Skip to main content

The Mouse Gun That Roared

The Mouse Gun That Roared

The .32 bullet, which is actually closer to .31, expanded to nearly .53 caliber.

When I was a youngster, our class put on a great play titled "The Mouse that Roared." Perhaps you remember the movie starring Peter Sellers. This blast from the past came to mind as I began looking over a new cartridge. You'll see why as you read on.

At the 2002 NRA Annual Meetings in Reno, Nevada, North American Arms and Cor-Bon Ammunition announced a new cartridge that would soon be available for the little NAA Guardian semi-auto. Prior to this time, the stainless steel Guardian had been available chambered for the old .32 ACP round while a slightly larger version took the .380 ACP.


The 60-grain Jacketed Hollowpoint penetrated 6 1/4 inches of ballistic gelatin.

Putting things in small packages has a downside, of course. It comes as no secret that as barrels are cut down to fit small frames, ballistics suffer. The rule of thumb suggests that 50 fps are lost with each inch of barrel that is removed. By the same token, cartridges that "work," to some degree all rely on a mix that includes substantial velocity. The very best rounds for defensive use tend to hit 1,000 fps or substantially more in many cases. Generating 1,000 fps or more from a sub 3-inch barrel isn't easy.


Enter the .32 NAA. As reported by Clair Rees in last November's issue of Handguns in an exclusive story, the new mouse that is making considerable noise hinges on a necked-down .380 ACP that launches a 60-grain .32 caliber bullet at more than 1,200 fps out of a 2 1/2-inch barrel. Much of the developmental work took place under the watchful eye of Ed Sanow, co-author of Handgun Stopping Power, Street Stoppers and Stopping Power, a series of books about real world ballistics. Sanow and Evan Marshall have spent a good portion of their careers looking at cartridges and how they perform on the street.

Bottleneck cartridges work well in semi-autos because they are shaped to feed naturally and headspace on the shoulder rather than the case neck. A bottlenecked cartridge can include a solid crimp, eliminating the possibility that a bullet might be dislodged as it is chambered.


The .32 NAA is based on a full-length .380 ACP case. Measuring .680 inches in length, the little hot rod features a short neck that is designed to securely hold a 60-grain .32 caliber JHP.


Typical of Cor-Bon loads, the .32 NAA round is designed for serious business. Launching a 60-grain JHP bullet, Cor-Bon predicted 1,200 fps and 192 ft-lbs of energy and the combination exceeded Cor-Bon's predictions. Twenty rounds averaged a blistering 1,204-fps with an extreme spread of 69 fps and a standard deviation of 19 fps on the Oehler 35P. The combination accounted for 193.09 ft-lbs of energy.

After encountering the gelatin, this recovered 60-grain bullet weighed 46.6 grains with a 3.5-grain fragment.

While accuracy isn't often measured with handguns of this size, I managed to hold the little Guardian tight enough to account for five, 5-shot groups that averaged less than two inches at seven yards. With the sights aligned at the top of the target, the NAA/Cor-Bon team stayed within the confines of the 3-inch target most of the time.

The combination is impressive in ballistic gelatin, as well. Fired at the routine 10 feet, the little 60-grain slug went exactly where directed and it penetrated the carefully prepared ballistic gelatin 6 1/4 inches. As can be seen in the accompanying photos, the bullet path was straight with a good permanent cavity as well. The recovered bullet weighed 46.6 grains but a 3.5-grain fragment dropped from the bullet as I pulled it from the gelatin. The recovered bullet measures .528 inches or nearly 53 caliber, exhibiting 165 percent expansion. With 72 percent weight retention, the performance is good here as well.

I've long appreciated velocity, having taken hundreds of called predators with a .17 centerfire loaded with 20- to 25-grain bullets. Out of a handgun these lightweight bullets can be loaded to just more than 3,400 fps and they'll do more than 4,000 out of a rifle. Typically, they strike like lightning while never exiting the target and doing no pelt damage. Indeed, the magic of the .17 centerfire hinges on velocity.

In the handgun world, where backup arms are considered, the new .32 NAA effort of NAA and Cor-Bon looks like a winner. This new hot-rod exceeds 1,200 fps even when limited by the Guardian's stubby 2 1/2-inch barrel. Cor-Bon's hottest +P .380 load can't do 1,000 fps from the same-length barrel. Run-of-the-mill .380 loads tend to generate velocities running from 820 to 870 fps, in similar length barrels.

The .32 NAA is based on a .380 ACP case necked down to accept .32 ACP bullets.

Featuring limited but adequate penetration and excellent velocity, the .32 NAA looks like a nearly ideal combination for such a small arm. Combined with faultless feeding, I'd bet on this combination.

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

See More Recommendations

Popular Videos

Handgun Basics

Handgun Basics

SIG Academy's Hana Bilodeau joins Rich and Jim to discuss the essential skills all handgunners should master.

Pistol Skills Drills - Hardball

Pistol Skills Drills - Hardball's Headache

The Hardball's Headache pistol drill is very similar to the El Presidente drill with a higher level of difficulty due to two added twists.

KelTec P17 22LR Pistol – Feature Packed, Accurate & Fun to Shoot

KelTec P17 22LR Pistol – Feature Packed, Accurate & Fun to Shoot

If you're in the market for a 17-round, compact .22LR pistol that's feature packed, then the P17 is definitely an option for you. At less than 14 ounces fully loaded, and barely longer than a dollar bill, the P17 is concealable for pretty much anyone. The threaded barrel, Picatinny-style accessory rail, ambidextrous safety, ambidextrous magazine release and three (3) 16rd magazines come standard. That's a lot of value added in such a small package.

KelTec CMR30 22WMR Review - Compact, Versatile & Fun to Shoot

KelTec CMR30 22WMR Review - Compact, Versatile & Fun to Shoot

Designed for lightweight, low recoil accuracy, the CMR30 .22 WMR features a nice, single-action trigger, ambidextrous dual non-reciprocating operating handles, ambidextrous safety and heel catch magazine release. The KelTec CMR30 is a .22 Magnum carbine that holds 30 rounds in each of its two flush-fit magazines. That's a lot of firepower for a 3.8-pound, semi-auto, collapsible truck gun. It comes out of the box as you see it, including Magpul sights and ambidextrous, non-reciprocating dual operating handles. She's a straight blow-back tack driver that delivers a ton of fun.

See More Popular Videos

Trending Articles

Small, compact semi-auto pistols are popular with concealed-carry firearm buyers, and these two models – the KelTec PF9 9mm and the Ruger LCP II .22LR – are no exceptions. They are effective for personal protection but only if you put in the time to practice.Compact Carry Pistols Are Effective With Practice Training

Compact Carry Pistols Are Effective With Practice

Handguns Staff - August 14, 2020

Small, compact semi-auto pistols are popular with concealed-carry firearm buyers, and these...

As you will learn in this detailed review, the Smith & Wesson M&P Shield EZ 380 (manufacturer SKU # 180023) is an easy-racking, soft-shooting pistol.Smith & Wesson M&P Shield EZ 380 Review Compact

Smith & Wesson M&P Shield EZ 380 Review

James Tarr - November 06, 2018

As you will learn in this detailed review, the Smith & Wesson M&P Shield EZ 380 (manufacturer...

Available in .38 Super, 9mm and .45 ACP, the Ed Brown 1911 Executive Commander offers a terrific balance of weight, power and shootability.Ed Brown 1911 Executive Commander 9mm Review 1911

Ed Brown 1911 Executive Commander 9mm Review

J. Scott Rupp - May 08, 2019

Available in .38 Super, 9mm and .45 ACP, the Ed Brown 1911 Executive Commander offers a...

The SIG SAUER P365 (model # 365-9-BXR3) may just be the subcompact 9mm against which all others will be judged.SIG P365 Review Compact

SIG P365 Review

James Tarr - October 31, 2018

The SIG SAUER P365 (model # 365-9-BXR3) may just be the subcompact 9mm against which all...

See More Trending Articles

More Ammo

Remington's newest defense load is now available commercially.The Black Belt - Remington's Newest Defense Load Ammo

The Black Belt - Remington's Newest Defense Load

James Tarr - January 02, 2019

Remington's newest defense load is now available commercially.

Federal Punch ammo is designed for the concealed-carry and self-defense pistol market. Check out the video for a performance test using ballistics gel.Federal Premium Punch Defensive Handgun Ammo - TESTED Ammo

Federal Premium Punch Defensive Handgun Ammo - TESTED

James Tarr - August 19, 2020

Federal Punch ammo is designed for the concealed-carry and self-defense pistol market. Check...

SIG SAUER, Inc. introduced the newest addition to the SIG SAUER Elite Ammunition product line ' the high-performance M17 9mm +P ammunition.SIG SAUER Introduces M17 9mm +P Ammunition Ammo

SIG SAUER Introduces M17 9mm +P Ammunition

SIG SAUER, Inc. - December 13, 2018

SIG SAUER, Inc. introduced the newest addition to the SIG SAUER Elite Ammunition product line...

The Syntech Defense bullet utilizes a hollowpoint design with three nose segments and a one-piece core designed for deep straight-line penetration and maximum energy transfer.Federal Syntech Defense Ammo Ammo

Federal Syntech Defense Ammo

Brad Fitzpatrick - December 18, 2019

The Syntech Defense bullet utilizes a hollowpoint design with three nose segments and a...

See More Ammo

Magazine Cover

GET THE MAGAZINE Subscribe & Save

Digital Now Included!

SUBSCRIBE NOW

Give a Gift   |   Subscriber Services

PREVIEW THIS MONTH'S ISSUE Arrow

Buy Digital Single Issues

Don't miss an issue.
Buy single digital issue for your phone or tablet.

Buy Single Digital Issue on the Handguns App

Other Magazines

Special Interest Magazines

See All Special Interest Magazines

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Phone Icon

Get Digital Access.

All Handguns subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit mymagnow.com and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now