s quite simple for at least 25 years. Sure, there were (and always will be) lots of wildcats, but if you wanted a factory fast .30, you chose either a .300 Win. Mag. or a .300 Wby. Mag.

Then came the 1990s. Suddenly there were new families of proprietary cartridges: Dakota Magnums, A-Square Magnums, Lazzeroni Magnums, Jarrett cartridges. Each had its .30, such as the .300 Dakota Magnum, A-Square’s .300 Pegasus, and the .300 Jarrett. Lazzeroni had two, the long-cased 7.82 (.308) Warbird, and the short-cased 7.82 (.308) Patriot. The majors were in there pitching, too. Weatherby brought out its behemoth .30-.378 Wby. Mag., Remington brought out its .300 Rem. Ultra Mag. while Winchester developed a short, unbelted case and countered with the.300 Winchester Short Magnum (WSM). Remington rebutted with its own .300 Rem. Short Action Ultra Mag. (SAUM). Suddenly, the world of fast .30s was complex and diverse … and rumor has it that even more fast .30s may be under development. Let’s see if we can sort through the confusing world of .30– cal. magnums as it stands at the close of 2001.

Levels of Performance

There was a time when the performance lines were pretty clear: The .300 Win. Mag. and the old.300 H&H Mag. propelled a 180-gr. bullet at 2900 to 3000 f.p.s., while the .300 Why. Mag. was much faster at something over 3200 f.p.s. for the same bullet weight. New cartridges, new loads, and new propellant powders have muddied the waters today.

Too, there is always a difference between published factory ballistics and reality. Today, almost every serious shooter has access to a chronograph, so most published data is about as honest as it can be. Still, the actual figures depend considerably on who is doing the loading and which rifle is doing the shooting. While all factory loads can be considered safe in sound rifles properly chambered to the correct cartridges within product lines there are performance differences, such as Federal’s High Energy and Hornady’s Light/Heavy Magnum ammunition.

Individual rifles also can make a huge difference. An obvious difference is barrel length. The norm for quoted figures is a 24″ barrel-but some companies quote data from a 26″ barrel. Reloading manuals also vary in barrel lengths used for test data, so ballistics comparisons are often skewed. Then there is the mysterious phenomenon of “fast barrels” and “slow barrels” for any caliber and chambering. No barrel is perfect, and no two barrels are identical, which may or may not affect accuracy, but will alter velocity.

Velocity variances between seemingly identical rifles can easily exceed 100 f.p.s., so there is no way to know exactly what velocity you are getting unless you chronograph that load in that rifle. And of course, with handloads, it also depends on who is doing the loading and the tolerances of a given rifle-which also vary randomly. But even within this blurry mess I think it is possible to sort out three different levels of magnum .30– cal. velocities. In that context, there are several fast .30s that produce (depending on the gun and load) between 2900 and 3100 f.p.s. with a 180-gr. bullet. There are several more capable of taking a small but distinct step upward, producing between 3100 and 3300 fp.s. with same bullet weight. And then there are just a couple of red-hot numbers that exceed 3400 f.p.s. with a 180-gr. bullet. I tend to think in terms of 180-gr. bullets, because it’s the most versatile bullet weight, but at each step, higher velocities are attainable with lighter bullets while heavier bullets is will be slower.

At this writing the most popular cartridge in the first tier is the .300 Win. Mag. It has been joined by the .300 Winchester Short Magnum (WSM), which essentially duplicates standard .300 Win. Mag. velocities in a short, fat case. The .300 WSM has created a great flurry of well-deserved interest; it is extremely accurate and wonderfully efficient, producing genuine “magnum .30” performance from a short-action rifle. It’s just too early to predict its ultimate popularity.

The.300 H&H Mag. is similar to the.300 Win. Mag. in performance, except that it requires a fulllength (.375 H&H) action. It has languished for decades, but seems to making a small but surprising comeback. There are several reasons for this. Among them is that the H&H, although archaic in case design and clearly surpassed in performance by many cartridges, is still an extremely effective cartridge. Its tapered case allows exceptionally smooth feeding, and it has strong traditional and nostalgic appeal.

There are others, of course. There are still a few .30 Newton rifles in the woods, and the .308 Norma Mag. is still loaded by Norma. The Norma is ballistically identical to the .300 Win. Mag., but has a longer neck than the Winchester, so it is theoretically more accurate and easier to handload. But the common choices among the “fast” .30s are .300 Win. Mag., .300 H&H Mag. and .300 WSM. The .300 Win. Mag. offers the greatest choice in factory loads and load recipes, and is chambered in the most rifles. The .300 WSM is too new to be offered in a great variety of loads, and its short case cannot equal the fastest .300 Win. Mag. loads-but it’s a neat cartridge with the clear advantage of fitting in a light, trim, short-action rifle. Only a handful of comparatively mild factory loads remain for the .300 H&H, so it’s primarily a handloader’s cartridge today. Mind you, with good handloads in modern actions it is capable of exceeding .300 Win. Mag. velocities.


For a generation, this group has been dominated by the .300 Wby. Mag. It remains the most popular, but today there are a few other choices among proprietary and wild-at cartridges. Of them, the .300 Dakota Magnum, based on the fatter .404 Jeffery case, produces velocities very similar to the .300 Wby. Mag. cartridge, but is able to be housed in a smaller, .30-’06-length action, while the Weatherby needs a .375 H&H-length action. Lazzeroni’s very short and still-fatter Patriot cartridge goes a step farther, producing velocities very close to that of the .300 Wby. Mag. in .308 Win.-length actions-with superb accuracy as a bonus. Then there’s Kenny Jarrett’s .300 Jarrett, similar to the .300 Why. Mag. but taken from the 8 mm Rem. Mag. case and designed to enhance accuracy.

All of those are very good cartridges, hampered primarily by availability of rifles and ammunition. The first cartridge to seriously compete with the .300 Wby. Mag. is Remington’s .300 Ultra Mag. Case length is about the same, thus requiring a .375 H&H-length action, but the Ultra Mag is based on the fatter .404 Jeffery case with rim rebated to 0.532″. Case capacity thus exceeds that of the .300 Wby. Mag. by some margin. Actual velocities depend on whose loads you’re using; Weatherby quotes 3240 f.p.s. for its factory 180-gr. load, and while Federal has a High Energy .300 Why. Mag. 180gr. loaded at 3330 f.p.s. Remington quotes 3250 f.p.s. from the Ultra Mag with 180-gr. bullets, so on the surface, it appears the Ultra Mag and the Weatherby are about the same.

However, it depends on who is doing the loading, barrel length and so forth. My experience is that Remington is historically conservative in its factory loads, but there are other loads coming down the pike that should increase Ultra Mag velocities at least a bit. More telling, there are very few .300 Why. Mag. load recipes that deliver more than 3200 f.p.s. with a 180-gr. bullet. There isn’t yet a great deal of loading data available for the Ultra Mag cartridge, but it does have greater powder capacity than the Weatherby. In time, I am sure that most loading manuals will reflect– with good handloads-a 50 to 100 f.p.s. velocity edge in favor of the Remington cartridge.

Roy Weatherby himself experimented with a .30-caliber cartridge based on the big .378 Wby. Mag. more than 40 years ago. The .30-.378 Wby. Mag. became a fairly common wildcat, but was disqualified as a potential factory round because it was too finicky with propellants then available. New powders made it viable, and the .30-.378 Wby. Mag. appeared in factory form about five years ago. It is demonstrably faster than the “fastest” group, with factory loads producing 3450 fp.s. from a 26″ barrel.

It is not alone. Lazzeroni’s large– cased, unbelted 7.82 (.308) Warbird is rated at the same 3450 fp.s. with 180-gr. Lazzeroni factory loads. Over my chronograph, by the way, those figures are a bit conservative. The potential accuracy and performance of those big cases, however, really scream for careful handloading. I hear all kinds of velocity claims for the .30-.378 Why. Mag. and 7.82 Warbird, and also for A-Square’s big.300 Pegasus (no longer manufactured at this writing). How fast they can get, and which is the fastest, really depends (again) on the rifle and the load. All are clearly capable of pushing a 180-gr. bullet more than 3500 f.p.s.-and I have seen a 7.82 Warbird exceed 3600 f.p.s on my chronograph!

All of these cartridges require extra– large actions, which means more gun weight and more expense– and all do their best with extra-long barrels, 27″ or, even better, 28″. Gun weight and barrel length are a problem in some hunting settings and not in others, but there is also the small matter of a whole lot more recoil. So the “fastest .30s” aren’t for everybody, nor for all hunting purposes-but in my mind they are absolutely the best mechanism there is for projecting a lot of energy a long distance downrange.

Which One for You?

Realistically, any of them … or none of them. Like most Americans, I love my .30s-but I’m a big fan of the .30-’06. Under most circumstances the “slow, old” .30-’06, 180-gr. bullet at maybe 2800 f.p.s., will do everything I (and probably you) need a .30-cal. rifle to do-with less kick and all the other baggage. Still, I like performance just as much as everybody else. I have a .300 Win. Mag., a .300 Wby. Mag., and a 7.82 Warbird among my personal battery. All shoot extremely well. Any of the three-or any of the fast .30s I’ve talked about-carry a good deal more energy downrange than my ’06, and they take much of the guesswork out of “medium-to-long” range shots from, say, 300 to 400 yds.

I am not a serious long-range shooter, but I have used my .30-’06’s and all three of the magnum .30s I mentioned (plus some others) to take game cleanly at distances well beyond 400 yds. Regardless of what you’re shooting, including the .30-.378 Wby. Mag. or the 7.82 Warbird, once you get on the far side of 400 yds. you still must have an increasingly precise knowledge of the distance, and you must know the cartridge’s trajectory. Putting things together at such distances therefore requires skill born of practice, and no magnum .30 (or anything else) can take the place of oldfashioned marksmanship.

That said, the magnum .30s, in ascending steps from fast to faster and fastest, project more energy downrange, and they extend the window of shooting without figuring holdover. So they are, all of them, extremely useful and versatile cartridges. Although far more powerful than is really needed, they can reach across the open plains for pronghorn or other plains game, and they can reach across the canyons for sheep or goats. They can handle any deer in any habitat, thick or open, and they’re excellent for elk or moose-also in any habitat. With heavy bullets, they go all the way up to big bears and the largest African antelope. To my mind, the magnum .30s are the most versatile cartridges in the world. They are far better for larger game than any 7 mm or lesser caliber, and while they aren’t as good as the .33s for elk or bigger game, they are much easier to shoot well. Which one is best for you-and whether you need one or not-depends somewhat on where and what you hunt, whether you handload or not and how much recoil and gun weight you are comfortable with. But there are no bad choices in the entire group.

Copyright National Rifle Association of America Dec 2001

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