A common caliber mixup among new and seasoned shooters alike is between the .38 S&W vs. .38 Special.  Despite their similar names, the .38 S&W and .38 Special are two different rounds.

Let’s take a look at the .38 S&W vs. .38 Special to clear up the confusion and understand their differences.

.38 S&W vs. .38 Special: What’s the Difference?

Even though both calibers have .38 in their names, the .38 Smith & Wesson (shortened to .38 S&W) and .38 Special are not the same. It doesn’t help that their names are so similar. For example, the .38 Smith & Wesson Special is not the same round as the .38 Smith & Wesson, but instead is another name for the .38 Special. That’s not confusing, right?

Both rounds were designed for use in revolvers and have a rim diameter of .44 inches, but that’s about where their similarities end. The .38 S&W cartridge is shorter and slightly wider than the .38 Special. When comparing the size of the two side-by-side, you’re not likely to mix them up.

The modern .38 S&W boasts a 145 to 146 grain bullet and typically has a muzzle velocity from around 620 to 767 fps. The bullet weight of .38 Special rounds generally range from 110 to 158 grain, with muzzle velocities typically staying around 700 to 1,200 fps.

.38 S&W vs. .38 Special Comparison Chart

	.38 S&W	.38 Special
Parent Case		.38 Long Colt
Names	.38 Smith & Wesson, .38 S&W, .38 S&W Short, 9x20mmR, .38 Colt NP, .38 Colt New Police, .38/200	.38 Special, .38 Sp, .38 S&W Special, .38 Smith & Wesson Special, .38 Spl, .38 Spc, .38 Colt Special, 9x29mmR
Bullet Diameter	.361 inches	.347 inches
Neck Diameter	.3855 inches	.379 inches
Base Diameter	.3865 inches	.379 inches
Rim Diameter	.440 inches	.44 inches
Rim Thickness	.055 inches	.058 inches
Case Length	.775 inches	1.155 inches
Overall Length	1.240 inches	1.550 inches
Max Pressure	14,500 psi	17,500 psi
Velocity	620-767 fps	710-1,175 fps

.38 S&W Background

The .38 S&W is also known as the .38 Smith & Wesson, .38 S&W Short, 9x20mmR, .38 Colt NP (New Police), and .38-200. Smith & Wesson developed the .38 S&W round in 1877 for use in its S&W .38 Single Action revolver. The first version of the round featured a .38 inch heeled bullet. Later versions ditched the heeled bullet design, shrinking the bullet diameter down to .361 inches, while keeping the .38 designation.

The British military used the round from 1922 to 1963. Firearms manufacturer Webley armed the British military with their Mk III revolver, firing a heavy 200 grain bullet. 

Colt, H&R, Hopkins & Allen, Iver Johnson, Ruger, and Smith & Wesson all made revolvers chambered in .38 S&W. Despite its 40 year run as a military round, the round has not had the staying power that other military cartridges have had. Today, you’re not likely to find any new production revolvers in the caliber. So, if you’d like to shoot one, your best bet is finding one used at your local gun shop or at an online gun auction site.

For newly manufactured .38 S&W ammo, you’re limited to very few manufacturers, including Fiocchi, Buffalo Bore, Magtech, and Winchester. That’s why many .38 S&W enthusiasts load their own rounds.

.38 Special Background

Most often when shooters need .38 rounds, they’re looking for the .38 Special. Smith & Wesson developed the .38 Special, also known as the .38 Colt Special, for use in its Military & Police Model revolver in 1902 as a replacement for the .38 Long Colt round.

The .38 Special saw much use by military and law enforcement. United States military members carried .38 Special revolvers in World War I, World War II, the Korean War, and the Vietnam War. It was the standard issued caliber in most US law enforcement agencies from the 1920’s to the 1990’s. 

Today, the .38 Special is arguably the most popular revolver caliber in production. Every major firearm manufacturer that produces revolvers has one chambered in .38 Special. It is also popular as a self defense round, with many shooters choosing concealed carry revolvers chambered in the caliber because of its manageable recoil.

.38 S&W vs. .38 Special: Are they Interchangeable?

The .38 S&W and .38 Special technically are not interchangeable. The .38 S&W is slightly larger in diameter than the .38 Special and therefore should not fit in the cylinder of most .38 Special revolvers. Some people have found exceptions to this rule, specifically with Smith & Wesson revolvers. 

There are cases where a gun chambered in .38 S&W may fire .38 Special ammo.  For example, some World War II era Smith & Wesson Victory revolvers chambered in the British .38/200 S&W have been reamed by importers. Shooters can fit .38 Special rounds into these cylinders and fire them off. The issue, though, is that because of the .38 Special’s higher pressure, the cases will occasionally bulge or split. 

So, while technically the .38 S&W and .38 Special are not interchangeable, there are some exceptions. This comes with the risk of damaging your gun or potential injury to the shooter. The safest bet is to stick with your gun’s designated caliber.

Can you shoot .38 S&W in a .357 Magnum?

As a general rule, you cannot shoot the .38 S&W in a .357 Magnum revolver. The .38 S&W uses a bullet with a diameter of .361”, which is wider than the .357 Magnum’s bullet of .357”. The .38 S&W will likely not fit into the cylinder of the .357 Magnum, but in the case it does, it’s best to proceed with caution. Again, some shooters say it will work, but if you are not willing to risk harming your gun or potentially yourself, it’s best to stick with the gun’s labeled caliber.

Is .38 S&W the same as .38 Special?

The .38 S&W is not the same as the .38 Special. However, the .38 S&W Special is the same as the .38 Special. If your gun is designated as a .38 Special, you should shop for .38 Special ammo for sale instead of .38 S&W ammo.