10mm Pistols: Complete Guide to 10mm Handguns

10mm Handguns - History and Success

The 10mm pistol is a high powered weapon with the backing of a niche community that appreciates raw strength and the protection of pure power.

Those who carry the weapon appreciate it for the abilities it brings to the table for hunters and law enforcement alike.

Its development and percolation into the firearms community has passed through the famed hands of Jeff Cooper, researched by the ranks of the FBI and further developed in the wake of a 1986 shootout still studied by the law enforcement officials throughout the nation.

Invention of the 10mm Handgun

Arguably, not many names spark as much respect in the shooting industry as Colonel John Dean "Jeff" Cooper's, and his contribution to the development of the 10mm handgun lends credence to the caliber that does all the right things for a niche group.

According to a piece in Guns & Ammo -- which interestingly as an entity played a role later in the development of the 10mm -- Cooper was born in 1920 and served in both World War II and Korea. He retired as a lieutenant colonel.

He was a high school and college teacher before he opened the American Pistol Institute and later influenced how responsible shooters utilized their weapons. Cooper advocated for the defensive mindset and developed the four rules of gun safety.

According to Bren Ten, which developed the popular 1980s 10mm weapon that was toted by pop culture icon Detective Sonny Crocket in Miami Vice, someone named Whit Collins in the early 1970s researched the feasibility of rechambering the 9mm Browning Hi-Power to a stronger cartridge.

His initial intent was to further develop the .38 super, but Cooper suggested instead a 200 grain bullet at a .400" diameter at a velocity of 1,000 feet per second. Collins researched feeding geometry to determine whether or not the .40 caliber bullet was a possibility and later approached Cooper.

With Guns & Ammo lending research and Cooper supporting the endeavor, the idea was taken to Irv Stone of Bar-Sto and master gunsmith John French, according to Bren Ten. By 1972, the team was test firing a Browning Hi-Power chambered in .40 G&A, at 180 grains fired at 1,050 fps from a 5 inch barrel.

Collins and Cooper later split ways -- with Collins developing the .40 G&A and Cooper focusing on the .40 Super. Later Cooper teamed with Thomas Dornaus and Michael Dixon to create what became the 10mm auto -- at 10.16 mm with a jacketed truncated cone (JTC) at 200 grains fired at 1,200 fps.

Its popularity was later spread due to the FBI briefly designating it their standard issue caliber.

10mm Pistol Adoption by the FBI

On April 11, 1986, FBI special agents engaged two armed criminal bank and car robbers, and it was after the dust settled from the conflict that the FBI chose to pursue firepower that would penetrate deeper and more efficiently dispatch lethal targets -- though it took some effort to decide on the 10mm caliber.

William R. Matix and Michael Lee Platt, the criminals apprehended by FBI SAs, seemed to be normal guys, despite hidden dark sides, who met in the military and later reconvened in Miami, Florida in the wake of personal loss.

According to the FBI report following the 1986 FBI Miami shootout, Matix grew up with a stutter in Ohio, later needing professional treatment to terminate the speech impediment. It was at the Walter Reed Army Hospital during speech therapy that he met his soon-to-be first wife, Patricia "Patty" Buckanich.

Matix, who was later a military policeman, and his wife spent time traveling between various locations before settling in Columbus, Ohio, where Patty was later murdered with a colleague on December 30, 1983. Additionally, on the day Patty was murdered at Riverside Methodist Hospital Research Foundation William Matix's father, Russell Matix, suffered a stroke.

Terminal cancer soon wrought the life from Russell, who later passed in April 1984. Over this period, William declared himself a born-again Christian and spoke often during religious ceremonies, speaking about how he overcame the stigma of Patty's murder.

All the while, he received a life insurance settlement of approximately $180,000. However, the amount was far less than he had anticipated and he became "bitter," according to the FBI report released under the Freedom of Information Act.

The other criminal shooter and robber, Platt, was the son of a U.S. Navy Petty Officer, and was therefore subject to several relocations in his youth -- San Diego to Pearl Harbor to Alameda to Yuma, Arizona, where Platt graduated from high school in 1972.

Enlisting in the military after a history of high school sports, Platt was assigned to a Military Police Unit at Fort Campbell, Kentucky, following completion of Paratrooper Air Assault School. It was in that unit that Platt and Matix met and served together.

Furthermore, according to a 1986 report from the New York Times, Regina Platt, Michael Platt's wife, committed suicide in December 1984.

This was two months after the end of an affair Michael had with a local waitress, according to the FBI report.

Regina, Michael and William Matix worked together at a business called Blade Cutters.

Though their wives' deaths were seemingly coincidental, the deaths may have been a contributing factor (though this is a purely speculative statement) as to why Matix and Platt later began a series of violent robberies over the span of 1985 and 1986.

When FBI agents attempted to apprehend these armed, dangerous criminals they had been tracking, Matix and Platt opened fire, killing two SAs and wounding five. The firefight was marred by glaring sunlight and clouds of dust from a preceding speed pursuit, further inhibiting the FBI from executing the lethal threats.

Part of the issue during the mass shootout -- heroically finished through the efforts of FBI special agents Gordon McNeill, Richard Manauzzi, Benjamin Grogan, Jerry Dove, Edmundo Mireles, Jr., John Hanlon, Gilbert Orrantia and Ronald Risner -- was that the officers' weapons did not adequately penetrate the perpetrators.

They used 9mm pistols, 12 gauge Remington shotguns (though only one was actually fired) and Smith & Wesson revolvers. Autopsy reports show Matix and Platt had a total of 18 gunshot wounds, with multiple in kill zones, before they were finally dispatched.

Something needed to change, and the FBI focused on the firepower.

The 10mm Handgun Was Eventually Replaced by the FBI

The penetration of the standard issue .38 caliber was deemed unfit and the FBI adopted the 10mm soon thereafter through a series of tests.

"The most critical, and controversial, issue relating to the selection of a new FBI handgun was that of caliber ... Case accounts of shootings document the fact that subjects receiving fatal, but not incapacitating, wounds have been able to return fire and inflict further damage," according to the 1989 FBI Law Enforcement Bulletin.

Therefore, in September 1987 the FBI put together a consortium of medical and scientific wound ballistics experts. The results of that seminar dictated a course of action. There they examined 9mm and .45 calibers -- but to no avail.

They determined the specifications of the caliber that would best stop the next bad guy.

There were two types of incapacitation decided upon: damage to the central nervous system and significant loss of blood. Given that shot placement in a small, mobile area of the brain would be less reliable than the other option, a caliber needed to be chosen that would be capable of penetrating the body with enough force to pass through "major arteries and blood-bearing organs to ensure timely physiological incapacitation."

Tests were run on a variety of bullets.

There were two criteria: penetration with minimum acceptability at 12" and maximum desirability at 18" and size of the wound. These needed to take into consideration the frontal area of the bullet and depth of penetration. These were tested on several different material types like ballistic gel, heavy clothing, glass, etc.

The seminar tested a Winchester 147 grain subsonic hollow point 9mm round and a Remington 185 grain hollow point .45 round. They also tested a newer 10mm cartridge, ideally sized between the 9mm (.35 caliber) and .45.

The results of the tests on each caliber were a matter of meeting and exceeding the 12" minimum penetration, and each test resulted in a calculated percentage out 40 shots.

• 10mm - 39/40 (97.5 percent)
• .45 37/40 (92.5 percent)
• 9mm 27/40 (67.5 percent)

The standard issue .38 was not in the series of tests to establish a new caliber, but its penetration efficacy was similar to the 9mm, at 67.5 percent of the shots penetrating at or beyond 12".

Although the 10mm and .45 tested similarly in tissue displacement, the 10mm also was deemed more accurate in tests and was therefore chosen to replace the prior standard issue caliber.

In the wake of the FBI's decision, several law enforcement officials sought to use the 10mm as well.

The resulting Smith & Wesson 1076 10mm pistol adopted by the FBI was, unfortunately, doomed from the start, following malfunction and parts breaking. The FBI had originally ordered 10,000 units from the manufacturer, but canceled the order outright after receiving only 2,400, according to Lucky Gunner.

The FBI sought a 200 grain round that traveled at a rate of 1,200 feet per second, resulting in 640 foot pounds of muzzle energy. However, that amount of pressure was hard on the gun and wrist. The FBI administered a less intense 10mm option that is still used by some to this day.

Recently, the FBI switched to 9mm calibers, stating in a report that handgun stopping power is a myth.

The 10mm Pistol Stands Strong Today

The 10mm is still an option at the range for recreational shooters, out in the wilderness for recreational hunters and for those law enforcement officials with a strong wrist. Many are not too bothered by it, and there are options that help .

Just some of the options available today are the Colt Delta Elite, which is the original 1911 chambered in the 10mm cartridge; the Glock 40 Gen4 in MOS Configuration; and the Sig P220 Elite 10mm.

With a recent history as heavy as the bullet hits, the 10mm is a caliber that serves all the needs of its nearly cult-like following.

Basically, it's a heavy bullet that moves fast and penetrates deep.

About The Author Jake Smith (@notjakesmith) is a copywriter in his final year of studying public relations and apparel at the University of Idaho.