Small enough for pocket pistols and fairly easy to find, the 32 ACP presents an enticing option for self-defense minded shooters. But is the 32 ACP enough cartridge to rely upon in a life or death situation?
In short, 32 ACP can offer a good option for self-defense. It’s size means it can easily be paired with an ultra-concealable firearm but it’s not too small to take down a threat. Some shooters may opt for a larger cartridge with more commercially available ammo/firearm options like the 9mm.
Read on to learn what the cartridge is capable with gelatin testing results from the range and a look at the 32 ACP’s place in self-defense and shooting history.
How We Got to the 32 ACP
At the end of 19th century, a typical defensive handgun was a pocket revolver in 32 Short, 32 Long, or 38 Long. All of those guns projected soft lead bullets at moderate velocity. Penetration was poor enough that tales of pocket Bibles and brass belt buckles stopping bullets had some truth to them. The first popular automatic pistols of the 1890s were more like modern PDWs. They used powerful bottlenecked cartridges that looked like scaled-down rifle ammunition.
The 7.63x25mm Borchardt C93 weighed 41oz but was 14in long, and came with a combination holster-buttstock. The slightly more powerful C96 Mauser “Broomhandle” was an ounce lighter and a little shorter, but still designed as a pistol-carbine. A short-recoil locked breech pistol, C96 was expensive — over $1,300 when adjusted for inflation. Less powerful 7.65×21 Swiss Luger of 1898 still used bottlenecked ammunition, and required short recoil locked breech mechanism. As a result, it was a third lighter but no less expensive than the Mauser.
The following year, John Browning entered his first successful automatic pistol, Model 1899 in 7.65×17 semi-rimmed Auto. Today, you probably know that cartridge as 32 ACP ammo.
Browning’s M1899 and the 32 ACP
Browning designed his M1899 around the new straight-wall 32-caliber cartridge. Browning optimized the cartridge for semi-automatic blowback action: it was mild enough to dispense with locked breech, semi-rimmed to allow use in revolvers as well as semi automatics, used jacketed bullets for more reliable feeding and greater penetration, and headspaced on the rim, making the pistols easier to manufacture to sufficient tolerances. Using smokeless powders, 32 ACP ammo massively eclipsed performance of 32 Long in a more compact form. The pistol used an overhanging recoil assembly to reduce muzzle flip at the cost of one cartridge of magazine capacity.
In Europe, FN produced it. In the US, by Colt. At the time of introduction, it cost 1/3 of C96 or Luger, and weighed slightly more than half of the bigger guns at just 22 ounces. It was small enough to fit a typical coat pocket of the time.
Advertising of the early 1900s promoted M1899 with boasts like “amazing power and penetration” which, for a concealable pistol was true enough. A typical .32 revolver was far weaker, and was slower to reload in the bargain. 700 thousand of the original 7.65mm Browning and half-million of the thinner, more streamlined 1908 Colt Pocket Hammerless pistols were made. About 750 thousand Spanish Ruby pistols were made in the same caliber.
During WW1, pretty much every military used 32ACP pistols: the caliber was as mainstream back then as 9mm Luger is now. In the interwar period, 7.65mm pistols were considered standard for many police agencies and a few armies. They were also massively popular with civilian users, being mostly light and inexpensive. Post-WW2, the caliber remained in wide use in Europe, while in the US it was relegated mostly to subcompact pistols. Today, the most popular 32ACP firearm is the diminutive 7oz KelTec P32, ironically a locked breech design.
Assessing Modern 32 ACP Options for Shooters
Was this relatively mild caliber any good as a man-stopper? We put that theory to the range test. First, an anecdote from my own first encounter with 32 ACP. Once upon a time, my girlfriend wanted a Walther PPK of Agent 007 fame. The closest thing to the original available new, thanks to the Gun Control Act of 1968 import restrictions, was Walther PPK/s. Shooting at a country dump, I remember seeing an old vinyl-covered refrigerator door stop every bullet fired from a .22LR Ruger Mk1, with the soft unjacketed bullets failing to get through miserably. A jacketed bullet from PPK/s not only defeated the fridge door but also the back wall and the condenser coils!
Testing 32 ACP for Self-Defense
Recently, I headed to the range with ballistic gel and various barriers to see how 32ACP performed under more controlled conditions.
32 ACP Testing Procedures
For tests, two pistols were used: Colt Pocket Hammerless, a typical compact sidearm with 3.75in barrel, and KelTec P32, the most common subcompact hideout pistol with 2.7in barrel. My target was a block of synthetic get 16in long.
FMJ’s for Maximum Penetration
The original FMJ loads made by Fiocchi, UMC, and American Eagle performed similarly, with 12.5-15″ of penetration. Fiocchi, being a little hotter, penetrated more, while UMC and AE a little less. All made straight-line holes with minimal disruption around the bullet path. A shorter P32 barrel produced slightly lower velocities, so penetration ranged from 10.75″ to 11.5″. From this, we can gather than the original 7.65mm pistols with 3.5 inch to 4inch barrels properly matched to the cartridge.
Hollow Points for Wound Channel
The next load was Prvi Partizan 71gr JHP, an unusually heavy bullet for an expanding 32 ACP. While none of the bullets expanded at all, the longer back-heavy projectiles at least flipped in the wound channel, creating slightly more disruption than ball for the token cost in overall penetration: 12 inches from both Colt and KelTec.
Moving to lighter-weight bullets, I tried an all-copper 50gr Leheigh Cavitator: 10.5″ from Colt, 10.2″ from KelTec. A little cavitation was visible around the bullet tracks. Point of impact was noticeably low. Another 50gr load, frangible Magsafe Defender, used copper jackets filled with pellets suspended in gel. Fired from the longer Colt, these bullets disintegrated spectacularly early in the track, shedding pellets as they went. It made for a pretty gel disruption pattern with only 8″ of penetration by the empty deformed jacket. Far less gel disruption from the P32, but a more respectable 10.2″ depth. It’s interesting that all cartridges I tried cycled reliably in both pistols despite the wide range of weights and velocities.
Conventional hollow points showed the difference between barrel lengths starkly. Colt tossed both 68gr Hydra Shok and 60gr Hornady Critical Defense fast enough to produce expansion to around .38 caliber, with penetration of 9″ and 6.1″ respectively.
The Hydra Shok (left) and Hornady Critical Defense (right) 32 ACP bullets recovered from gelatin.
The P32 showed no expansion with Hydra Shok but 11″ depth, while Critical Defense opened up to .35 caliber and actually went much deeper to 9.3″!
Adding a Cloth Barrier
Except for overheated meth-heads, most likely foes wear clothes. So, I also shot gel blocks covered with a double layer of a Fall jacket. PPU JHP and various FMJ bullets zipped through like the cover garment wasn’t even there, with penetration results identical to bare gel. A harder test pitted the little .32 against 3/4″ wood typical of modern furniture. Fired from the Colt, PPU JHP went 10″ deep. The lightweight Leheigh penetrator surprised me by making it 12.5″. The only theory I have on why it went deeper through a barrier is the flutes filled up with wood pulp, making the bullet more hydrodynamic. Indeed, the penetration path showed little gel disruption along the way. With wood thickness doubled to 1.5″, PPU still got through 9″ of gel.
What The Testing Teaches Us
Conclusions from the testing? Ball ammunition works as designed. Heavy JHP also works well, though it should not be used in P32 because unfired cartridges are so long that they sometimes stick in the ejection port when hand-ejected. High velocity lightweight bullets under-penetrate relative to the desired 12-18″ depth. Compared to a good defensive 9mm Luger load, 32 ACP produces about half the tissue damage. Is that good enough for protection?
On the flip side, 32 ACP can be fired fast and accurately from relatively lightweight pistols. Designed for single-stack magazines, 32ACP can be found in double-stack guns like CZ83, but that is too bulky and heavy for the caliber.
Capacity Considerations
Most 32 ACP pistols hold 7-8 rounds, enough to dose one adult perp but probably a bit light for a serious firefight. On the other hand, a subcompact like P32 remains controllable where a 9mm of the same size and weight would have brutal recoil.
Our Conclusion on Using 32 ACP for Defense
Just like other 32-caliber cartridges like the 32H&R, 32ACP has its niche.
Unlike the unlamented 25 ACP, 32 ACP has remained viable 125 years after its introduction…for limited roles. Lower recoil and milder report make it an excellent choice for people who find larger calibers challenging to shoot.
