The 10mm Auto: From TV Fame to Real-Life Adoption

The 10mm Auto is widely favored in the shooting community. Since its emergence in the 1980s, the weapon swiftly gained recognition among gun enthusiasts, partly because of its utilization on the TV display ‘Miami Vice .’Nevertheless, its fame was slightly reduced in the early 1990s for various justifications. Nevertheless, the 10mm Automatic is regaining fame again, particularly with those desiring a potent semi-automatic handgun for hunting and self-preservation.

This post will briefly summarize the 10mm Automatic cartridge, including its history, performance features, and ideal applications.

10mm Auto Background

In 1983, Norma AB worked with Whit Collins, John Adams, Irving Stone, and Jeff Cooper, a well-known firearms author and instructor, to create the 10mm Automatic cartridge. They used.30 Remington cases and loaded.38-40 Winchester.40 caliber bullets into them. The goal was to create a bigger and better gun than the 9mm Luger and the .45 ACP.

They were very close to achieving that goal. The original 10mm Auto ammo shot a 200-grain bullet at 1,200 feet per second, which was significantly faster and had more muzzle energy than the 9mm Luger and .45 ACP. Dornaus & Dixon Enterprises collaborated with Jeff Cooper and the 10mm Auto team to develop a handgun to fire the new cartridge: the Bren Ten pistol.

The Bren Ten, which looks similar to the CZ-75, became famous partly due to Sonny Crockett in the television show Miami Vice. 

Because of this, the number of people wanting to buy the pistol and the cartridge increased greatly in the middle of the 1980s. 

The Bren Ten was introduced too quickly and had reliability and quality control issues, which gave the pistol a bad reputation. There was also a shortage of magazines. After making some early mistakes, the company could not improve its situation and went bankrupt in 1986.

Dornaus & Dixon and the Bren Ten nearly caused the 10mm Auto to fail. Some designers at Colt were interested in the 10mm Automatic. Colt released a Model 1911 modified to fire the Delta Elite cartridge not long after the Bren Ten were killed.

Around this time, the 10mm Auto gained the interest of the FBI during their search for a more powerful service round. This happened following the disastrous shootout with two bank robbers in Miami in 1986.

The FBI was impressed with the cartridge’s performance during their evaluation. It was briefly used in the Smith & Wesson Model 1076 handgun. However, the bureau ultimately decided that the full-power 10mm load produced more recoil than most agents could handle. Indeed, the FBI test report on the cartridge was labeled:

Use extreme caution when handling velocities, pressures, and recoil, as they can cause damage to weapons with extended use. 

Control for multiple shots is extremely difficult.

This led the FBI to adopt a reduced power 10mm Autoloader. The 10mm FBI or 10mm Lite load was several hundred feet per second slower than the original 10mm Auto. 

However, the FBI was still satisfied with its penetration and terminal performance. Smith & Wesson later discovered that it could achieve the same performance specifications by shortening the 10mm case by several millimeters, so the 10mm case would fit into a medium-frame handgun.

After testing different types of ammunition, Smith & Wesson decided to create a new cartridge. The new cartridge was named the .40 Smith & Wesson but is also known as the .40 S&W. While the .40 S&W was relatively popular among law enforcement agencies and ended up supplanting the 10mm Auto in most cases, fans of the 10mm Auto still scornfully refer to the .40 S&W as the .40 Short and Weak.

Most law enforcement departments have yet to adopt the 10mm Auto cartridge. Still, it has recently experienced a surge in popularity with hunters. At present, the .223 Remington round is welcomed by many hunters across the US who utilize it to protect themselves from both two-legged and four-legged perils. Due to its increasing renown, major ammunition producers now fabricate pre-loaded 10mm Auto ammo. Multiple varieties, such as Barnes, Buffalo Bore, Corbon, Double Tap, Federal, Hornady, Remington, Sig Sauer, Speer, Underwood, and Winchester, are available.

Of the bullets typically used for hunting, the 180 and 200-grain bullets are the most popular. Also available are bullets with weights of 135gr, 150gr, 155gr, 165gr, 175gr, 190gr, and 220gr.

The performance of each 10mm Auto load will differ depending on the barrel length of the gun it is fired from. However, many manufacturers produce 10mm Auto ammunition closer to 10mm FBI specifications than the original 10mm load of a 200gr bullet at 1,200fps.

An example would be Hornady’s advertising of a muzzle velocity of 1,275fps for their 10mm 180gr XTP bullets. This cartridge has an average amount of kinetic energy at the muzzle, with 650 ft-lbs.

However, plenty of hotter loads exist for the 10mm Auto. Buffalo Bore offers two types of 10mm ammunition- one with a 180-grain jacketed hollow point bullet that travels at 1,350fps and another with a 220-grain hard cast bullet that travels at 1,200fps. Double Tap offers a 135-grain load that fires at 1,600fps, as well as a 180-grain load that has a velocity of 1,300fps.

All 10mm Auto loads have a relatively flat trajectory compared to most other handgun cartridges. Accuracy is just one of the many great qualities of the.223 Remington cartridge.  

A talented marksman should be able to hit targets consistently at 100 yards or more.

The 10mm Auto has more recoil than other guns, but experienced shooters can still handle it. This statement is particularly true when measuring the success rate of long slide 10mm Auto handguns currently in production.

Although the Bren Ten ceased production a few years after its creation, Glock revived the cartridge when they introduced the Glock 20 in 1991. Since the original company started, other companies have started making handguns that fire 10mm bullets. Many 10mm Auto pistols are available for hunters and shooters, including the Glock 20, Sig P220, Dan Wesson Razorback, EAA Witness, Nighthawk Long Slide, Ultra FS HC by Rock Island Armory, Wilson Combat CQB, and Kimber Super Eclipse.

Colt began making the Delta Elite again in 2009 and continues to make a small number of them each year.

All About 10mm Auto Ammos

The 10mm Auto handgun cartridge has a straight wall and no rim for full-size service pistols. It is a potent round with a high muzzle energy that works well for hunting and self-defense. The case length is 25.2mm, and the bullet has a 10.17mm diameter.

The case of the 9mm Luger is 19.15mm long, while the case of the.45 ACP is 22.8mm long. According to SAAMI, the.357 Magnum cartridge’s case is shorter than its overall length.

Although lighter-than-caliber and heavier loads are also available for a range of applications, the most popular bullet weights for this caliber are 175 grains, 180 grains, and 200 grains.

What are the 10 mm origins?

The 10mm Auto cartridge was created in the 1970s by Col. Jeff Cooper, Michael Dixon, and Thomas Dornaus for a brand-new semi-automatic pistol based on the CZ 75 concept. The.45-caliber M1911A1 was intended to be replaced by a more potent cartridge with a higher trajectory and could hold more rounds.

This new handgun would go on to become known as the Bren Ten. Built on earlier experiments, the 10mm Auto was a potent round. Cooper’s own 40 G&A (Guns & Ammo). 40 Great idea.

Miami Vice

miami vice

In the 1980s, the 10mm Bren Ten gained popularity due to the TV series Miami Vice. Sonny Crockett, played by Don Johnson, used a Bren Ten as his main gun, which he kept in a Galco leather shoulder holster. 

Though sales were not impressive, the company expected they would be enough to keep them in operation. Unhappily, this wasn’t the situation, and Dornaus & Dixon declared bankruptcy in 1986 after selling merely 1,500 guns.

Still, this didn’t terminate the 10mm pistol’s voyage. In a similar year where the initial FBI agent was terminated, two other agents died in the Miami fight, and five were wounded. 

Following this gun disagreement, the FBI appraised its procedures and tools to decide what could be enhanced, counting the types of arms and cartridges utilized. The FBI is now searching for a fresh law enforcement caliber and checked the 9mm and .45 ACP calibers.

Commercially available 10mm ammunition is still hotter than the original FBI load. The FBI found that the 10mm Auto loads available for purchase were too powerful for recruits in 1988. This ammunition is still much stronger than the original FBI load. The manufacturers developed the .40 S&W to have less recoil and more control over the sidearm. The .40 S&W is a lower-pressure version of the 10mm, with a shorter case.

Many 10mm Auto loads today are not as powerful as they used to be, providing shooters with a more practical balance between energy and control.

Capacity and Feeding

The issue of capacity is open to discussion. A pistol with a higher ammunition capability allows the shooter to make precise shots and necessitates fewer recharges. Some sharpshooters reason that a handgun used for concealed carrying must have a minimum capacity for self-defense to be effective.

You need to assess the risk level and select a reliable firearm that you can shoot accurately.

10mm capacity

This indicates that pistols with either a single-column or double-column magazine can fire the 10mm Auto cartridge. For those who prefer a lot of ammunition, the 10mm caliber is preferable.

15 rounds fit in a standard Glock 20 magazine. The G29 and other subcompact weapons can hold 10+1 rounds. Typically, a 10mm revolver holds six rounds.

Revolvers that fire the.357 Magnum, and those that fire other cartridges typically have the same capacity. However, some revolvers that fire the.357 Magnum has as many as eight chambers. A semi-automatic pistol that fires 10mm rounds has nearly twice as many rounds per magazine as a handgun that fires.357 Magnum rounds of a comparable caliber.


Functionality and dependability are the most crucial requirements for a self-defense firearm. As long as you are using fresh ammunition from a factory in good condition, the reliability of your weapon typically depends more on the weapon itself than the caliber of ammunition you are using. Rimfire ammunition stands out as an exception.

The dependability of a 10mm revolver is no different from that of any other revolver that fires.357 Magnum rounds. The procedure for reloading will be different. You will typically need to use half- or full-moon clips to extract used cartridges because of the 10mm Auto headspaces on the case mouth. You not using or being unfamiliar with these clips could be a problem.

The Best 10mm Ammunitions

The best 10mm load for self-defense is the Barnes VOR-TX 155-grain SCHP. According to Lucky Gunner’s testing, this bullet’s diameter doubled between.40 and.81 calibers.

This statement that the penetration is 12.3 inches is good news because it satisfies the FBI’s minimum requirement. For those concerned that their bullets won’t hit their target, this load offers a compromise because it has the right amount of power to be efficient without overpowering.

In addition to offering consistent results, the Barnes VOR-TX gives the shooter more control over the recoil. The muzzle velocity and energy of a 155-grain bullet fired from a Glock 20 with a 4.6-inch barrel are 1,073 ft/s and 396 ft-lbs, respectively. Although it falls short of the advertised 1,150 ft/s and 455 ft-lbs, it is still efficient.

Captain Hunter is a seasoned hunting mentor with over 20 years of experience in the field. His passion began as a young man on trips with his father and grandfather in the Colorado mountains. Today, he shares his unmatched skills in survival, tracking, and marksmanship through his website When he's not volunteering with youth hunting programs, you can find Captain Hunter providing expert hunting tips, gear reviews, and answers to your most pressing questions. His decades of experience make him the trusted guide to help any outdoorsman master the sport.

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