For this overview, we will compare two powerhouses from the middleweight category that gain their popularity in real life, movies and TV series.
By many pistoleros, the “holy trinity” chamberings for the self-defense handguns are .357 Magnum, .45 Auto and 10mm Auto. Unlike Hollywood myths, handguns rarely can stop humans with just one round, but these three “magnificent” have a stunning track record of one-shot stops on two-legged predators.
Leaving legendary .45 ACP aside, we will search out and explain basic similarities and differences between 10mm vs. .357 Magnum for this post.
Although they were made 50 years apart, comparing 10mm vs. .357 Magnum isn’t easy since both have numerous loads that overlap in terms of power. On the other hand, comparing the 10mm Auto vs. .357 Magnum seems fair considering their physical dimensions and ballistics.
|Cartridge||10mm AUTO||.357 Magnum|
|Bullet||77 to 220 gr (5.0 to 14.26 g)||110 to 200 gr (7.2 to 12.96 g)|
|Bullet diameter||0.40” (10.16mm)||0.357 (9.07mm)|
|Case length||0.992 (31.9mm)||1.29” (32.8mm)|
|Maximum overall length||1.260” (32mm)||1.590” (40.4mm)|
|Base diameter||0.425” (10.80mm)||0.379” (9.6mm)|
|Max Pressure (SAAMI)||37,500 psi||35,000 psi|
|Muzzle Velocity||180gr/ 1,290 fps||158 gr/ 1,250 fps|
|Muzzle Energy||180gr/ 624 ft-lbs.||158 gr/ 548 ft-lbs.|
|100yds Bullet Drop & Energy||-11.3” 430 ft-lbs.||-8.5” 360 ft-lbs.|
|Free recoil energy||9 ft-lbs.||10 ft-lbs.|
|Case capacity||24.1 gr H2O||26.2 gr H2O|
If you are a handgun aficionado looking for features like Magnum, full power, and strong recoil, the 10mm Auto and .357 Magnum might be suitable for you. If you’re in the market for a defensive cartridge that can pack on the foot-pounds and FPS, look no further than the .357 Magnum and 10mm Auto.
While the older cartridge has recorded constant popularity from its very beginning with a slight decrease in the last few years, the other round recorded waning in popularity to make a comeback with more and more companies adding 10mm ammo in their catalogs.
The .357 Magnum was created in the era of Prohibition in the 1930s when the police departments needed an efficient cartridge to penetrate car doors and bulletproof vests of gangsters and armed bootleggers.
As a result of cooperation between Elmer Keith and Philip Sharp, the .357 Magnum was released in 1934 for the Smith and Wesson N-frame revolvers reserved for the .44 and .45 calibers. Hence its full name is a .357 Smith & Wesson Magnum.
In simplest words, the .357 Magnum can be described as an elongated .38 Special that packs more force behind the bullet generating greater velocity and energy. Though .357 Mag has the same diameter of the bullet as the .38 Special, due to its 1/8 of an inch longer case, it cannot be loaded into the .38 Special rated chambers for safety purposes.
As for the velocity, the original 158-gr load at 1,200-1,300 fps showed a 52 percent increase over the venerable .38 Special, which was a fantastic performance for a handgun cartridge of the time.
Compared to 10mm, the essential difference is in the arm platform that uses the round. The .357 Magnum is a classic revolver rimmed cartridge, and 10mm Auto is designed for use in a semi-automatic pistol, hence its name.
The .357 has a longer case than 10mm, but 10mm Auto has a larger diameter. In other words, the rimless 10mm case is loaded with a 0.40” diameter bullet, whereas the longer .357 Magnum case is topped with a 0.357” diameter bullet, as the name implies.
The 10mm Auto will obviously fire larger, heavier bullets ranging from 135gr to 220gr, with 180 and 200-grain bullets being the most popular. On the other hand, the .357 Magnum is available with bullets ranging from 110gr to 180gr. Most ammo makers produce this round loaded with 125, 158 and 180-grain bullets.
For the marketing cause, Smith & Wesson claimed that the .357 could pierce a car’s door or trunk and driver’s body without a problem. However, it gave birth to a myth that the .357 Mag is so powerful that it can even penetrate an engine block. Of course, it’s nonsense, as very few rifles will go through an engine. Though the .357 S&W Magnum has a longer case and handles the pressure twice that of the .38 Special, it’s just a handgun cartridge.
Nevertheless, since its inception, the .357 S&W Magnum has been considered the “king of the hill.” It was until the fifties that the .44 Remington Magnum cartridge was announced to the public.
The more realistic test is one known as the FBI Protocol, which was introduced in the late 1980s. Firing into ballistic gelatin showed how deep the bullet can penetrate and how it will behave in it. It is determined that the ideal penetration depth is between 12 and 18 inches.
When comparing 10mm vs. .357 in terms of penetration, bullets from both calibers could penetrate between 12 and 18 inches in 10% ordnance gelatin, with several loads rendering severe over-penetration. However, on average, the .357 S&W Magnum loads performed better than 10mm due to their increased muzzle velocity and lighter bullet weight.
In contrast to almost ninety years old .357 S&W Magnum, a 10mm Auto, is a much younger cartridge introduced in 1983. The timing was good, as the 10mm appeared at that time when semi-automatic pistols were widely considered, finally rendering the revolver obsolete.
The law enforcement magnumania didn’t persist in the 80s, as the modern times brought new trends in the police departments searching for more dependable stopping power and greater firepower. The 1980s was definitely a revolutionary time in handgun development. After several less successful attempts with various calibers, law enforcement all over the nation started adopting pistols of that period chambered in 9mm Luger.
While the 9mm Luger was a good combat handgun cartridge with an excellent balance of power and size, it hasn’t had enough foot-pounds energy to eliminate the human-sized threat quickly.
In the quest for the cartridge that would bridge the differences between 9x19mm Parabellum and .45 ACP (11.43x23mm), the 10mm (10x25mm) appeared as a golden mean. Finally, the US Lieutenant Colonel and renowned firearms writer Jeff Cooper developed the 10mm Automatic cartridge with his team and famous Swedish ammo maker Norma AB.
The motive for creating this round was similar but not similar to the .357. The 10mm Auto was purpose-built to give law enforcement personnel more stopping power and provide greater firepower in the fight against well-armed criminals.
The 10mm was initially designed to emulate the terminal performance of the .357 Magnum and offer more power than the 9x19mm Luger and much better ballistics than the heavy and sluggish .45 ACP.
However, depending on loads, it doesn’t always beat out the .357 Magnum in terms of stopping power. Though the 10mm generates a higher energy level than the average .357 ammo, the .357 Magnum with high-performing ammunition is more powerful than the 10mm with commercially available loads.
Similar to .357 derived from a venerable .38 Special, the 10mm Auto was also based on some vintage cartridges. The 10mm was designed using a shortened .30 Remington case to 0.992 inches in length and blown up to accept .40 caliber bullets. The .401-caliber (10.17mm) bullets are borrowed from the nineteenth-century .38-40 Winchester, a revolver cartridge.
Norma’s 10mm initial loading was a 200-grain bullet at 1,200 fps, generating 635 ft-lbs of energy. Since that was too hot for an average shooter, 10mm got a lighter load of 180-grain projectile at about 1,100 fps. The recoil was also slightly lighter than the .357, but the 10 mm recoil energy is almost double that of mainstream 9mm rounds.
As illustrated in the chart, 10mm is available with bullets ranging from 77 to 220 gr, but the most conventional 10mm are 135, 180 and 200-grain bullets.
Modern 10mm Auto ammo offers slightly lower muzzle velocity than .357 Mag, but due to the heavier and larger caliber bullet, the 10mm is a bit more powerful than the .357 Magnum.
The 10mm Auto guns also have a higher capacity than wheelguns chambered in .357. Actually, some models like 15 rounds Glock 20 have 250% more capacity than the standard .357 sixgun. The gun that promoted 10mm was the Bren Ten resembling the popular CZ-75. For the 10mm later were produced colt Delta Elite, Smith & Wesson Model 1076, Glock 20, and the subcompact Glock 29.
Interestingly, while one is a revolver cartridge, and the other is designed for use in semi-auto handguns, you can find pistols chambered in .357 like the Coonan .357 1911 and the .357 Desert Eagle L5 and revolvers in 10mm such as Ruger Super Redhawk.
Although 10mm and .357 cartridges are powerhouses, both rounds are replaced by the more suitable cartridges for law enforcement use. However, they are gaining popularity in civilian market with more firearms manufacturers offering handguns chambered in .357 Mag and 10mm Auto.
The .357 Magnum has smaller diameter but compared to 10mm Auto delivers exceptional penetration. The .357 is also chambered in rifles where longer barrels provide higher velocities and full ballistic potential of .357 making it perfect cartridge for hunting and wood protection.
On the other hand, using the larger bullet diameter and heavier projectiles the 10mm Auto can put threats down quicker and shoot steel silhouette targets with greater authority. If you prefer the wheelguns, then the .357 Mag is the obvious choice. If semi-automatic pistols are your bag, then it’s time to grab a 10mm Auto
With more than 50 years experience in the field and the testing lab, author L.P. Brezny is one of today’s most recognized shotgun experts and authors. He is a contributor to dozens of firearms publications, such as Wildfowl, Shotgun Sports, and Varmint Hunters, and he is a regular columnist in the Gun Digest annual as well as AmmoLand News.