The Heizer PKO 45

Thin Is In

The Heizer PKO 45 is easy to tote and easy to retrieve. For proper power in a pocket chassis little else compares.

Amidst a veritable sea of well-reasoned pistols littering the defensive handgun landscape, the Heizer PKO 45 is refreshingly different. Cut from a solid slab of stainless steel and sporting a remarkably anorexic architecture, the PKO 45 puts .45 ACP power into a package breathtakingly trim. Unlike 95 percent of the handguns on the planet, the PKO 45 doesn’t claim parentage tracing back to John Moses Browning. Old JMB contrived the gun’s man-stopping cartridge of course, but this skinny little heater hails from fresher spaces.

The pistol comes with a flush-fitting 5-rounder mag as well as an extended 7-rounder.
See the little forward grip safety just below and behind the trigger guard?

Feeding Obsessions

It’s the very beating heart of our modern culture. It fills tabloids, sells clothes, saturates our senses and drives a certain lamentable percentage of us to the brink of suicide and beyond. As we hurdle headlong into the Information Age we Americans are obsessed with being skinny.

It’s not always been thus. There was a time in human history when being thin meant you lacked sufficient food. Back then having a little meat on one’s bones indicated a certain commendable social status. Not so much anymore.

A plastic surgeon buddy once opined he treated depression with a knife. We cut stuff off, build other stuff up, and slurp out unwanted fat with a tool. Butts, boobs, bellies and brows serve as both palette and canvas for the plastic surgeon with talent. Given our utter obsession with almighty skinniness, is it any wonder this spills over into our working firearms? In the Heizer PKO 45 we find a reliable defensive handgun that embodies this ethic. The end result can be a handful on the range, but it’s small enough to be there when you need it.

The rear sight’s a high-visibility red fiber optic unit that
mates up with a green fiber optic front sight.

The fixed barrel of the PKO 45 is below the recoil spring assembly.
Note the teeny, tiny rail section on the dustcover below it.

Radically Different

Heizer has a storied history of packing insanely powerful cartridges into sundry pocket pistol chassis. Each of their previous little cellphone-sized pistols included a tilting barrel, ultra-slim architecture and a trigger set on roller bearings. Chambering options include .410/.45LC, .223 and, believe it or not, 7.62x39mm. These guns put the “holy” into “holy snot.”

The rifle caliber versions include progressively ported barrels to help ameliorate recoil. Sights are fixed and tiny, but don’t fret overly. (I’ve shot these guns. At reasonable ranges if you don’t connect with the bullet the muzzle flash will reliably set your assailant on fire.)

The newest semiautomatic Heizer PKO 45 rethinks the defensive handgun. The slide is cut from a solid piece of steel and overhangs the barrel, and the guide rod is on the top with the barrel below it. The barrel itself sports a square external profile grooved longitudinally to minimize weight while looking cool. Everything that interfaces with your skin is nicely smoothed. All the controls are intentionally crafted to melt into the exterior of the gun so there is nothing to snag.

The machining of the well-made PKO 45 is truly artistic. Note the round
ready to feed from the magazine showing through the open ejection port.

Weirdly Awesome

The Heizer PKO 45 is what would happen if the Terminator mated with a waffle iron. Broad brush, the gun is fabulously well executed. A well-made firearm just sits a certain way in the hand, and the workmanship on the PKO 45 is clearly top-flight throughout.

Festooned with gripping grooves and scalloped bits, the gun sports an unnaturally low bore axis along with a nice single-action trigger. The low-profile sights include fiber optic inserts both front and rear, and the gun sports an unobtrusive bilateral manual safety. The magazine release is in the expected spot, and there is a small left-sided slide stop if you’re man enough to run this powerful little gun fast. Additionally, there is a splendidly unobtrusive reverse grip safety on the front strap which is just neat as can be.

The gun feeds from modified 1911 magazines and comes with two. The abbreviated 5-round sort fits flush with the bottom of the frame. An extended version with a polymer sleeve packs seven in the box and is much more comfortable on the range. You’ll inevitably tote it with the small mag but practice with the big one. The mag release button is almost flush with the frame so you have to be intentional about it. There is a loaded chamber indicator built into the right aspect of the which can be seen as well as felt.

The frame is formed of two halves held together with plenty of flush-fitting hex screws. The approach to the trigger is nicely beveled on both sides, and all the sharp edges have been mercifully excised. There is technically a tiny piece of rail on the front of the frame, but it’s frankly the most minuscule I have ever seen. There’s likely a light out there someplace small enough to fit, but you may have to look among your GI Joe action figure accessories to find it.

Stripping the PKO 45 involves locking the slide to the rear and then rotating and removing the takedown latch. Keep your finger over the end of the guide rod lest you launch it into the mesosphere. Slip the guide rod assembly out the front and then remove the slide to the rear. The mechanics of the gun are the very image of simplicity.

Given its rigid barrel and crisp single-action trigger the PKO 45 shoots nice and straight.
These tidy clusters printed from a simple rest at seven meters.

Everything Is Physics

In a perfect world the ideal defensive gun would be lightweight, powerful, accurate, concealable, reliable, comfortable and simple. In this perfect world I also wouldn’t have to work for a living, people would treat others with kindness, recreational machine-gunning would be a recognized competitive sport replete with professional cheerleaders and peanut M&M’s would rain down spontaneously from the heavens. However, nothing about our world is even remotely perfect. Everything in life, to include our defensive handguns, is a compromise.

The PKO 45 is only 0.80″ across. Heizer claims theirs is the thinnest production .45 ACP handgun in the world, and I have no reason to doubt this. Do the math. Subtracting 0.45″ for the cartridge case only leaves 0.175″ worth of handgun on either side. It really can’t get any thinner.

Pressure is force per unit area. A modest force over a small area can produce a lot of pressure. Conversely, an impressive force spread over a wide area can produce very little pressure. Ergo, a 100-lb. supermodel in stiletto heels creates a massively greater ground pressure than does a 136,000-lb. M1 tank with its broad steel tracks. As it relates to the PKO 45, this means the little gun’s prodigious recoil impulse is spread over a relatively small area.

Will would feel completely safe being protected by the itty-bitty PKO 45.

Trigger Time

Make no mistake, this gun isn’t for fun. The action is direct unlocked blowback. This means all the .45 ACP horsepower transmits straight back into your sensitive mitts. However, the end result is preternaturally concealable and thoroughly reliable. The action is so simple there’s just not much on the gun to fail.

The slide is easy to grip though the recoil spring is necessarily stout. The third finger presses the grip safety naturally in the manner of a second trigger. The bilateral manual safety is nicely positioned for easy manipulation. Learning to use it responsibly is the reason we train.

The short magazine is optimally concealable but leaves your fifth finger flapping in the breeze. Given the energy of the cartridge the longer 7-round version is much more pleasant. However, should you ever deploy this little pocket howitzer for real, you won’t care how comfortable it is in your hand.

Running the PKO 45 unleashes a lot of power from a relatively small platform and is fairly explosive. The same comfortable-seeming recoil impulse in your favorite tuned 1911 is now distributed over maybe half the area in the PKO 45. While hardly recreational, the effect does not cross the boundary into self-abuse. Most any .44 Magnum is markedly worse. I’m a skinny guy, and I managed it fine. You do have to hang onto the gun, however, particularly with the stubby magazine in place.

The barrel is rigidly affixed to the frame, so accuracy is very nice for its genre. Hornady’s Critical Defense 180-gr. FTX rounds printed four of five as a big jagged hole at 7 meters. The radical orientation of the barrel underneath the guide rod places the line of recoil into the web of the shooter’s hand. This feature mitigates muzzle flip and transforms the impulse into more of a push than a twist.

At proper defensive ranges the PKO 45 runs quickly and well. Follow-up shots are fast, and magazine changes are not bad for what’s in essence a .45 ACP pocket gun. The controls are well reasoned if small. However, this isn’t a service pistol. This is a deep cover defensive weapon that comes out fast and offers instant fire superiority.


So what’s the PKO 45 really like? Viscerally speaking I would rate it someplace between running an orbital sander and stubbing your toe. The gun is not quite painful, but it’s hardly fun.

At 21 oz. the PKO 45 feels surprisingly heavy. However, this is still roughly half the weight of a 1911. A little mass is a welcome addition when trying to tame the esteemed .45 ACP in such a tidy package. The gun tucks easily into a purse, the center console of your car or inside your belt. This powerful .45 ACP gun will ride comfortably in most any holster that will carry a GLOCK 43.

Everybody and their aunt churns out locked-breech, recoil-operated plastic pistols these days. Only Heizer makes something like this. Recoil is not to be discounted, but the PKO 45 is easier to pack than most any other .45 ACP gun on the market. The best defensive pistol is always the one you have on you when you need it. If it’s too big or too heavy you will invariably leave it at home. This puts the Heizer PKO 45 in a class of its own. 

For more info:, Ph: (888) 965-0972.

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