What’s The Difference Between Caliber and mm? (9mm Vs. 380 Caliber)

 

The 380 and 9mm are two of the most popular ammunition. The two have the same bullet diameter. But are they alike? Better yet, are they interchangeable?

This post analyzes the two cartridges side by side to help you determine which one works best for your needs.

Let’s get cracking.

We’ll start with the basics.

9mm vs. 380 Caliber — A Brief History

The 380 ACP first graced the market in 1908. It was designed by John Browning and introduced by Colt as a self-defense caliber.

Side Note: ACP is an acronym for automatic colt pistol.

The 380 featured a weak bolt thrust for the classic blowback pistol, which didn’t have barrel locking.

The 9mm, on the other hand, was designed by George Luger. He first introduced it to the British Small Arms Committee in 1902. The following year, Luger handed over three prototypes to the United States Navy.

The German Navy adopted this caliber in 1905, while their army counterpart started using it in 1906.

The first 9mm had a lead score and was designed for military use. Later, during WWII, it adopted a core jacket before going to the standard copper core in 1944.

380 vs. 9mm — Usage

Some foreign police forces use 380 as their caliber of choice. The US police and a host of other military forces use it for backup purposes.

The 380 doesn’t have the same power level as other similar-sized pistols like the 38 Special or the 9mm. Still, the 380 is largely used for self-defense among civilians. It’s relatively small, making it easy to conceal from the public eye. Besides, it can hold a relatively high number of rounds.

The 9mm Luger is popular with US law enforcement agencies. The reason behind this is the availability of small guns with a large magazine round capacity compatible with this caliber. It is also a common self-defense caliber with civilians in states where it is allowed.

380 vs. 9mm — Recoil

The recoil has more recoil energy than the 380 ACP. Because the 380 has a gentler recoil, you can control multiple shots better at close range.

 

The 9mm is accurate at longer distances despite the powerful recoil energy. Besides, the 9mm is heavier, which enables it to offset most of the recoil.

If you fire from a 380 ACP handgun weighing the same as a 9mm handgun, the 380 will deliver significantly less recoil. Firing a 380 pistol generates up to 90% less recoil than shooting from a 9mm handgun despite the guns weighing the same. This allows you to take more accurate multiple-shot placement downrange.

Remember, your strength mat determines which handgun you should purchase. The stronger you are, the better control you have over the recoil.

380 vs. 9mm — Ballistics

Ballistic tests show that the 9mm Luger is superior to the 380 ACP. Because the 9mm sports an extra 2 mm case length, the 9mm is the bigger cartridge. As a result, it boasts more muzzle velocity and muzzle energy. On top of that, it can penetrate deeper than 380 ACP.

380 vs. 9mm — Stopping Power

According to the FBI, penetration is the best parameter when judging a bullet’s ability to stop an attacker in self-defense shootings.

Based on the load and bullet mass, the 9mm penetration ranges between 8 and 24.5 inches. The 380 ACP’s penetration, on the other hand, is between 6.5 and 17 inches.

Leveraging the FBI analysis, a caliber that offers 12+ inches of penetration can help keep aggressors at bay.

Since both 380 and 9mm can deliver a penetration power of more than 12 inches, you shouldn’t have a problem protecting yourself in self-defense shootings.

380 vs. 9mm — Ammo and Handgun Cost

The 380 ACP cartridges are relatively more expensive than their 9mm counterparts. The reason for this is the high supply of the 9mm caliber. Plus, 380 ACP enjoys a higher demand than the 9mm.

You can get a 9mm ammo for about $0.55 and a 380 round for $0.85.

The trend is the same for self-defense. An HST hollow point in Federal 9mm goes for about $1 a round, while a 380 Auto JHP ammo sells for $2.

The trend is an indication of the 9mm Luger’s popularity. Of course, you can save money by buying in bulk.

Regarding handgun costs, 380 weapons are cheaper than their 9mm counterparts. You can get a solid 380 pistol for less than $200. 9mm weapons sell for $300 or more.

380 vs. 9mm — Concealed Carry

The 380 is comfortable for concealed carry. A 380 Auto subcompact handgun is a small gun and easy to conceal.

Conversely, a 9mm handgun is a bigger gun since it uses a more powerful cartridge, requiring more material to construct the frame and slide rigidity.

Weight matters when it comes to concealed carry.

A larger gun like the Glock 17 is harder to conceal than the compact Ruger LCP.

380 vs. 9mm — Performance

The 380 ACP gun power is lower than that of 9mm weapons.

The 380 delivers a maximum velocity of 1,000 FPS and an energy rating of 149 Mpa. Even though this means less destruction, the cartridge performs with less recoil, making it ideal for short-range shots.

The 9mm delivers a high velocity of 1,400 FPS and an energy rating of 2,465-foot pounds. This means a stronger recoil, which lowers the accuracy in rapid-fire situations.  

380 vs. 9mm — Reloading

The 380 ACP and the 9mm are straight-walled pistol cartridges. They are, therefore, easy to reload.

Plus, you tinker and determine your ideal practice ammo for the 9mm cartridge because there are enough gun power bullet weights to select from.

And since the 9mm and the 380 brass have the same rim diameter, you should be careful not to load the wrong cartridge in the wrong gun accidentally.

These aren’t the only differences between these two cartridges. See the table below to discover more details.

 

The Bottom Line: 380 vs. 9mm — Which is the Right One for You?

The 9mm and 380 are good cartridges for self-defense and concealed carry.

From a ballistic view, the 9mm stands out with high muzzle energy and velocity but lacks an increased coil.

Further, the 380 ACP offers 50% less recoil, making it ideal for everyday carry because 380 handguns are slim and lightweight than their 9mm handguns.

Even though both cartridges cannot match the stopping power of 44 Magnum and 45 ACP, they’re excellent for self-defense.

So, which caliber is good for you?

If you’re recoil sensitive or think a 9mm subcompact is snappy for your needs, the 380 ACP could be the best choice for you.

But don’t mind the higher recoil of the 9mm; it could be a good option.

Remember, shot placement is essential; choose a caliber that’s comfortable to use with your weapon.