38 Special vs. 9mm: How the Old Law Enforcement Handgun Cartridge Stacks Up Against the New One

They are two of the most famous and popular cartridges for personal defense and law enforcement, one in the wheelgun world and one in the semi-auto world. They are often compared because they both became popular for the same reasons, which is why the .38 Special vs 9mm argument will be valid as long as both are carried for defense. 

While law enforcement in the U.S. has almost entirely switched over to 9mm, for many decades, the go-to cartridge for those who also carried a badge was the versatile and controllable low-velocity .38 Special in a sturdy six-gun. But times change. 

Today, the 9mm and .38 Special exist in tandem, pulling different duties. While some consider the .38 to be antiquated, both are still valued by many shooters for their capabilities as self-defense rounds. In some ways, with modern bullet technology, both are better than ever. Here’s how they stack up.

.38 Special vs. 9mm Specs

.38 Special

• Introduced: 1898
• Designer: Smith & Wesson
• Parent Case: .38 Long Colt
• Case Type: rimmed, straight
• Bullet Diameter: 9.1mm / .357 inches
• Case Length: 29.3mm / 1.155 inches
• Overall Length: 39.4mm / 1.55 inches
• Max Pressure (SAAMI): 17,500 psi
• Bullet Mass: 8.1 grams (125 grain) – 10.24 grams (158 grain) 
• Velocity: 755 fps – 1,150 fps

9x19mm Parabellum

• Introduced: 1902
• Designer: Georg Luger
• Parent Case: 7.65x21mm Parabellum
• Case Type: rimless, straight
• Bullet Diameter: 9.01mm / 0.355 inches 
• Case Length: 19.15mm / 0.754 inches
• Overall Length: 29.69mm / 1.169 inches
• Max Pressure (SAAMI): 35,000 psi
• Bullet Mass: 7.45 grams (115 grain) – 8.04 grams (124 grain)
• Velocity: 1,180 fps – 1,345 fps 

.38 Special vs 9mm History

.38 Special History

People tend to think of the .38 Special as the older of the two cartridges, and that’s true, but only by four years. 

A Black Powder Cartridge

The .38 Special hit the gun world in 1898, on the cusp of a new century and a new modern age of firearms. The rimmed, centerfire, straight-walled cartridge designed by Smith & Wesson went on to become the standard service cartridge for the majority of American police departments from the 1920s through the 1990s. It also saw duty on the frontlines of World War I, World War II, the Korean War, and in the jungles of Vietnam.

The .38 Special was created as an improvement to the underwhelming .38 Long Colt, which famously displayed a lack of adequate stopping power in the Philippine-American War. 

It was designed from the start by S&W to be a high-velocity revolver round (for the time) that would solve the penetration problems of the .38 LC by increasing speed instead of bullet mass. Essentially, it was the opposite approach taken by John Browning with the .45 ACP. 

Believe it or not, the original .38 Special was introduced as a black powder cartridge and it was designed for the lower pressures of that propellant. But within a year, its popularity pushed S&W to switch it to a modern smokeless powder load. The round went on to be revered for its accuracy at defensive distances and its manageable recoil, even in small revolvers. 

The “.38” in the name refers to the rough diameter of the brass case when loaded, not the bullet diameter, which is 0.357 inches. 

The original .38 Special held a greater charge than its predecessor and pushed a 158-grain bullet about 150 fps faster than the .38 LC. In the 1920s, as police began to battle bootleggers and the organized crime that was spawned by Prohibition, a law-enforcement version of the cartridge was made by Western Cartridge dubbed the .38 Super Police, though its heavy bullets tended to tumble and it wasn’t popular. Still, law enforcement had been turned on to the .38 Special.

Prohibition Era and Adoption by Law Enforcement

In 1930, S&W released its first large-frame revolver chambered in .38 Special with a 5-inch barrel and fixed sights. It was clearly intended to be a duty gun and the Smith & Wesson 38/44 Heavy Duty was used as such. About a year later, the .38/44 Outdoorsman was released with a 6.5-inch barrel and adjustable sights. 

To go with the beefy new wheel gun, a juiced up round topped with 158-grain metal-tipped bullet was soon introduced, and law enforcement who were looking for a round that could penetrate automobiles and body armor of the day, well, they dug it. 

Gun makers started designing their .38 revolvers, like the classic Colt Official Police revolver, to be tougher in order to handle higher pressures and thus began the quest to load the .38 Special hotter and hotter. This eventually led S&W to develop the legendary .357 Magnum, which hit store shelves in 1935.    

It was around then that the length measurements of this family of cartridges presented some safety concerns, which shooters should still be aware of. While the diameters of the .38 Short Colt, .38 Special, and .357 Magnum are identical, they differ in length, but only slightly — just enough to not be backward compatible.   

You can shoot .38 SC in a .38 Special Revolver, for example, and you can shoot both in a .357, but the .357 Magnum is too high pressure for guns chambered for the shorter cartridges. Usually they won’t fit, but don’t try it, and if you have anything that even remotely resembles a vintage firearm, double check the chambering and never use +P loads or magnum loads in guns that weren’t made for them.  

WWII and Beyond

After the U.S. joined World War II, some aircrews were issued S&W Victory revolvers, which were simply Model 10 M&P revolvers repurposed for the war effort. During WWII, nearly 600,000 of these revolvers were sent to the United Kingdom, Canada, Australia, New Zealand, and South Africa under the Lend-Lease program, mostly chambered in the similar British .38/200.

For their .38s, the Americans used a new steel-jacketed, copper flash-coated bullet developed by Springfield Armory that met the conditions of the Hague Convention. It pushed a 158-grain bullet about 850 fps from a 4-inch barrel.  

In the 1950s, the Air Force adopted the M41 ball cartridge — a .38 Special with a 130-grain full metal jacket bullet moving at 725 fps. It was a light load meant to prolong the life of the Air Force’s S&W M12 revolvers that had aluminum cylinders and frames. By the 1960s, a hotter version of the M41 was issued with the same 130-grain bullet moving at 950 fps from a 6-inch Army revolver. 

These revolvers usually served as sidearms for personnel in support roles who weren’t carrying an M1911.  

In the 1970s, the Federal Bureau of Investigation was still carrying .38 Specials, and in 1971 the agency introduced a new .38 Special +P round that they called the “FBI Load.” It was topped with a 158-grain non-jacketed soft lead semi-wadcutter hollow point bullet designed to expand at regular .38 Special velocities. The load proved effective, and was subsequently adopted by several major police departments.

But the workhorse .38 wasn’t done. Eventually, Federal and Winchester introduced the first .38 Special +P+ loads intended for specially designed .38 revolvers and for .357 Magnum revolvers with a velocity of about 1,100 fps. Some loads have pushed the cartridge even faster.

However, the hurdle the .38 Special couldn’t overcome, in the end, was the limited capacity of a wheelgun. 

9x19mm History

The 9mm cartridge was released four years after the .38 with very different origins and a very different path to becoming the preferred U.S. law enforcement round. 

From Austria With Love

The rimless, tapered 9x19mm Parabellum was created by Austrian firearm designer Georg Luger in 1901 as a more powerful overall handgun cartridge for a specific, early semi-auto pistol: the Luger. That’s why the cartridge has the alternate name of “9mm Luger.” The German military wanted a handgun round with more juice, and Luger answered the call.

The original Luger pistol, patented in 1908, was a refined version of the Borchardt C-93 pistol, chambered for the 7.65x21mm Parabellum — the 9mm’s parent cartridge. The “parabellum” is derived from the latin motto used by the long defunct German arms company Deutsche Waffen-und Munitionsfabriken (DWM): “Si vis pacem, para bellum” (if you want peace, prepare for war.).

The Luger pistol chambered in 9mm became the German P08, a legend of WWI and WWII battlefields. The gun and cartridge were presented to the British Small Arms Committee and three prototypes were sent to the U.S. Army for testing at the Springfield Arsenal in 1903.

It was readily adopted by the German army and navy and the 9mm became the standard German pistol cartridge through both world wars. The round was lightweight, fast, and was more effective on target than revolver rounds of the day thanks to that high velocity. And the high pressures the 9mm generated promoted reliable cycling in semi-autos. 

The 9mm in World War II

The Luger P08 was produced until 1943 and issued through 1945 . It had a great reputation for accuracy and reliability (though the action could be a bit finicky in battlefield conditions), but its complex design was slow and expensive to manufacture.

The P08 was replaced by the cheaper and simpler Walther P38 before the end of the war, also chambered in 9mm, which was the first locked-breech DA/SA pistol. If you ever have the chance to handle one, you’ll notice a number of similarities to the later Beretta 92 series of 9mm handguns.

But let’s take a step back. In 1935, a design for a high-capacity semi-auto 9mm handgun begun by the legendary John Moses Browning was completed by gun designers at FN Herstal in Belgium who produced the first Browning “High Power” pistol. The name referred to the impressive capacity of the pistol’s double-stack magazine: 13 rounds; more than double the capacity of revolvers of the day and the 9mm Walther P38.

During the war, when Belgium was occupied by Nazi Germany, the FN factory was used by the Wehrmacht to build the Hi-Power as the “9mm Pistole 640(b),” since the Germans already had ammo for it. 

Meanwhile, FN Herstal continued to build the pistol for Allied forces on the other side of the Atlantic in Canada at the John Inglis and Company plant. And so, the 9mm became one of the very few cartridges used by both the Allied and Axis forces during the war. 

After the war, the 9mm cartridge was later adopted as the standard pistol and submachine gun cartridge of NATO and many independent nations. Thanks to the high magazine capacity offered by 9mm handguns, as the decades passed and the ammo got better, more and more law enforcement agencies took note, and so did the U.S. military. 

The Army ditched the aging M1911 in .45 ACP for the 9mm Beretta M9 in 1985. This 9mm pistol went on to replace the 1911 in every branch of the military. A number of large and small police departments switched from their .38 Special revolvers to 9mm semi-autos in the 1980s and 1990s until the 9mm became the dominant cartridge for law enforcement in the U.S. 

The FBI Adopts the 9mm

After the infamous “FBI Miami shootout” in 1986, the Bureau began to reevaluate the wisdom of carrying revolvers as primary service weapons in the modern age. Eventually, the agency switched semi-autos. Though it took a good number of years (more on that in a bit), the Bureau finally settled on the 9mm. 

When the FBI began to ask questions, so did other agencies. In the late 1980s, the LAPD began the switch to 9mm Beretta 92 series pistols in 1986, while the NYPD soon switched to 9mm SIG Sauer pistols and then Glocks. Nearly all law enforcement agencies followed suit in the following years. 

These modern 9mm semi-autos were more powerful than a .38 Special, far easier to control for the average shooter than a .357 Magnum, and offered, even in the smallest service pistols, at least double a revolver’s capacity. Plus, they came with the faster reload speed and higher overall carry capacity of magazines. 

Something else happened in the 1980s that was pretty important for the 9mm: the introduction of the first Glocks. The Glock 17 came out of Austria — the birthplace of the 9mm — in 1982, followed by the Glock 19 in 1988. 

The handguns set a new standard for pistols for decades to come, especially duty pistols for law enforcement,  and they were both chambered in 9mm only. This helped cement the cartridge as the new self-defense and law enforcement round heading into the 21st century. 

Performance

Cartridge	Bullet Weight (grains)	Muzzle Velocity (fps)	Muzzle Energy (ft. lbs.)	Max Pressure (SAAMI)
.38 Long Colt	150	777	201	12,000
.38 S&W	145	650	136	14,500
.38 S&W Special	158	940	310	17,000
.38 Special +P	158	910	351	18,500
.38 Special +P+	110	1,100	295	22,000
.380 ACP	100	895	178	21,500
9mm	115	1,300	420	35,000
.357 Magnum	158	1,350	639	35,000
.357 SIG	125	1,450	585	40,000

.38 Special Performance

Considering it was developed for black powder, it’s no surprise the .38 Special is inherently a low-pressure round. In fact, it has one of the lowest chamber pressures you can find today. 

In the .38 Special you have a 126-year-old cartridge that fires medium-sized bullets slowly. But the game changes a bit when you get into the previously mentioned +P and +P+ loads, which have chamber pressures of around 20,000 psi and produce about 20 percent more muzzle energy than regular .38 loads. 

But the performance still isn’t remarkable — you end up with a round that shoots somewhere between a .380 ACP and a 9mm. Of course, the longer the barrel, the better the performance. High-pressure .38 Specials can perform pretty well from a carbine barrel, which is cool if you have a lever gun chambered for .357 Magnum. 

So, why is the .38 Special still around? Because it’s controllable. 

High pressure or high velocity rounds are a handful in a short-barreled handgun. Anyone who has ever fired a snubby .44 Magnum, or something larger, knows that the lighter the gun and shorter the barrel, the more punishing it can be on the wrists, and the slower follow-up shots are. 

A .38 Special in a tiny, featherweight aluminum-framed revolver with a 1-inch barrel like an S&W J-frame, is still manageable for most shooters and surprisingly accurate. And snubby revolvers still have their place as primary easily-concealable CCW firearms and as backup guns for those who feel they need them. 

Read Next: Best Revolvers

9mm Performance

Handgun shooters have adopted the 9mm in droves for two reasons, magazine capacity and moderate recoil. Some people describe the recoil of very compact 9mm pistols as snappy, usually meaning there is a lot of muzzle flip, which can be an issue for really small guns and small shooters. But in a full-size pistol, the recoil of a 9mm is extremely manageable for the majority of shooters. 

There was a time when the 9mm was called underpowered by some — usually folks who carried .45s. Then came the introduction of the .40 S&W and critics said it would be the end of the 9mm. Law enforcement agencies all over the country adopted the new cartridge, which was sold on being more powerful than a 9mm, which “could bounce off a windshield” while not taking up as much magazine space as a .45. 

In reality, .40 S&W pistols did have a decreased mag capacity compared to their 9mm counterparts and the round generated higher pressures than a 9mm, meaning it had more recoil and it was rough on guns. Plus, 9mm ammo technology advanced so quickly, soon the .40 S&W’s ballistic advantages were overshadowed by +P 9mm loads topped with modern bullets. 

After flip-flopping around from the 9mm to the 10mm to the .40 S&W and then back to the 9mm, the FBI released a report in 2014 saying that when comparing 9mm, .40 S&W, and .45 ACP cartridges developed for the agency, the new propellants and bullet design used by modern 9mm defensive loads were comparable to the other two larger rounds while also delivering less recoil, greater mag capacity, and less wear on firearms.  

After a brief dalliance with the .40 S&W, many U.S. law enforcement agencies now use 9mm handguns — as many as 60 percent, according to Newsweek.

Read Next: Best 9mm Ammo

Final Thoughts on the .38 Special vs 9mm

Comparing the .38 Special vs 9mm is only interesting from the perspective of the history of law enforcement sidearms. At this point, there are so many great options for self-defense concealed-carry semi-auto handguns in 9mm that are designed to mitigate the extra recoil and muzzle flip from the speedy round that the only real reason to go with a .38, even a +P load with a modern self-defense bullet, is because a person really, really likes carrying a revolver and they don’t want the recoil of a .357 Magnum.

There’s still a place for that ultra-compact profile of a 5-round wheelgun in .38. However if you size up to a larger revolver, the check marks in the pro column for the .38 are few. 

That doesn’t mean the .38 doesn’t have its home in the modern self-defense landscape. It clearly does, and plenty of people still prefer to carry a compact revolver.

That said, when it comes to capability and versatility, the .38 can’t hold a candle to the ubiquitous and endlessly popular 9mm, which has come to represent the right balance of capacity, velocity, power, and accuracy for most handgun shooters for most applications.