.30-06 Springfield vs .308 Winchester: Ballistic comparison
If there has been one constant in the gun world, it’s Americans’ love for .30 caliber. This relationship even predates smokeless powder with the 30-40 Krag first being produced way back in 1892! While the Krag cartridge had a short service life, Americans saw the potential for this caliber and continued developing better cartridges around 308 bullets. Two of the most popular 30 cal cartridges are the 30-06 and 308.
The .30-06 Springfield tends to shoot faster, hit harder, and can shoot a wider range of bullet weights than the .308 Winchester. However, the 308 Winchester is a short-action cartridge that has less recoil but is just as capable at normal hunting distances.
It’s important to keep in mind that while we’ll be taking an in-depth look at the differences between the 30-06 and the 308, the two cartridges are far more similar than fans of one or the other would have you believe. After all, the 308’s military equivalent, the 7.62x51mm, was designed to replace the aging 30-06 in the 1950s.
With today’s bullet design and powder mixtures, both cartridges can shoot faster and hit harder than their original loads, so both are quite capable of killing big game. In the case of 308, some people regularly use this cartridge to kill animals up to the size of an elk (cough, Randy Newberg, cough). Meanwhile, the 30-06 has been used to kill just about every game species on the planet.
The utility of both cartridges is what makes this comparison so interesting. Both are ‘generalist’ cartridges that can be used to hunt a variety of game, yet they accomplish this with different approaches. To understand the Springfield and the Winchester, we’ll take a look at their history and uses. However, our ‘deep dive’ will be into the ballistics of the 30-06 and 308.
What’s interesting when comparing the 30-06 and the 308 is not their differences but rather their similarities. Looking at the table below, we can see the average figures derived from several loads for each cartridge. Don’t worry about keeping track of all these numbers! I’ll do a final tally at the end of this article on the various pros and cons of each cartridge.
|Cartridge||Average Bullet Weight (grains)||Muzzle Velocity (fps)||Muzzle Energy (ft-lbs)||Free Recoil (ft-lbs)||Recoil Velocity (fps)||Distance to 1500 ft-lbs (yards)|
When it comes to bullet weight, the 30-06 and 308 tend to shoot bullets in similar weight categories. However, the 30-06 tends to shoot, on average, a slightly heavier bullet. For our data, that’s a difference of only 3 grains. The data doesn’t tell the whole story though. While the Springfield can shoot up to 220gr bullets reliably, the 308 tends to top out at 190gr. Both are most popular with 150-165gr spitzers.
The powder capacity, combined with the average bullet weight is what gives us any notable differences between the two cartridges. While the 308 has less free recoil on average, 18.27 ft-lbs versus 21.34 ft-lbs, and slower recoil velocity, 11.62 fps versus 12.55 fps, the 30-06 has slightly more bullet velocity, giving it an energy advantage at the muzzle of 404 ft-lbs.
This is because while adding weight increases energy linearly, adding velocity increases energy exponentially. Energy is equal to mass multiplied by the square of velocity, so a little more speed goes a long way! We can see this in the distances to below 1500 ft-lbs of energy, the recommended minimum to kill elk-sized game. The 308 has a respectable range of 485 yards, but the 30-06 can reach out to 603.
While looking at some of the basics goes a long way, there are some other ballistics figures to consider. Long-range capability is something many of today’s hunters want to consider. So, let’s compare these two old warhorses to the thoroughbreds of the 21st Century.
|Cartridges||Year Introduced||Bullet Drop 500 Yards (inches)||Bullet Drop 1000 Yards (inches)||Wind Drift 500 Yards (inches)||Distance to 1900 fps (yards)|
The common pattern seen in this chart is that the higher B.C. bullets, combined with speeds north of 3,000 fps out the muzzle, yields fantastic improvements for bullet drop and retained speed (and energy). Wind drift is about the only metric here that hasn’t been improved on much, with only a 4.4 inch variance between the 308 and the 300 PRC.
The metric which matters most here is the distance to 1,900 fps. At around that speed, bullets usually don’t expand reliably when impacting the flanks of a big game animal. Without expansion, the animal will only have a 30 caliber hole punched into it which does a lot less damage to organs. This means animals shot in such a manner will bleed out slower, something no hunter wants to deal with.
In this regard, the 300 PRC has a 219-yard advantage over the 30-06 and a 321-yard advantage over the 308 Winchester. As long-range cartridges go, this is a distinct advantage for killing big game. It’s one thing to be able to hit an animal at 700 yards, but it’s another thing entirely to kill it.
Most hunters are simply not capable of reliably killing game at such distances. Anyone can learn these skills, but it takes practice and instruction, something many hunters don’t get enough of. For those of us who haven’t extensively practiced, 500 yards is about the limit, and being within 400 yards is preferred. It is here we can say that having a 308 and a 30-06 is not only acceptable but could very well be superior.
That’s because the cost of those big 30 cal cartridges is recoil energy. The 30 Nosler and 300 PRC both have recoil greater than the 300 Win Mag, considered by many hunters to be a heavy-recoil cartridge itself. By comparison, the 30-06 and the 308 are quite manageable, leading to greater accuracy. For most hunters then, these two older cartridges would serve them better.
Neither cartridge can really be considered for long-range hunting by modern standards, but the 30-06 does have an advantage. If you’re like me and purchase most guns from a pawn shop, then a 30-06 will give you greater reach over a 308. Again, relative to other options the differences aren’t that great, but there are differences nonetheless.
Energy and Velocity
|Cartridges||Energy 100 Yards (ft-lbs)||Energy 500 Yards (ft-lbs)||Energy 1000 Yards (ft-lbs)|
|Cartridges||Velocity 100 Yards (fps)||Velocity 500 Yards (fps)||Velocity 1000 Yards (fps)|
Now that we’ve established their range limitations compared to more modern cartridges, we can better compare the 30-06 and the 308 against each other for energy and velocity. For many people, these two metrics are the easiest to understand and the most useful for direct comparison.
To make these charts, I plugged in the data gathered by the Backfire team for bullet weight and velocity and ran it through a ballistics calculator. I used a 100 yard zero, kept the G1 B.C. identical at 0.48, and assumed a 10 mph crosswind. Readers should be able to replicate these figures or get very close, in any ballistics calculator.
The 30-06 has an advantage for both velocity and energy, and this is because one leads into the other. However, these differences are due to the increased case capacity of the 30-06. The Springfield case holds 68 gr of water while the Winchester holds 56 gr according to SAAMI specs. These differences show that while the 30-06 is faster and more powerful, the 308 seemingly does something rather remarkable.
From 100 to 1,000 yards, the Winchester manages to deliver 98% of the bullet mass with 87% of the Energy and 94% of the velocity of the 30-06 in a case that’s 18% smaller and with 16% less recoil. The difference in velocity, and the difference in bullet mass, is what makes up the difference in energy. That adds up, what doesn’t add up is the velocity compared to the case capacity.
Capacity and Pressure
|Cartridge||Case Water Capacity (gr)||Max. Pressure (PSI)|
Anyone who had an economics class in school will be familiar with the law of diminishing returns. Physics has a similar issue in that to double the speed of an object, four times the kinetic energy is needed. So how’s it possible then that, on average, a 308 can get so close to replicating the 30-06 velocities using less case capacity?
The answer to that is twofold. First, the 308’s pressure rating is 62,000 PSI according to SAAMI. The 30-06 is limited to 60,000 PSI. 308 cases will therefore handle a hotter load, relative to 30-06 cases. This means that while the case volume is less, both cartridges can use a similar powder load. We can therefore say that the Winchester has a more efficient case design compared to the old Springfield.
Re-loaders will notice this because, assuming both cartridges are being loaded to be equally ‘hot’, number of rounds that can be filled with a lb of powder will be nearly identical. With maybe two grains of powder difference, (42gr vs 44 gr), 1lb of powder would charge 166 rounds of 308 vs 159 rounds of 30-06.
Where the 308 really shines is that it can be loaded up to perform at or near the same level as the 30-06, reducing any advantages to being marginal. Where the 30-06 shines is that extra length allows for a wide variety of bullets to be seated inside the case.
There have been many articles (if not books) written on the history of these two cartridges so I won’t waste much of your time rehashing that history. Yet understanding how the 30-06 and 308 rose to prominence is important, so consider this a brief summary.
As the name suggests, the 30-06 Springfield was a 30 caliber cartridge first produced in 1906. The US military was looking to improve on its previous 30-caliber cartridges, starting with the 30-40 Krag in 1892 and ending at the time with the 30-03 Springfield in 1903. The progression of these early 30 caliber cartridges built a solid foundation for the development for the 30-06.
After some experimenting with the 30-03 cartridge, the 30-06 was born. The ’06 used a lighter, 150gr ‘spitzer’ type bullet compared to the 220gr ’round nose’ of the 30-03. The case was also shortened by 2 mm from 65mm to 63mm. The result was one of the most successful cartridges in the 20th Century.
The Springfield 1906 cartridge went on to victory in both world wars and saw extensive use in Korea and the early Cold War period. The first military-issued rifles chambered for the 1906 cartridge was the M1903 Springfield which was re-chambered from the 30-03, followed by the M1917 Enfield, the M1 Garand, Browning Automatic Rifle (BAR), and numerous other rifles outside the US.
Almost from the start, the 30-06 was a beloved cartridge by hunters. As its reputation grew on the battlefield, so did its reputation with big game hunters all over the world. The ’06 has been used to hunt just about every game species on the planet, from coyotes to Elephants. While some of these feats don’t hold up to today’s ethics, it’s common to see this old cartridge used when hunting moose, elk, and bears.
The .308 Winchester originally started as a wildcat variant of the 300 Savage. However, Winchester decided to adopt the cartridge as their own and first produced loads for civilian purchase in 1952, two years before the US military adopted a very similar variant called the 7.62x51mm.
The idea behind the 308 was to achieve similar killing power to the famed 30-06 in a compact cartridge. Why go smaller? For one, the 308 uses less brass and powder, making the cartridges slightly cheaper per round. The main reason, however, is weight and volume savings. While a hunter might not feel the difference with a handful of rounds, the difference is profound with military logistics.
The 7.62x51mm had its share of popularity in the military, but that story falls outside the scope of this article because it is technically a different cartridge. Anyway, the 308 Winchester quickly became a popular big game cartridge in its own right. In North America and Europe, the 308 has been used to hunt every big game species on those two continents.
Today, the .308 remains one of the most popular hunting cartridges on the market. However, while some claimed this cartridge to be a ’30-06 killer’, the Springfield has refused to die. While both cartridges might be declining slightly in popularity with the new craze of high-B.C. bullets, fast twist barrels, and even more efficient cartridges, neither the Springfield nor the Winchester is on the path to extinction.
Uses for the 30-06 Springfield
The best thing about the 30-06 is its bullet versatility. This is the ace the ol’ Springfield has kept in it’s hand since the beginning. Animals down to the size of coyotes can be taken with bullets as light as 87 grains. At the same time, killing animals up to the size of moose and brown bears is possible with heavy bullets. The heaviest I’ve been able to reliably find is 230 grains in weight.
Whether a particular rifle can handle that range of bullets or not is a different story. A slower-twist barrel with reduced powder loads will accept the sub-100gr bullets but that same rifle is unlikely to accept 200+gr bullets with hot loads. This isn’t an article on rifles though, so that limitation is irrelevant here.
As a general-purpose rifle, the 30-06 has a pretty significant advantage. It is unlikely that a hunter would find themselves in a location where 30-06 ammo couldn’t be sourced. This cartridge has been used to hunt everything on every continent and there are millions of rifles around the world chambered for this cartridge.
Uses for the 308 Winchester
While the 308 is largely successful at closely replicating 30-06 killing power in a smaller package, it simply doesn’t have the same history as the 30-06. Its military life is only just exceeding the 30-06, and only because the US military still has a couple of machine guns that utilize the military equivalent. The 308 came about at a time when ‘military’ cartridges were diverging from ‘sporting’ cartridges.
The Springfield might take a wider range of bullets, but Winchester’s real strength is its one-size-fits-all shooter capability. For some people, the ’06 is too much recoil and the older rifles are too heavy. Others don’t like the longer bolt throw and some poor soul lugging ammo on a battlefield would hate the extra weight.
The 308 represents an excellent balance that many shooters will appreciate. While not the preferred choice for bears and moose, it would certainly get the job done at closer ranges. Many hunters use a 308 as their primary big-game gun. With slightly less recoil, guns chambered in 308 tend to be more manageable.
Uses for both 30 calibers
As I wrote at the beginning of this article, the similarities between the 30-06 and the 308 outnumber the differences. Neither are particularly well-suited for long-range hunting and it would be a mistake to say that either is best for situations involving precision shooting when there are so many great alternatives on the market.
For hunting ungulates, the story is a bit different. Both are excellent choices for anyone living in North America, Europe, Australia, and even Africa. Where civilian ownership of guns is legal and hunting is common, both calibers can be found even in a lot of backwood towns. That assumes, of course, the whole country isn’t panic-buying anything that goes bang.
Another use that either of these cartridges fills is the person who needs, or for some reason wants, only one gun in their closet. Someone who goes hunting every year but isn’t an avid gun collector will want to look at either of these calibers. Both will work well in a variety of hunting situations and, provided a hunter’s stalking skills are up to par, both have plenty of range to work with too.
I personally see a great use for either the 30-06 or the 308, and that’s for hunting in situations requiring quick shots from a standing or kneeling position. You don’t need, or even want, a magnum for those situations and both will provide plenty of killing power compared to straight-wall cartridges or slugs.
Before diving into ballistics, I said I’d keep a tally for readers. Here’s my tally according to the data and arguments presented above:
|Advantages||30-06 Springfield||308 Winchester|
|1900 fps Range||+1||–|
|Free Recoil Energy||–||+1|
This is one of those situations where one cartridge looks like it has a bigger advantage than it does. I gave a point to each clear advantage and whenever one caliber’s advantage was marginal, I gave zero points. No matter which way these categories are counted up, the 30-06 has a clear advantage in seven of them while the 308 has a clear advantage in four.
The 30-06 has an advantage for bullet energy, roughly 13% more energy on average. The Springfield also can claim a slightly better wind drift, longer hunting ranges, less bullet drop, and greater bullet variety. Those advantages come at the cost of greater recoil and a heavier, less efficient case design.
The 308 does have better case efficiency, greater maximum pressure, less free recoil energy, and a slower recoil velocity. It seems then that the claims that a 308 is a compact, efficient cartridge are true. Its design dominated the latter half of the 20th Century and has spawned numerous wildcat designs that are still growing in popularity.
For readers trying to decide between these two calibers, I can only suggest that you, the reader, weigh each of these metrics according to your personal needs in a rifle. Don’t forget, we welcome your opinion on the matter too so feel free to comment below!