.300 Win Mag Wins

The .300 Winchester Magnum may not be the best “fast .30”…but it’s the one that makes sense.

Left to right: .300 WSM, .300 Win Mag, .300 Wby Mag, .300 RUM, .300 Jarrett. These are just a few of many “fast .30” cartridges. The .300 Win Mag is not the fastest and may not be the best, but it is by far the most popular and most available.

Few cartridges are more useful and more versatile than a fast .30-caliber. They’re not perfect for all situations, for sure, however, a fast .30-caliber is pretty hard to beat. I’m thinking of the entire class of larger deer, sheep and goats; the full families of elk, red stag and moose; and the full range of African plains game. Couple this broad spectrum of game with the unfamiliar terrain and conditions we traveling hunters subject ourselves to, and a magnum .30 is a wonderfully versatile tool. Velocity is really just a number, and the race isn’t always to the swift, but if you can get a 180-grain .30-caliber bullet up above 3,000 feet per second, there isn’t much you can’t accomplish at any sensible range.

Yes, I know, the fast 7mms have their proponents. However, I believe this is offset by the .30-caliber’s larger frontal diameter, which transfers more energy and creates a larger wound channel. Also, if you know larger game is in the offing, you can step up to 200 or even 220-grain .30-caliber bullets — impossible options in 7mm. To me this is “case closed.”

Twice in the past couple of years, I’ve done two “sheep-grizzly” combo hunts, one in Alaska and one in Armenia. I know that I don’t really need a fast .30-caliber for a Dall sheep or Armenian mouflon, but add in an interior grizzly or mid-eastern brown bear and the game changes. Both times I carried a fast .30, the first time with a good 180-grain bullet, the second time with an equally good 200-grain bullet. I was ready. In August 2017, I’m trying Alaska’s Brooks Range again, hoping for better weather, and again I’m going to carry a fast .30 with a 200-grain bullet that’s aerodynamic, heavy-for-caliber and of stout construction. I simply can’t think of a better choice for such disparate game.


One of the advantages to the .300 Win Mag is its popularity: It’s made by everyone, with a wide choice in brands, bullets and loads.

There are lots of fast .30-caliber cartridges. I’ve used most of them and all are good. The lineage of the .30-caliber goes back to the British .303 (1888), actual diameter .312; and the American .30-40 Krag (1892), actual diameter .308-inch. Note that if we rounded properly, both are actually “.31-caliber” diameters. The American .30-03 came along in 1903 and its successor, the .30-’06, is the revised “.30 Government Model of 1906.” The .30-’06 was (and is) so successful that almost all the “.30-calibers” that followed used the American .308-inch (7.62mm) bullet diameter.

That includes the British .30 Super, or .300 H&H Magnum, introduced in 1925 and the oldest “fast .30” that is still with us today. In using the American .308-inch diameter instead of their homegrown British .312-inch diameter, Holland & Holland made an unstated tip of the hat to the .30-’06 in favor of their beloved .303 British. Roy Weatherby developed his .300 Weatherby Magnum in 1944, and commercial ammo has been available since 1948. Essentially just one of several “improved” versions of the .300 H&H with sharp shoulder and body taper removed, the .300 Weatherby Magnum became—and remains—a sound option for a fast .30. However, from 1925 to 1963 the .300 H&H reigned supreme as the standard and most popular “fast .30” cartridge.

In 1963, Winchester essentially replaced the .300 H&H with the .300 Winchester Magnum (“Win Mag”). Similar in potential velocity, the .300 Win Mag uses the same .375 H&H parent case blown out and necked down, but shortened to 2.62 inches so it can (just barely) be housed in a .30-’06-length action, while the H&H requires a longer (and heavier) .375-length action.

The .300 Win Mag was successful from the very beginning, but not without reservations. Techno-geeks complained that its .264-inch neck was too short to properly grip bullets, thus accuracy was reduced. This was done to maximize powder capacity in a case that could fit into standard-length (.30-’06) actions—but the short neck does indeed go against cartridge design theory, which suggests that a “proper” cartridge should have a “full-caliber” neck (in this case that would be .308-inch) to properly grip bullets.

The .300 Win Mag also suffered initially from Winchester’s unpopular shift, just a year later, from “pre-1964” to “post-1964” production. Over time, it overcame those challenges. By the 1990s, it was the second-most popular cartridge in the world to carry (or deserve) the “magnum” suffix, second only to the 7mm Remington Magnum.

Although only rarely used in competitive shooting, by then it was seeing limited use in the sniping and special operations communities. Military use increased from the First Gulf War to the present. Today, the .300 Win Mag is a fairly common choice for NATO snipers. It may not remain so, as much development is ongoing with more modern case designs (such as the .300 Norma Magnum), but over the past 20 years, its fame as a sniper’s cartridge has silenced most remaining reservations: The .300 Win Mag has become the most popular “magnum” cartridge in the world. The 7mm Remington Magnum has dropped to a distant second place, and the .300 Win Mag far surpasses all .30-caliber competitors and all other 7mm cartridges.

Today there are lots of fast .30s, and the .300 Win Mag is not the fastest. The .300 Weatherby Magnum still beats it. Based on case capacity the .300 Remington Ultra Mag (RUM) is a bit faster yet, and the huge-cased .30-.378 Weatherby Magnum is quite a bit faster. There are also other limited-production (wildcat, proprietary or single-source) fast .30s that are either very similar or faster, but with theoretically “better” case designs. The list is long but might include the .300 and .308 Norma Magnums, .300 Blaser Magnum, .300 Dakota Magnum, .300 Jarrett, .300 Tejano, Lazzeroni’s 7.82mm (.308) Warbird and more.

A single 200-grain ELD-X bullet from a .300 Win Mag accounted for this kudu.

There is also a significant family of short .30-caliber magnums, based on fatter cases and designed to fit into short (.308 Winchester family) actions. Those include the .300 Winchester Short Magnum (WSM), .300 Remington Short Action Ultra Mag (RSAUM), .30 Ruger Compact Magnum (RCM), and Lazzeroni’s proprietary 7.82mm (.308) Patriot. These short magnums are efficient and their ability to be housed in a lighter and more compact action is seductive—but case capacity eventually tells. The three commercial short .30s (WSM, RUM, RCM) do not quite come up to .300 Win Mag velocities. The Patriot, with a still-fatter case, definitely does, but only a handful of actions are wide enough to handle it. Performance-wise, however, all the short .30s are actually fast enough, and come close enough to .300 Win Mag performance that velocity alone is not a sound argument.


Interestingly, the first “fast .30” I ever owned was a .300 Win Mag obtained in the early 1970s. A Mauser Mark X action in good walnut, it shot well but for unknown reasons I never actually hunted with it. Along with everything else, it was stolen in about 1981, and one of the first replacements I acquired was a left-hand Weatherby Mark V in .300 Weatherby Magnum. With few other choices, I hunted with it a lot over the next few years and became very familiar with it. To this day, the .300 Weatherby Magnum remains a primary “default setting.” In addition to Weatherby rifles, I have a long-favored Rifles, Inc. .300 Weatherby Magnum on a left-hand Model 70 action, and a much-used .300 Weatherby Magnum barrel for my Blaser R8.

I concede that there are faster .30s, and I’ve used most of them. Among factory cartridges the .300 RUM is probably “better,” but not by enough margin to make me shift. Also, although I’ve used a bunch of them, both as a gunwriter and a traveling hunter, I’ve found limited-source and single-source cartridges sometimes awkward to use, and for sure I don’t handload as much as I used to.

A very good Quebec-Labrador caribou taken with an MGA in .300 Win Mag. Although exceptionally light, this rifle is very accurate. Boddington used it quite bit, but because of its light weight it needed its muzzle brake and the blast was extremely loud.

I have also used all of the short .30s. They are efficient and they are accurate, but (excepting the Patriot) they don’t quite equal .300 Win Mag performance. Most have the same single-source or limited-source ammo availability and they have one more vexing problem: Their short, fat “fireplug” case design is efficient and modern as tomorrow, but most bolt actions have been with us for a while and are not as modern as tomorrow. Few bolt actions were designed to house short, fat cartridges so smooth feeding is a frequent problem.

Enter the .300 Win Mag. Cartridge popularity is not really a bad thing, especially for traveling hunters. The .300 Win Mag is made by everybody, both rifle and ammunition manufacturers. It has generally not been my preference, but as a gunwriter I’ve found it almost unavoidable. This is especially true as a left-handed gunwriter! Most companies that make left-handed rifles offer very limited chamberings, but you can figure .300 Win Mag will be among them, and obviously it’s available in almost all right-handed rifles. So, over the years, I’ve used and written about a lot of .300 Win Mag rifles, both right- and left-hand actions, from a variety of makers.

Accuracy has ranged from spectacular to plenty good, but has never been an issue (despite the long-maligned short neck). One of the most accurate sporting rifles I ever used was a wood-stocked .300 Win Mag by Glendale, California riflemaker Ray Riganian — a real tackdriver. But a super-light MGA .300 Win Mag was very accurate, likewise a Legendary Arms Works (LAW) 704, and my Kenny Jarrett Ridge Walker is extremely accurate — all these in .300 Win Mag. And I really shouldn’t forget a Krieghoff Semprio slide-action .300 Win Mag; although seemingly unlikely, it’s another tackdriver.

Realistically, however, I remain convinced that quality of barrel, precision of assembly and bedding, and consistency of ammunition are far more important to rifle accuracy than the design of the cartridge case. So I’m not prepared to say that the .300 Win Mag is more accurate than any of the other fast .30s. Due to its popularity, it has an advantage in that so many loads are available, including some match loads. However, with rifles and barrels of equal quality and precision handloads, some of the other fast .30s should be on-average more accurate (and some might be worse). I think it would take an awful lot of shooting to prove it, and in the context of hunting, the difference is unlikely to be significant: All the fast .30s are accurate enough.


Although the .300 Win Mag has not been Boddington’s choice until recently, as a gunwriter it’s an unavoidable cartridge, used in many rifles over the years. In Tanzania in 1993, he used a wonderfully accurate Dakota M76 .300 Win Mag to take a variety of game, including this fine sable.

Like I said, I’ve long been a dedicated .300 Weatherby Magnum guy, so this has not been an overnight revelation and it’s kind of a bitter pill to swallow. Some years ago I used the MGA .300 Win Mag quite a lot. It was light and accurate, but I stopped hunting with it because the muzzle brake (which this six-pound rifle needed!) was too brutal. I went back to the .300 Weatherby Magnum with 26-inch barrel. Two recent events have changed my thinking. First, I had the Mark Bansner-built LAW M704 as a TV show sponsor, meaning I was obligated to use one of their rifles while filming. Although right-handed, it’s a great rifle, shot straight and happened to be in .300 Win Mag. I used it a lot, and very happily. Second, Kenny Jarrett built me one of his medium-weight Ridge Walkers on his left-hand receiver. Somehow we got our signals crossed; I was actually expecting a .300 Weatherby Magnum, but it arrived as a .300 Win Mag with 24-inch barrel.

With Leupold’s CDS (Custom Dial Sytem) scope turrets it’s essential to chronograph the loads, which can be revealing. Norma’s .300 Weatherby loads are rated up to 3,250 fps with 180-grain bullets in 26-inch barrels, but domestic .300 Weatherby loads aren’t that fast, often not much over 3,100 fps. With new propellants, velocities for .300 Win Mag loads have crept up. I can get a solid 3,100 fps from the .300 Win Mag with 180-grain bullets in a 24-inch barrel, either from handloads or select factory loads. The difference isn’t enough to argue about, and the .300 Win Mag not only requires a shorter barrel; it also uses a shorter, lighter and more compact action. So, for a maximum difference of little more 100 fps—often a lot less—I can shave considerable gun weight. My Jarrett .300 Win Mag is no lightweight, but with a VX-6 3-18X and Talley mounts, it weighs 8.5 pounds. My Rifles, Inc. in .300 Weatherby with 26-inch barrel and the same scope weighs about 10 pounds. When I was younger, I didn’t care so much about gun weight. Today it’s starting to matter!

Obviously, the .300 Win Mag wins in terms of availability of ammo and variety of loads and bullets. There are dozens of factory loads from all makers. You can get Barnes and Nosler bullets from multiple sources. You can get Swift A-Frame and Scirocco, including in their new High Grade factory ammo. You can get Hornady and Sierra, or the full range of Federal, Norma, Remington and Winchester bullets.

Boddington used an LAW in .300 Win Mag to take this aoudad in west Texas. These are among the biggest and toughest of the sheep/goat clan, and a fast .30 is definitely a good choice.

There is something you can’t get: There are no 220-grain .300 Win Mag factory loads from major suppliers. This is because Cartridge Overall Length will be a problem in some .30-’06-length actions and magazine boxes. You can get .300 Weatherby Magnum and .300 RUM with 220-grain bullets — not a problem in .375-length actions. If you want these extra-heavies in your .300 Win Mag you’ll have to handload them yourself, or go to a custom loader…but they may need to be seated deeply in order to function, which may rob powder capacity and reduce velocity.

I don’t see that lack as a major loss. Bullets today are far better than they used to be, and you don’t need as much weight as we once did to overcome sins in bullet design. There isn’t much you can’t do with a modern 180-grain .30-caliber bullet, but you can hedge your bet a bit with a 200-grain bullet in the .300 Win Mag. In Africa, I’ve been using Hornady’s Precision Hunter load with 200-grain ELD-X. In .300 Win Mag, this load is rated a bit slower — 2,850 fps. However, barrels vary, and my Jarrett has a fast barrel: It consistently delivers more than 2,900 fps with that load, which combines exceptionally aerodynamic shape with good terminal performance and the extra weight. Last year I took a quartering-away shot on an eland with that load in the Jarrett .300 Win Mag. The eland is a very large animal for any .30-caliber, but it was down in 40 yards. That’s the setup I’m carrying in August for another Dall sheep-grizzly combo. It’s a backpack hunt so I’m happy to shave a bit of weight. It will get the job done just fine!


3 thoughts on “.300 Win Mag Wins”

  1. Another excellent article, Craig. I’m struggling to find anything to nit-pick or complain about. But, then again, I’m also partial to the fast 30’s.
    Hopefully, you didn’t have to work on Christmas day to make your deadline!

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