The introduction of the 10mm Auto gave magnum power to the 1911 platform, but as the Colt Delta Elite demonstrated it just wasn’t up to the task. Heavy-bullet loads with their high pressure and recoil caused cracking of the frames and rails. The platform can be beefed up to handle it, but stock guns? The best you can hope for is a seriously curtailed service life.

In 1997 Peter Pi, the founder of Cor Bon, designed a 10mm that would avoid these issues and with light-bullet loads would equal the 10mm’s power. His reason for doing so was that hollow-point bullets require velocity to expand, and bottle-necked cartridges tend to feed well in semi-automatic pistols.

To make a long story short, it worked. Mostly. Both cartridges can comfortably push a 135gr. bullet to 1450fps. for 630 ft./lbs., or a 155gr. bullet to 1250 fps. for 538 ft./lbs. of energy. But as the bullet weights increase .400 Cor Bon lags behind. It’s a matter of pressure; .400 Cor Bon has a lower maximum pressure than 10mm Auto, and you run up against that limit trying to push heavier bullets to 10mm velocities. Many experts in the field say 165gr bullets are pretty much the limit for high-performance loads in this cartridge. People have run 180gr. loads, but these resemble .40 S&W more than 10mm.

People have reported varying degrees of success using drop-in barrels in 1911s, and if you plan to shoot a lot a heavier recoil spring might be a good idea. I’ve read several reposts of people tearing up their 1911s firing this cartridge, but when I looked into these cases the symptoms were exactly what I’d expect from an improperly-fitted barrel in a .45-caliber 1911, so this is hardly conclusive. If you are not intimately familiar with the platform fitting any replacement barrel is probably best done by a professional.

A few guns have been produced in this cartridge, but for the most part it has been an aftermarket modification for 1911-pattern guns. The 135gr bullets have significant authority when used on small game, and the heavier bullets have been used successfully on medium-sized game at limited ranges.

Cor Bon, Underwood and others still produce .400 Cor Bon ammunition, but by and large it is viewed as an answer for a question no one asked.

Why .400 Cor Bon?

So, what attracted me to this cartridge? Mostly the fact that I was going through Pinto’s Guns discount section and there was a set of reloading dies for $10. I thought, ‘Hell, why not?’

I played around with it a bit, and forming brass is dead simple; run .45 ACP brass into the resizing die and .400 CB brass emerges. I had the best results by inserting the shell-holder in the ram, running it all the way up and screwing the die in until it made contact with the shell-holder. I had a few 10mm bullets on-hand, so I looked up load data and made up some cartridges. 155gr. JHPs at 1250 fps. making 538 ft./lbs. at the muzzle seemed a good place to start.

I looked up replacement barrels, which are not unduly expensive, and filed it as a ‘to do’ and forgot about it for several months. Recently I remembered and ordered a barrel from SARCO for about $60. It claims to be ‘drop-in,’ and while early barrels from them were poorly reviewed it was generally agreed that they had largely rectified those issues. For the price I decided to take a chance on it.

When it arrived it actually looked better than their picture on the web-site. It came without a link, so I removed the one from the gun’s current .45 ACP barrel and used that as a starting point. I hesitantly re-assembled the gun and checked the fit…

OK, understand this: when my eyes see ‘drop-in’ my brain sees ‘gunsmithing required.’ So I was quite surprised when the barrel fit and appeared to function perfectly. Huh. OK, that bent my reality a bit but I was willing to roll with it. Tentatively. I took it to Champion Arms with the ten rounds I had on-hand and…

It worked. Flawlessly. Perceived recoil was similar to .45 ACP, accuracy was fine and when I took the gun home and disassembled it everything looked… fine. OK then. Bob Rogers sent me some 155gr. TMC-FP bullets and Jim Bensinger sent me some Gold Dot hollow-points. I loaded these over 8.0gr. of Unique with a CCI 300 primer and headed back to the range.

Shooting it

At the range I discovered some interesting things, not the least of which was that the magazines I had brought suck. These are something I’ve had lying around and have been meaning to try out, and because I’m an idiot I thought it would be a good idea to test them and the ammo at the same time. They weren’t catastrophically bad, but the first round out sometimes nose-dived and they don’t lock the slide open.

OK, two different bullets, same weight, similar profiles, same load. You’d expect them to perform similarly, right? You must be new here…

Starting with the 155gr. TMC-FP I discovered, to my dismay, I was having trouble producing a respectable group at seven yards. I tried some rapid-fire and got these results:

OK, Normally I would blame me, but the eagle-eyed among you may have noticed something…

Yep, about half the bullets are yawing badly, and there’s a couple of full keyholes. This caused immediate paranoia; it hadn’t happened on my first test. Had something gone wrong?

Nope, not with the gun anyway. Five shots in five seconds with the 155gr. Gold Dots went just fine. Not sure what’s happening, but the TMC bullets do not like this load.

Shooting this round is not at all unpleasant. Recoil is notably snappier than .45 ACP, but recovery time between shots is unaffected, and further efforts produced similar results. So with the right bullet and load it seems to work a treat. Powerful, easy to shoot and should have a nice flat trajectory.

Reloading

There’s plenty of load-data for jacketed bullets, and I didn’t really find any for cast bullets. I’ll be working on that…

Reloading .400 Cor Bon isn’t all that tricky. Since the cartridge headspaces on the shoulder trimming the brass isn’t a major concern. Care must be taken with the seating die so as not to crush the shoulder. The case can also balloon slightly when the bullet is seated. The SARCO barrel’s chamber is tight, so I’ve found running the loaded rounds into the resizing die (with the de-capping pin removed, obviously) solves any issue with getting the first round out of the magazine to go into battery. Aside from that, though, reloading is a doddle, and the rounds feed very well out of a good magazine.

.400 CB’s Place in the World

It’s not unreasonable to ask, “OK, why?” Damned if I know. Self-defense? The cartridge’s extra power is unlikely to have a profound effect on ‘stopping power’ over other service cartridges. Hunting? The lack of the ability to get serious velocity out of heavy bullets seriously limits the cartridge in that regard. Competition? Under current rules it holds no advantage over existing cartridges like .40 S&W, which can fit more rounds in the magazine. Small-game hunting? Ought to be grand, but again not better than existing, more readily available options.

Honestly, it just doesn’t stand head-and-shoulders above other, more common calibers in any respect. .357 and 10mm Auto can both use bullets with higher-sectional density which ought to give them an edge in penetration, making them more suited to big game hunting or dangerous game defense. Lighter calibers work fine on small game.

Yes, it ought to be as good as anything out there for self-defense, but there are more practical choices available. Still, it works and I’m having fun, so I guess that’s reason enough.

I’ll be doing chronograph and ballistics testing soon, and we’ll see what’s what. Stay tuned…

Be safe and take care.

Michael Tinker Pearce, 31 May 2021

If you like what you see here, please consider clicking the link above and supporting me on Patreon.

…it’s complicated, because sometimes bigger isn’t really as ‘bigger’ as you might think.

Proponents of the larger calibers point out that a bigger hole does more damage. A bigger hole also means blood pressure drops faster. Seems like a no-brainer, right? But the collected data from actual gunfights doesn’t support this conclusion.

Research in recent years has shown little significant difference in the real-world performance of different calibers between .380 ACP all the way through .44 Magnum when multiple shots are fired. Service calibers (.38 Special, 9x19mm, .357 magnum, .40 S&W, 10mm and .45 ACP) actually perform surprisingly similar shot-for-shot too.. This is baffling; there’s a lot of variation there.

Here’s an experiment that may help explain this: get a thick piece of rubber and shoot it with a .380 ACP and a .45 ACP then look at the holes. The difference between the holes isn’t obvious. That’s because the material is elastic and stretches around the bullet as it passes through, then snaps back. The trick is that human flesh is also elastic and tends to do the same thing.

Regardless of the specific cartridge we’re looking at bullets between .355″ and .451″ in diameter. The difference is 1/10″. That’s not much, and as it turns out it’s not enough to overcome the elasticity of human flesh. Coroners and emergency-room personnel report that they often cannot tell what caliber produced a gunshot wound from a handgun until or unless they find the actual bullet that produced it. This is because flesh is elastic. We’re stretchy.

In other words the ‘hole,’ called the Permanent Wound Cavity, of a .45 ACP isn’t actually significantly larger than the one produced by the .380.

Surprisingly hollow-points don’t change the equation as much as you might expect. Modern hollow-points expand quite a bit, and if you’re relying on blood-loss to stop an attacker the extra damage of a large-bore expanded hollow-point is likely to speed things up slightly. Maybe not enough to make a difference though; an attacker that still has time to kill you isn’t ‘stopped’ in any meaningful sense. Neural Shock from shockwaves transmitted through the body may or may not have an effect, but this seems to be unreliable at best as a stopping mechanism.

The simple truth is that the way you stop an attacker with a handgun (quickly enough to do you any good) is to hit the central nervous system or major elements of the circulatory system, specifically the heart and major arteries. Any bullet that penetrates deeply enough to break the things you need to break can do the job. Any bullet that doesn’t hit these things relies on other methods like gross physical damage to non-vital structures, which is generally a pretty slow way to stop an attacker. In those cases a larger expanding hollow-point bullet is likely to do at least a slightly better job, but that might not be enough to make up for slower follow-up shots.

This may in part be because there are two kinds of ‘stops;’ the Soft Stop and Hard Stop. A Soft Stop (often called a Psychological Stop) occurs when the person consciously or unconsciously, simply gives up or runs away. A Hard Stop (called a Physiological Stop) occurs when an attacker is physically incapable of continuing their attack. A hit in the hand from a .25 Auto can produce a Soft Stop. A hit from a .44 magnum that misses everything immediately relevant can’t produce a Hard Stop. The only way either caliber produces a Hard Stop is to hit the central nervous system, which either caliber can do, or cause catastrophic damage to the circulatory system. An expanded .44 magnum JHP is a lot more likely to cause the latter than a .25 ACP, but .25 isn’t really part of this discussion.

Any bullet that hits the CNS or major elements of the cardio-vascular system is likely to stop someone pretty quickly. In the chaos of a gunfight you are shooting at a relatively small target that you can’t necessarily even see; more chances to hit those targets might be a good idea. Also if the situation is bad enough that you legitimately need to shoot someone you need them to stop as quickly as possible, so being able to put repeated hits on the target as quickly as you can manage is important.

This is why the FBI went back to 9x19mm. It has enough penetration, and recoil is light enough that the average agent can learn to put multiple hits on target fast. On the balance they feel it works better for their needs than a more potent caliber, even if it could be demonstrated that round was significantly more effective. Which, based on the data available, it can’t.

Then there are the variables. The attacker’s physiology; large small, skinny, heavy, fat; these things all make a difference. As does the attacker’s psychology and mental state. How committed are they? What is their goal? An attacker that wants your wallet is going to be a lot easier to achieve a Soft Stop on than one that is absolutely determined to take you down with them. While we’re at it let’s talk about chemicals; are they drunk? Stoned? How much and on what? Is an attacker likely to be in light clothing or bundled up like an Arctic explorer? There’s also movement, environment, barriers, innocent bystanders… the list goes on and on.

So we can all just pack a pocket .380 and call it good? Probably not. For a person living in an urban environment where the principle threat is a full-frontal confrontation with a mugger or perhaps a car-jacking attempt that might well do fine. But someone living in a rural area that might encounter hostile wildlife might reasonably think a 10mm is better suited to their needs. In an apartment building over-penetration is a serious consideration; in a sprawling suburban neighborhood rather less so and in rural environments it could be a non-issue.

I’ve also talked before about the difference between police use of deadly force and civilian needs. The civilian is much less likely to encounter a committed attacker, less likely to need to penetrate barricades or engage in a protracted fight, less likely to have to fight at any significant range and is more likely to have the option of disengaging if circumstances allow. Caliber and weapon selection is different for civilians based on the most likely threats, and there’s a balance each of us has to find based on our individual lives, skills and circumstances.

All this being said ammo selection is not irrelevant; whatever caliber you choose modern, proven defensive ammunition should be employed in whatever caliber you select. Maybe it’s just stacking the odds in your favor, but that’s definitely worth doing when lives are on the line.

I think it is possible that some calibers are somewhat more effective than others, but with all the variables involved, real-life shootings seem to indicate that difference between calibers alone is not decisive. Consider your own physique, skills, abilities, style of dress and circumstances and choose based on that rather than some dubious thought that a given caliber is a better ‘stopper.’

Michael Tinker Pearce, 26 May 2021

If you like what you see here please consider clicking the link above and supporting me on Patreon.

An article on this topic was pointed out to me and I was asked my opinion of the cartridges specified. I started to answer, but thought, ‘Hey, I should do my own version for my blog.’ So here it is. I might add a cartridge or two even.

Mind you I am restricting myself to cartridges that were once popular or were recently introduced but fell flat. There are a host of others that are clearly already obsolete, never attained any real popularity or were never offered in a commercial platform. I’ll be building one of those very soon, so you’ll get to read all about it before too long.

So, in order of diameter…

.25 Auto/ 6.35mm

People like small, clever things. These days it’s electronics, but at the turn of the 20thC. it was pistols.

.22 revolvers had been around since the mid-19th C., but semi-autos were the New Hotness. Sadly .22 LR of the time was not a good choice for tiny autos; no one had any depth of experience adapting it to the platform and a rimmed cartridge in a semi-auto isn’t an intuitive match. John Moses Browning designed a cartridge specifically to fill the role of .22LR in tiny self-loaders, and it worked. By that I mean that tiny guns could be made to function with it. Like the .22LR it was always a marginal prospect for self-defense.

But as time marched on people largely lost interest in micro-pistols, and had learned to make .22 LR work in them for the small market that remained.

Since the GCA68 basically killed the importation of these guns the cartridge has been fading into obscurity. .25 ACP has received no meaningful development since it’s introduction, and while it can be improved on there’s been little impetus to try. Given the millions of guns chambered for it in circulation it’s likely to continue to hang on for a long time, but it is definitely fallen entirely out of relevance.

.32 ACP/ 7.65mm Auto

Famous for equipping a fictional spy and killing a dictator far too late, this was the first wildly successful semi-auto pistol cartridge.

This cartridge has a long and storied history, and was used as a duty weapon well into the 1970’s. It was replaced in service by 9x19mm, not because it wasn’t working but because it was felt to have inadequate penetration against emerging threats.

.32 ACP has two issues: One, it doesn’t quite have the power to make hollow-points both work and penetrate deeply enough for reliable use and two, it only works effectively if you can shoot. Ball ammunition has to be placed precisely to be effective regardless of caliber. and people are convinced that they can substitute diameter for skill. They can’t, but since they almost never have to actually shoot anyone the idea persists.

.32 ACPs final problem is .380 ACP. It has just enough power to make hollow-points work and penetrate deeply enough if you shop around, and you just can’t make a .32 enough smaller than a .380 to justify the perceived lesser effectiveness of the smaller round. Let me be clear- a modern hollow-point bullet that both expands and penetrates adequately is better than ball ammo, but that doesn’t mean non-expanding ammo can’t do the job… if you can shoot.

Like the .25 Auto there are millions and millions of these pistols in circulation, and while ammo is likely to remain available for decades this cartridge’s day has passed.

.32 H&R Magnum

Let’s make one thing perfectly clear from the start. This is a fake magnum that only exists because Harrington & Richardson didn’t want to admit their normal .32s weren’t capable of realizing the full potential of .32 S&W Long without suffering a premature death.

Older reloading manuals show loads that equal or exceed the power of .32 H&R Magnum for .32 S&W Long, but there were a lot of crappy guns sold that wouldn’t hold up to prolonged use with these loads. These .32 S&W Long loads are decent, low-recoil equivalents (in power) of .38 Special, and in a J-frame you get an extra shot. So H&R made the cartridge slightly longer, made a gun as good as it should have been all along and pretended they’d done something new.

It’s hung on by it’s figurative fingernails for decades, but the death-knell was struck when the .327 Magnum came along with 150-200% more power in the same size package. While .32 S&W Long remains a popular caliber for target shooting, small game and even self-defense in the rest of the world it’s popularity has waned in the US. Despite being more recent the .32 H&R Magnum isn’t as popular even in the USA, let alone the rest of the world. Buy one if you like, but be prepared to handload for it, because it’s slipping away.

.357 Sig

At some point it occurred to someone at Sig that they could bottleneck a .40 S&W to .357 and have an equivalent to .38 Super that would fit in a 9mm frame.

Once again it worked pretty much as planned. They overlooked one small thing though. Except for competition shooters in the 1980’s that figured out they could use .38 Super to game the rules of IPSC nobody wanted a .38 Super, and they didn’t want .357 Sig either. More expense, muzzle blast and recoil than 9mm without a demonstrable increase in effectiveness sufficient to justify it.

Various Law Enforcement agencies flirted with it for a time and it has its fans, but essentially it’s dying of apathy. There’s nothing wrong with it really, it’s just that no one cares. It might not vanish from the scene, but it’s well along the path to obscurity.

.40 S&W Auto

No photo for this one… the only .40 S&W I own is a HiPoint I bought for $75, and I’m embarrassed to show you. Just imagine a 9mm; that’s what they all look like anyway.

This cartridge is the answer to a question that would never have been asked if people had better sense, or at least it’s parent cartridge the 10mm Auto was. In the 1980’s the 9mm was perceived as having failed the FBI in the 1986 Miami shootout. It didn’t; tactics, training and doctrine did, but we needn’t go into that here. It was felt it was easier to address caliber than training and culture, and so the 10mm auto was adopted.

Essentially this was a .41 magnum that fit in a Government model or other service-sized handguns. Like .41 Magnum (which we’ll discuss later) it was too much for the job for most people. It’s an excellent cartridge, but it’s recoil demands serious training to master. S&W shortened the 10mm to fit in a 9mm magazine and lowered it’s power to make it easier to train with and a star was born. The FBI and other LE agencies adopted it in droves. It did the job and everyone and their sister Sally was enamored of it. But…

It offered slightly fewer shots than 9mm, with more recoil, greater cost and a steeper training curve without any evidence that it actually worked better… at least not enough better to justify it’s deficiencies. Eventually the FBI threw it under the bus and went back to 9x19mm. Law enforcement agencies followed in droves.

Thing is, it’s a perfectly good caliber, and with the glut of surplus duty guns flooding the market it’s not going away any time soon… but it’s another peg without a hole and it’s likely to fade away in time.

The .41 Magnum

Despite owning the distinction of being nearly the only cartridge that is actually the diameter it claims to be, the .41 magnum was never supposed to be.

In the 1960s hollow-point ammunition was not well developed or particularly reliable, and a bunch of boffins got together and said, ‘wouldn’t it be great to make a gun more effective than a .38 Special with less recoil than a .44 Special or .45 Colt for police duty?’

It wasn’t a bad idea, and they proposed a .41 caliber cartridge that would launch a 200gr LSWC at 900 fps from a duty revolver. Remington agreed, and took up the idea and ran with it… straight down a rabbit hole. They upped the power enough to negate the cartridge’s advantages as a police duty round, but not far enough to really compete with their .44 Magnum. Well played, Remington. Well played.

A few agencies adopted it briefly, but recoil and penetration were excessive and it took dedicated training to master… all to do nothing that .357 magnum wasn’t already doing just fine, thank you.

Again, it’s a great cartridge. It can be loaded light for self-defense, heavy for big game or anything in between; it’s quite versatile. I personally love this cartridge and think it’s wonderful, but while it has always had its fans it never set the world on fire. A lot of younger shooters have never even heard of it. It hangs on as a niche cartridge, developing just enough new fans to keep staggering along. Predictions of it’s demise have been made routinely since the 1970s and it’s still with us. I’m not sure it’s ever going to completely go away.

.45 GAP

At some point it occurred to the folks at Glock that with modern propellants there was no need for .45 ACP to be as long as it is. Consequently if they made it short enough to fit in a 9mm magazine they could easily adapt their existing platforms to it.

It worked just fine. The problem was basically people that wanted a .45 didn’t want a Glock. The operation was a success, but the patient died. Not much more to say about it.

That’s my round-up of cartridges teetering on the brink of the dumpster of history. I hope you enjoyed it and maybe found it educational.

Take care and stay safe.

Michael Tinker Pearce, 15 may 2021.