.357 Magnum vs 9mm

The Best Self Defense Load

Whether you choose to carry a semi-automatic or a revolver for your daily carry firearm, either is useless without the proper ammunition. 9mm and 357 Magnum are two of the most popular self-defense loads on the market. Knowing this, we decided to do a complete comparison breakdown between the two. GrabAGun proudly provides a wide variety of ammo deals for shooters of every caliber. We are a trusted online gun store with a large online inventory of firearms, including Glock 43 handguns for sale, revolver deals, and more. Get 9mm or 357 Magnum ammo at GrabAGun today–as soon as you’re done reading this post! 

Battle of the Ammo: 357 Magnum vs 9mm

Alright, first things first. Why even compare .357 magnum vs 9mm? Well, both are extremely popular, capable, and proven rounds. In fact, we are comfortable saying they are the best combat cartridges in their respective platforms and respective genres. The fun comes from the fact that these two calibers are very much the same but also very different. So, let’s dig in and compare these two incredible calibers. 

357 Magnum vs 9mm Specs

Specifications9 x 19 mm357 Magnum
Bullet Weight115gr to 147gr125gr to 180gr
Bullet Diameter.355 inches.357 inches
Case Length19.15mm33mm
Max Overall Length29.69mm40mm
Case Capacity13.3gr H2O26.2gr H2O
Max Pressure34,084 PSI35,000 PSI

When you start looking between the two, you’ll notice some similarities. For example, the projectile sizes–they’re almost entirely identical. The 9mm uses a .355 caliber bullet and, predictably, the 357 Magnum uses a .357 caliber projectile. On top of that, both rounds came to be for material use, with the 9mm intended for military forces and the 357 Magnum for police forces. Ultimately, both rounds have faithfully served in law enforcement roles, in concealed carry roles, and far beyond. However…

While the two have quite a bit in common, they are also two completely different rounds. The 357 Magnum is primarily a revolver cartridge, intended to provide new levels of power to the fighting handgun. The 9mm is primarily an automatic cartridge that strikes that balance between power and capacity. Since 9mm is one of the most widely used rounds, we’re going to look at that first. 

9mm, not 357 Magnum, bullets

9mm: History and Purpose

The 9mm has been around for a long, long time. While it’s the choice for modern military and police forces, the 9mm round can be traced back all the way to 1901. It was then that Georg Luger decided two things:

-He didn’t need the ‘E’ at the end of his name

-The world needed a new bullet. That particular bullet would use a 19mm and a 9mm projectile

The actual round originates from the 7.65×21 Parabellum, but the shorter profile allowed it to function better with the Luger pistols toggle lock and allowed for a more ergonomic grip. (Long rounds make wide grips and wide grips aren’t overly comfortable) Still, the round packed a sufficient-sized projectile–for the case capacity–delivering efficient energy on target. 

The 9mm round would go on to serve in World War 1, World War 2 (with the Tommy Gun), and every war since then. The cartridge became widely popular in pistols and submachine guns. Europe was actually the first to adopt the 9mm and did so with gusto. It was the official standard for both the Axis and Allies during World War 2. Fact: the Brits Sten gun faced off against the Nazi MP40 in combat, both blasting 9mm from submachine guns. The US wouldn’t get over its 45 ACP lust until the 1980s, which is when the 9mm finally became the United States standard. 

Since then, it’s become the round of choice for NATO, the United States military, and most modern police forces. These days, it’s the dominant round in the US and continues to be the round of choice for a wide variety of shooters. With over a century on the market, it’s benefited from research, design updates, and lessons learned. These include effective projectile designs involving jacketed hollow point rounds. JHPs have actually helped narrow the gap between the 9mm and larger rounds like the 40 S&W and 45 ACP. 

9mm Ammo Recommendations

When it comes time to purchase, bulk 9mm ammo is the way to go. You’ll truly get the most bang for your buck (pun 100% intended!) GrabAGun has a vast selection of 9mm ammo for sale from top brands including Winchester, Federal, Magtech, and more. What’s more, we have flat-rate shipping that will never change. So buy all the ammo you want–without breaking the bank! 

For the range

For self-defense

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357 Magnum revolver

357 Magnum: History and Purpose

Despite WWI making the automatic pistol mainstream, most American police forces continued to stick with the proven six gun design in the following years. Revolvers ruled and most utilized the 38 Special. The prohibition era followed the Roaring 20s and with it came a wave of gangsters, meaning 1930s law enforcement needed something new. 

At the time, the 38 Super Automatic was one of the only rounds that could penetrate through metal car doors with any kind of efficiency. Police wanted a revolver that could do that. Plus, bootleggers and bandits were now mobile, so that factored into development. A group of experts began experimenting with suped-up 38 Specials on 44 frames. The result was a tougher, higher velocity round that could pierce the thin metal that car doors were made from. It was Elmer Keith that worked so hard to make that suped-up 38 Special a reality. Ultimately, it was Smith and Wesson that made the 357 Magnum a reality and produced the first-ever, 357 revolver.

Immediately, the industry took notice and began producing a variety of 357 revolvers. Colt specifically, happily adopted the round in their numerous “Snake” guns. (Colt Python, anyone?) This new round was slightly longer than the 38 Special, an insurance measure done to make sure shooters couldn’t accidentally load 357 Magnum rounds and cause a handheld explosion. 

The 357 Magnum cartridge became a favorite among law enforcement at every level–state, federal, and local police forces quickly adopted it. The heavy-hitting cartridge proved quite successful and easily earned the reputation as a well-known man stopper. While revolvers and 357 Magnum have faded from duty use, it’s still a popular configuration and caliber among civilian shooters. 

357 Magnum Ammo Recommendations

As discussed, 357 Magnum is still highly popular amongst civilian shooters. It’s regarded as a quality and reliable home defense round. GrabAGun has plenty of 357 Magnum options available from a number of top-billed brands. CCI, Fiocchi, and Sellier and Bellot are just a few of the names we carry–at prices that you can get behind. Find 357 Magnum ammo deals online through GrabAGun today. 

For the range

For self-defense and home defense

The Nitty Gritty

Okay, so we’ve gone over the history for each round, but now it’s time to get down to the brass tacks. What are the differences between 357 Magnum and 9mm ammo? Let’s look. 

While both rounds offer outstanding performance for what they are, they are still very, very different. The 9mm is considered a bit of an intermediate pistol round designed primarily for automatic pistols while 357 is a heavy-hitter used mainly in revolvers. 

Ballistics: 357 Magnum vs 9mm

Specifications9mm357 Magnum
Grain124125
Feet Per Second1,1501,500
Foot-Pounds of Energy364585
Penetration (Inches)~12 ~18+
Drop (Inches)~12~4

When broken down like this, it’s easy to see that 9mm rounds are admittedly average–in terms of ballistics. It’s no 10mm nor is it 357 Magnum. The 9mm routinely reaches the FBI standards for penetration through 12 inches of ballistic gel. This means that, in a defensive scenario, this round will easily reach the vitals of a bad guy and effectively stop a threat. What’s more, because of those average ballistics, there’s no risk of overpenetration. 

357 Magnum is a completely different beast. Clearly, this round outperforms the 9mm. It has no issue meeting FBI standards and even exceeding them. The minimum is 12 inches while the maximum is 18. Go past 18 inches and you risk overpenetration. Meaning, your chances of hitting an innocent bystander or destroying property increase with such a cartridge. That’s why proper self-defense bullet selection is a must when using 357 Magnum. 

Though both rounds are meant for handguns they have also found their way into long guns. 9mm has become the caliber of choice for semi-automatic carbines while 357 works well in lever guns. It doesn’t matter which platform you choose, 357 Magnum predictably does better than 9mm. Load a Hornady Flex tip or Leverlution round and the 357 Magnum has hardly any drop out to 100 yards from a 16-inch barrel. With regular 357 Magnum ammo, you’ll usually see at least a few inches of drop at best. 

Compare that with 9mm and you’re looking at 10 to 12 inches of drop out to 100 yards as well as the potential for lots of wind drift. So, in terms of ass-kicking, there’s no question. 357 Magnum kicks 9mm butt when it comes to effective range, energy on target, and wind drift. 

Recoil & Muzzle Rise

We, clearly, established that 357 Magnum kicks butt ballistically, but as you’d imagine, you pay for it in felt recoil and muzzle rise. Before you get any ideas in your head, 357 Magnum is not some kind of crazy powerful cannon that will throw you back when you shoot it. This ain’t the movies. That said, a gun with this caliber loaded will have some serious recoil and muzzle rise compared to the 9mm. 

In a duty-sized revolver with a big, heavy frame and 4-inch barrel, the 357 Magnum is a tight shooter that’s slightly stout. Not a big problem, right? Right. There will still be recoil and muzzle rise, but it is much easier to control, especially if you are comparing it with a snub nose. Choose a 357 Magnum with a snub nose design and that gun becomes much less manageable. An air-weight snub nose is a literal handful to hold onto when you start spitting lead.

A smaller 9mm might be pretty snappy, but it’s nothing compared to a 357 Magnum snub nose. Plus, follow-up shots will always be faster with a full-sized 9mm automatic. It’s just the nature of the beast. There is something to be said, however, for a 357 Magnum’s ability to chamber a 38 Special round. Heavier frame guns can easily and safely fire the tamer 38 Special and 38 Special +P loads, making the gun much more manageable to shoot. 

No matter what, there’s no such thing as a free lunch. If you want that 357 Magnum power, you will pay for it. Higher capacity and lower recoil do have a cost. You’ll have to weigh your options to decide what would be best for you, your needs, and your situation. 

semi automatic and revolver handgun, side by side.

357 Magnum at GrabAGun

So, which is better? That’s up to you. Ultimately, the argument comes down to semi-automatic handguns versus revolvers. 9mm exemplifies everything great with a semi-automatic firearm–mild recoil, the potential for 15 to 20 rounds, and suitable ballistics backed by fast follow-ups. Of course on the flip side, the 357 Magnum illustrates the sheer, raw power a revolver can offer. The long case packs a powerful punch in such a small projectile. With that in mind, the size of the revolver you’ll need to manage all that power can be difficult to conceal. Whereas, 9mm is far more catered toward concealed carry. 

Whatever you decide, GrabAGun is here to help. We carry semi-automatic handguns, revolvers, and their respective ammo. Find a Glock 43 for sale or Chiappa Rhino revolver deals on our site right now. We are the premier online gun store with prices that can’t be beaten. Find 357 Magnum ammo deals at GrabAGun today! 

–Kellie Krevosky