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Progress in various areas of technology is often the result of attempts to solve a real or perceived problem. This has led to the development of numerous cartridges, some of which seem to have filled some imaginary need.

Some are given catchy names that often incorporate words such as “super” or “ultra.” In rifle calibers, the voluminous case of a new cartridge may utilize a powder charge that weighs as much as two-thirds the weight of the bullet. For use in handguns, a new cartridge might involve necking a larger case into a smaller caliber or lengthening an existing case. The .357 SIG is an example of the former, and the .357 Magnum is an example of the latter.

EAA offers double-action pistols in 10mm Auto. (Photo: EAA)

The Search for Effectiveness

Except in target shooting, the effectiveness of a handgun depends on bullet diameter and weight, because handguns do not produce velocity anywhere near that given by a centerfire rifle. As a result, calibers such as the .45 Auto and .45 Colt have long been regarded as stoppers. With its moderate bullet diameter, the .357 Magnum is effective, because it combines bullets of sufficient weight with very high velocity. For many years, calibers such as the 9mm Luger were regarded by some as being only marginally effective, but that has changed enormously as a result of ammunition developments.

The 10mm Auto (left) produces much higher energies than the .45 Auto

The search for an effective handgun cartridge led to the development of the 10mm Auto. This .40-caliber case was originally a shortened rifle case designed to hold a .400-inch bullet. However, the stiff recoil, heavy guns and blast were more than some law enforcement participants could handle effectively. This led to the development of a “light” 10mm load, which could be duplicated using a shorter cartridge.

Thus, the .40 S&W was born. It had the advantage in that it could be chambered in pistols that handled the 9mm Luger. It now seems that a cartridge of the size of the .40 S&W loaded to approximately 35,000 psi is still perhaps too much of a good thing in such pistols, and they might develop problems as a result. Even a pistol having the power of the 40 S&W is too much for some officers. The result is that there is a swing in law enforcement back to the 9mm Luger, even for the FBI.

“Except in target shooting, effectiveness of a handgun depends on bullet diameter and weight, because handguns do not produce velocity anywhere near that given by a centerfire rifle.”

The Model 610

The original handgun in 10mm Auto caliber was the short-lived Bren 10, but soon after, Colt introduced the Delta Elite, and Smith & Wesson offered the 1006. The S&W was eventually offered in a more-compact version known as the 1066. With a maximum pressure of 37,500 psi, a 10mm Auto-generates a lot of blast, and recoil is severe, regardless of the size of the pistol.

Given its “magnum” power, a 10mm Auto has a place in the scheme of things handgun, but probably not for duty carry. Instead, the 10mm is an excellent round for the handgun hunter, because some factory loads produce more than 600 ft/lbs of energy—and that, with a rather large bullet.

Although no longer in production, the Smith & Wesson 1006 was one of the earliest pistols to be chambered for the 10mm Auto cartridge.

Recognizing this potential, Smith & Wesson offered the Model 610 revolver in 10mm Auto. My brother took a couple of deer with one, using one shot for each.

In something of a rekindled interest, several manufacturers are now producing pistols in 10mm Auto. Some models are specifically intended for hunting applications, but not all states allow hunting with semiautomatic pistols. Where legal, a 10mm Auto is a good choice for hunting deer, hogs and animals of similar size, but it would also be a good varmint gun.

For many shooters, including me, the favorite caliber for autoloading handguns is the .45 Auto, and there are literally hundreds of models available in that caliber. However, the 10mm Auto is a potent, versatile caliber, and it is offered in the 1911 style. The Smith & Wesson 1006 was a third-generation double-action model with dual safety/decocking levers. That gun and I have been together for many years.

“… given the versatility of the 10mm Auto with handloads, it is one of my two favorite pistol calibers.”

Current 10mm Auto Pistols (not a complete list)

The Colt Delta Elite is one of the most popular 10mm Auto pistols. (Photo: Colt Manufacturing)

Colt Delta Elite

Kimber Camp Guard 10

Kimber Custom TLE II

Dan Wesson Elite Series Titan

Dan Wesson Razorback RZ-10

Dan Wesson Bruin

Dan Wesson Elite Series Fury

SIG Sauer P220 Hunter

Glock 20

Glock 29

Glock 40

EAA Witness

Para Elite LS Hunter

Wilson Combat CQB (and CQB Elite, CQB Tactical LE)

Wilson Combat Classic

Wilson Combat Tactical Supergrade

Wilson Combat Hunter

Ruger SR1911


Loading the 10mm Auto is a straightforward procedure, but care needs to be exercised. First, headspace is controlled by the case mouth making contact with the forward end of the chamber, so cases need to be close to the trim length of 0.987 inch. Also, with powder charges that occupy much of the volume of the case, bullet seating depth is critical. As a result, I keep all cartridges close to the 1.260-inch maximum overall length. Seating bullets deeper causes pressure to increase dramatically.

There is a vast number of bullets available in .40 caliber as a result of the immense popularity of the .40 S&W. Powders that are most often used for loading the 10mm include Alliant Unique, Power Pistol and Blue Dot; Hodgdon HS-6, CFE Pistol and Universal; Winchester AutoComp and WSF; and Accurate No. 5 and 9. Cases are available from several sources.

Numerous powders can be used to load the 10mm Auto, but these are some that work well.

With a pressure limit of approximately 37,500 psi, the 10mm Auto can produce energies in the 600 to 700 ft/lb range, and with bullets of about 150 grains, velocities are high, which means flat trajectory.

I have chronographed the factory Hornady 180-grain XTP at 1,238 fps (613 ft/lbs) and the Winchester 175-grain Silvertip at 1,240 fps (598 ft/lbs). For me, the problem is that with full power loads, the muzzle blast is very severe, and recoil is substantial.

Seating depth is crucial in the 10mm Auto, and overall cartridge length should be 1.260 inch or slightly less.

Those characteristics were responsible for the FBI deciding that the 10mm Auto was a bit too much for many law enforcement professionals, and that led to the development of the .40 S&W, which is short enough to be used in a smaller, lighter pistol. But, as a fellow shooter used to say, “You can always load a big one down, but you can’t always load a little one up.”

I have taken that principle to heart when loading for the 10mm Auto. All the loads listed in the sidebar functioned flawlessly and provide as much power as I need. They also delivered all the accuracy I can get from a handgun.

All in all, given the versatility of the 10mm Auto with handloads, it is one of my two favorite pistol calibers.

The explosive effect of a 135-grain Nosler hollow point hitting a gallon jug filled with water


Loading Data and Results for 10mm Auto Loads


Case Overall Length (inches)


Load 1

Load 2

Gr. Vel. Gr.


135-grain Nosler HP Federal 1.258 CFE Pistol 8.6 1,259 9.0 1317
135-grain Nosler HP Starline 1.255 True Blue 9.0 1,235
150-grain Nosler HP Norma 1.260 AutoComp 7.8 1,221 8.4 1298
150-grain Nosler HP Norma 1.256 Power Pistol 7.0 1,147 7.4 1227
155-grain Hornady XTP Federal 1.259 CFE Pistol 7.9 1,183 8.3 1233


155-grain Hornady XTP Hornady 1.260 Power Pistol 8.2 1,201
155-grain Speer Gold Dot Norma 1.254 Blue Dot 9.7 1,133 10.1 1,194
155-grain Berry HBRN Hornady 1.260 Accurate 5 8.0 1,002 8.4 1,076
165-grain Speer Gold Dot Norma 1.256 Power Pistol 7.0 1,031 7.4 1,077
165-grain Rainier HP Hornady 1.255 Accurate 5 7.8 1,028 8.2 1,068
180-grain Hornady XTP Norma 1.260 AutoComp 6.8 1,086 7.2 1,131
180-grain Berry HP Hornady 1.257 Accurate 5 7.7 1,031 8.1 1,081

Notes: Velocities were measured at 10 feet from the muzzle using a Competition Electronics ProChrono chronograph. Velocities are shown as the average for five shots.


Editor’s Note: A version of this article first appeared in the December 2017 print issue of Gun World Magazine.