When it comes to the 10mm vs .45 ACP, application decides the winner.

Points to consider when deciding between the 10mm vs .45 ACP:

  • Cartridge application
  • Recoil sensitivity
  • Potential need for fast follow-up shots
  • Handgun size (.45 has more compact options)
  • Average engagement range
  • Price per round (one is a bit more spendy than the other)

The quest for the perfect handgun is ongoing and always evolving. In recent years, at least among those with a yen for powerful semi-automatic pistols, a gauntlet of sorts has been laid down: 10mm vs .45 ACP. Funny thing, go back 40 years or so and this debate wasn’t really … well … a debate.

Proof of the 10mm's popularity, Colt has reintroduced its classic Delta Elite, now with a rail.
Proof of the 10mm’s popularity, Colt has reintroduced its classic Delta Elite, now with a rail.

The new kid on the block, an oddity at that, the 10mm never really got out of the shadow of the grand old .45 ACP. Closing in upon its centennial birthday, John M. Browning’s masterpiece stood alone when it came to big-bore semi-auto cartridges. The 10mm, with all its potential, looked ready to fade away from early glory, following the likes of the .44 Auto Mag and other powerhouse semi-auto cartridges.

Then a funny thing happened. In the early years of the 21st Century the 10mm rose from its ashes. And while Col. Jeff Cooper’s darling has never become quite the belle the .45 Auto has remained, it certainly has turned heads enough to become a consideration among those who yearn for big and bad.

So, in the grand battle of 10mm vs .45 ACP, which is it to be? The answer — like everything in the gun world — isn’t as clear-cut as simply jumping on one team or the other. Both are excellent, with plenty of crossover application. But at their quick, each excels a little more than the other at certain tasks.

For more than a century the .45 ACP has been a standby, and likely will be for a century more.
For more than a century the .45 ACP has been a standby, and likely will be for a century more.

If your answer isn’t “Give me one of each!” then you need a long hard chew on what you plan to do with your new 10mm or .45 ACP before getting one. Doing so, you’re more likely to find the brute that best serves your needs. 

.45: Close-Quarters Star

Purpose designed as a man stopper, the .45 ACP has shined in the role for more than century. Most know the story, at the turn of the 20th Century the .38 Long Colt had a poor showing against determined opponents in the Moro Rebellion. In turn, the U.S. Military went searching for a more substantial replacement. Looking forward by looking back, it was decided something along the lines of a .45 Colt would fit the bill.

A match made in heaven, the .45 ACP and M1911.
A match made in heaven, the .45 ACP and M1911.

As luck would have it, John Browning was working on the perfect cartridge at the time — the .45 ACP used in the Colt 1905. Eventually matched with his legendary 1911 pistol, the cartridge and handgun went on the make history. Both served the U.S. Military with distinction for the better part of the 20th Century, including both World Wars and numerous smaller conflicts. Standard bearer statue achieved, it continues today as a favorite of armed citizen and a law enforcement alike, offering manageable power with proven results.

Aside from its ability to dissuade an attacker with sizable chunks of copper-jacketed lead, the large-bore round won favor because of a less recognized asset — it isn’t a bear to shoot. Certainly out of most pistols it generates more recoil than say the 9mm, but not a universe more. Give time, practice and willingness to learn, only the truly recoil sensitive are nixed from the .45. The vast majority of other shooters can master it.

Get An Edge On The 10MM:

The effort to become competent with the cartridge out of the many pistols chambered for it is worth it. In the skilled hands, the .45 ACP absolutely sings. Watch a practical pistol or steel challenge match and consider, the majority of the pistols being accurately redlined are chambered for the short, fat cartridge.

How does the .45 ACP achieve the seemingly contrary ends of power and manageability? Simple, it’s a low-pressure cartridge that shoots heavy bullets slowly. Take, for instance, a relatively average .45 ACP self-defense round, such as a Remington’s 230-grain Golden Saber. It leaves the muzzle at 875 fps, yet at this velocity it’s working with 391 ft-lbs of energy. Not blistering hot by anyone’s standards, but within typical self-defense ranges it has more than enough punch to get the job done. The Achilles’ heel of the cartridge, the further you have to shoot, the more difficult it is to achieve accuracy — the .45 drops, a lot, fairly quickly.

From Cartridges of the World, 15th Edition.
From Cartridges of the World, 15th Edition.

As a self-defense option, particularly with today’s bullets, the .45 is Mojave rattler potent. While research is required to ensure satisfactory penetration from a defensive round, most bullets they’re loaded with have mind-blowing expansion potential. At the extreme end, such Winchester’s Ranger T-Series, the projectiles are fully capable of mushrooming to 1 inch in diameter. That equates to undeniably devastating wound channel.

Furthermore, the .45 ACP’s common use also gives it the advantage of ample handguns and ammo options. The iconic 1911 still soldiers on, not only made by Colt, but a slew of other manufacturers — Kimber, Springfield, Remington, SIG Sauer and many more. Additionally, the .45 is also available in a number of other makes and models, such as the Springfield XD, Smith & Wesson M&P, Glock (21, 30, 36, 41) and nearly everything else not considered a pocket pistol. There’s even a healthy selection of compact pistols in the caliber, given the .45’s popularity for concealed carry. Rounds for those guns? If a store sells handgun ammunition it is a safe bet they’ll have .45 — at the bare minimum ball.

10mm: Multitalented Masterpiece

Famed firearms instructor and all-around firearms guru Col. Jeff Cooper set out to do the impossible in the early 1980s — improve on the .45 ACP. A fan of the cartridge, he aimed to design an option that had superior ballistics and improved barrier penetration performance. Inspired by a wildcat, the .40 G&A, Cooper believed he had found a model to dethrone the king.

S9137-10mm-Auto-
Ready for the field, a Glock G20 Gen4 SF hunting set up with a 6-inch barrel and Leupold Delta Point reflex sight.

In concept, his “.40 Super” would pitch a 200-grain bullet at velocities in excess of 1,000 fps, more than enough to dust the .45 on all counts. Roughly, it would achieve 20-percent more velocity at the muzzle than the .45 and flirt with doubling its energy. Hard hitter fails to capture Cooper’s ultimate goal. The idea eventually transformed into the 10mm and became a reality when he teamed up with gunmaker Dornaus & Dixon and Swedish ammo manufacturer Norma. As good as it looked on paper, in execution the “Big Ten” stumbled out of the gates.

The first gun chambered for the round — the Bren Ten — became notorious for its production issues and was priced like it was cast from gold. Then the 10mm round itself had its issue. By all accounts, it lived up to Cooper’s billing. The original 200-grain loads screamed from the muzzle at 1,200 fps, with a bone-crushing 759 ft-lbs of energy. In FBI testing, a 170-grain JHP from Norma ended up with the best “Wound Value” score. But it proved a handful.

Hot whiplash to shoot compared to semi-auto pistol at the time, 10mm shot-to-shot split times were painfully long. Not exactly ideal in the FBI’s eyes, who adopted it for a short time in the 1980s and 90s. And the recoil was none too easy on the guns either, with a tendency to break them down before their time. The final nail in the coffin — at least in professional use — was a mid-velocity round that achieved the same terminal performance, while creating a highly shootable 10mm. The thing was, less powder meant excess case, a problem solved with the advent of the .40 S&W.

Bren Ten Handgun
The Bren Ten Handgun, designed by Jeff Cooper, enjoyed a lot of buzz in the 1980s. However, the 10mm pistol was a bulky and expensive product in a market full of small and cheap alternatives.

Colt with its Delta Elite and Glock with its G20 and 29 — along with a handful of diehard ammo makers — kept the 10mm from slipping into obscurity in the dry years after the FBI abandoned the caliber in the mid-1990s. Then, almost miraculously, interest in the 10mm peaked again after the turn of the century and in recent years has flirted with fever pitch. Difficult to say why shooters have re-kindled love for the nearly forgotten handful (most likely versatility), but in the past few years the market has responded.

Though not as widespread as the .45, nearly all the major gunmakers and a few boutique outfits offer the 10mm. Of the more notable are the Ruger SR1911, SIG Sauer P220, Remington R1 Hunter, Dan Wesson Bruin and Springfield Armory 1911 TRP RMR. Colt even dusted off its Delta Elite and Glock added the G40.

An interesting twist, while the 10mm is still popular as a self-defense option, it has punched a toehold in the hunting world. Reaching further with a substantial payload, the cartridge has been found chasing whitetails up north and hogs down south. Some even used as bear insurance out west.

From Cartridges of the World, 15th Edition.
From Cartridges of the World, 15th Edition.

Given varied applications, ammunition selection has blossomed along with its popularity. Since it fills certain niches, not every round is suitable for every application. A sledgehammer hunting round, such as Buffalo Bore’s 220-grain Heavy Outdoorsman, will make a hole in an attacker, no doubt. But if pass through is a concern, it might not be a wise choice for self-defense.

Who Wins Out In 10mm vs .45 ACP?

If you’re in the market and weighing the 10mm vs .45 ACP, the question shouldn’t be “Which one should I buy?” That will get you nowhere. To get the right cartridge and the gun to launch it you should ask yourself, “What do I plan to use it for?” Arguably anticlimactic, fully admitted, but most sober decisions play out that way.

Ruger's 10mm SR1911
Ruger’s 10mm SR1911

Economical and excellent up close, the .45 ACP is an exceptional choice for a self-defense, plinking and competition. The cartridge hits hard close range, makes big holes and has a proven track record saving lives. A more lenient recoil, it is also easier to become competent within a shorter amount of time and potentially is a faster option if follow-up shots are a concern. Less recoil also makes it a more logical choice if you’re looking for a compact carry gun.

Given its long lifespan, there are simply more pistol options to choose from for the .45 ACP. In turn, you have a greater likelihood of finding exactly the right pistol for your purposes, whatever they might be. And in the long run, it will prove cheaper to shoot. Ammo, at least at time of writing, is abundant and easy on the pocketbook. There are a lot of options, including self-defense, that falls below the 50-cents per round mark.

Conversely, if you have a yen for a handgun that reaches out, hits hard and — if you happen to reload — has more room to work with, your money might be better spent on a 10mm. Definitely, it’s the choice if you’re aiming at handgun hunting or need protection against four-legged predators, instead of simply two. Not that the “Perfect Ten” isn’t a capable self-defense cartridge — it is. Only it requires more time and effort to become truly proficient with, outside its lightest loads. This is especially the case if you opt for a smaller-framed model.

Smith & Wesson M&P 2.0 in .45 ACP.
Smith & Wesson M&P 2.0 in .45 ACP.

Given the cartridge is in its renaissance, you’re also limited in your pistol choices. Certainly, there are more options every year, but they are a fraction of what’s available for the .45. You don’t get to be as choosy. Things are brighter on the ammo horizon, there are more choices, and, as mentioned before, it perhaps has more handloading potential. Overall, a 10mm is tougher on the pocketbook. There are options less than 50-cents per round, but mostly range fodder. The self-defense stuff quickly gets up to $1 and above each trigger pull.

In either case — and like with all guns and cartridges — you should practice due diligence. Not only consider what you plan to use your 10mm or .45 ACP for, but also test drive the makes and models that get your trigger finger itching. Only after you drop the hammer will you know if you have found the right gun and cartridge. Do enough legwork and whether you settle on 10mm or .45 ACP, you will find either rock solid if they match up with your needs.


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