Monthly Archives: June 2021

Underwood Hero and Extreme Defender 9mm

Two very different approaches to self-defense ammunition from Underwood, both monolithic copper bullets. On the left is the 65gr. Extreme Defender, on the right it their Hero 70gr. Hollow Point.

A while back BBTI got ahold of me and said they had some Underwood ammo left over from their testing. Would I like to do some tests myself? Yes, yes I would thank you! What they very graciously sent me was two boxes each of 9mm Xtreme Defender and 9mm Hero ammunition. Both bullets are light-for-caliber at 65 and 70 grains respectively, and I was eager to try them out.

Light-for-caliber bullets propelled to extreme velocities is an idea that just will not go away. The idea has always been that a light bullet moving very quickly has a lot of energy, and that it will dump that energy rapidly. The thought was that this would cause a physical shock that would incapacitate the target. In reality there just isn’t enough energy there to cause that kind of shock, so the bullet simply under-penetrates badly enough that it can’t reliably reach vital structures. Unless it doesn’t expand, in which case the permanent wound cavity is quite small.

Energy is great, but momentum is your friend when it comes to penetration. Light-for-caliber bullets lack sectional density, which is the ratio of mass to cross section, and penetration is greatly enhanced by having a high sectional density. This is why tanks shoot long, narrow, heavy darts at each other these days. Because physics.

For my test gun I used my Sig-Sauer P6. This has a 3-3/4″ barrel, comparable to many mid-size EDC-style guns. Both of these bullets claim very high velocity for a 9mm, but are not +P rated. I expected that with the shorter barrel velocities would be below the claimed velocity for these cartridges, and I wasn’t wrong. I set up the Caldwell chronograph in front of blocks of Clear Ballistics 10% ordinance gel covered with four layers of denim. All shots were fired from approximately ten feet. Let’s start with the Heros.

Hero or Zero?

The Hero’s hollow-point is big and deep. I had little doubt they would expand spectacularly.

I confess to some doubts about this one. In previous tests light-for-caliber hollow-points usually exhibit spectacular expansion and poor penetration and, spoilers, these were no exception.

Claimed velocity is 1650 fps., which with the 70gr. bullet would yield 423 ft./lbs. of energy. From the P6 they averaged 1569 fps. for 383 ft./lbs. Not bad, and given the shorter barrel of this gun not wildly off.

Bullets expanded to an average of .68 caliber. Impressive!

Rather less impressive was their penetration. The two bullets fired into the gel both penetrated damn near exactly 9 1/2″. In fact bullets fired into bare gel also penetrated about 9-1/2″. Gold Star for consistency, then.

Contrast adjusted to show the permanent wound cavity,

The Permanent Wound Cavity is reasonably impressive, with the bullets expanding immediately and creating a zone of significant disruption about 5″ long, and never fully streamlining. In the track above the bullet came to rest at 90 degrees from the direction of travel.

The FBI specifies a minimum of 12″ of penetration when fired into 10% ordinance gel through four layers of 16oz. denim, and this falls significantly short of that. I consider this a dubious choice for self-defense and would never recommend it for duty ammo. That being said I bet it’s awesome on pests and varmints!

Seriously, what do people have against ‘E’s?

Next came the Xtreme Defender ammunition. These also use a monolithic copper bullet, but they are about as different from a hollow-point as you can imagine. The bullet itself is produced by Lehigh Defense, who makes special purpose ammunition for the armed forces among other things.

As far from a hollow-point as you can get!

The point has been described as being like a flattened Phillips screwdriver tip. The theory is the ogives cut into the bullet combine with the bullet’s rotation to displace tissue. It’s claimed that this produces a hollow-point-like permanent wound cavity, but is barrier-blind to clothing, windows etc. which can seriously affect the performance of conventional ammunition.

The claimed velocity for these bullets is 1700 fps., which produces 417 ft./lbs. of energy. The result I got was an average of 1660 fps. for 398 ft./lbs. Again, given the shorter barrel this isn’t far off at all.

Under-penetration was not an issue for these bullets. The sample went 16″ and was found on the table between the blocks of ballistic gel. It was difficult to get a good photo of this PWC; after several re-castings the Clear Ballistics gel as become Not Very Clear Ballistics gel.

Contrast-enhanced to show the PWC

The damage in the gel is very comparable to hollow-point ammunition. You can see the spiral created by the ogives as the bullet rotated. The bullet maintained a zone of disruption right up to about nine or ten inches, where it appears to have tumbled, then streamlined for the last three or so inches before it exited the gel. The wound track crosses the block at an angle because of me, not because the wound channel curves.

There was effectively no distortion of the bullet. You could reload this one and fire it again.

This bullet appears to have the chops for a self-defense round. Penetration is good but not excessive, and the Permanent Wound Cavity looks good. BUT… This is gel, not flesh, and gel is a comparative media, not a predictive one. Bullets that perform in gel usually, but do not always, perform well in flesh-and-bone targets.

If you want to carry these for self-defense or as a duty round I wouldn’t think you were nuts. All the indications are good and they don’t have excessive penetration, unlike ball ammunition. Plus they perform well against heavy clothing and barriers. In other tests I have seen they maintain an acceptable level of performance even after penetrating windshields, drywall and sheet metal. Personally I’m going to reserve judgement on this one.

The Takeaway

So, two LFC monolithic copper bullets, two different wounding mechanisms, both driven to extreme velocities for their cartridge. The ultra-light hollow-point works like they do; spectacular expansion, poor penetration. Works well against smallish critters, not so much on humans. The other…

Hell, we don’t even have a name for this type of bullet. It’s a very different idea, and it appears to work. It seems to have some advantages over conventional self-defense bullets as well, especially for law enforcement duty. The question is do these qualities carry over into the real world? Time will tell, I suppose.

So, for civilian self-defense and duty the Hero gets a big No. The Xtreme Defender gets a tentative yes; apparently it will at least not work worse than ball, and might work a hell of a lot better. I want more real-world data before firming up that yes.

Shout out to my supporters at Patreon for supplying the Clear Ballistics gel that will replace this murky stuff!

Take care and stay safe.

Michael Tinker Pearce, 10 June 2021

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Here’s a Funny Thought…

Two World Wars! The immortal 1911a1- America’s service pistol for more than seven decades.

We love to debate which caliber is best for a defensive handgun, and that’s been going on ever since practical revolvers became widely available. Endless testing, theories, fashion and ego drive these debates far more than real-world performance in actual gunfights. When such data is collated and presented the studies their results are too often disregarded in favor of cult-of-personality driven opinions, anecdotes cherry-picked to support a personal prejudice and a blatant disregard for factual data.

One of the most famous 20th C. gunfighters used a .38 special. Others used .45s, .357s, etc. A couple of these folks insisted that nothing but their personal choice worked worth a damn, yet somehow these fellows all survived multiple gunfights and came out on top regardless of their caliber-of-choice, weapon or the success of other contemporary gunfighters that made different choices.

These men were very often less well-armed than those they faced. Care to guess why they prevailed regardless?

A Dirty Little Secret…

When I served in the army in the early 1980s we used 1911a1 pistols, most of them still composed of WW2 leftovers. They were pretty sad and worn out. We did not think particularly well of them, but guess what? Nobody really cared. They worked well enough and in the grand scheme of things they were so unlikely to ever be used that no one fussed about them. We had much, much bigger problems.

Yes, the 1911a1 served for 70+ years, but this wasn’t because they were the best of all possible pistols. It was because it was going to be a huge, expensive pain in the ass to replace them and pistols just didn’t matter enough to be bothered until we had to replace them. The 1911a1s were worn out, we were running out of spare parts and we had a treaty obligation to standardize the 9x19mm that we couldn’t put off indefinitely.

The 1911a1 is an ingenious design and one of the all-time greats among service pistols. In updated form it’s still an excellent tool. But a military service pistol is literally the least important weapon system in the arsenal of any military force. Today there are lighter, more capable, more versatile, cheaper and more reliable platforms for that use.

…But We’re Not The Army

OK, some of you are, but most of us are civilians, and rather than an almost irrelevant last-ditch ‘Hail Mary’ a handgun is often our first line of defense as individuals or law enforcement. Our choice of weapon, caliber etc. is significantly more important. Yes, the odds that you will need a gun are pretty small, but if you do need it you will need it very badly indeed. You need an effective weapon that you are comfortable with and shoot well. So which caliber should you choose?

Availability, power, fast follow-up shots, platform and how much you enjoy shooting it all come in to play in caliber selection. Hint- if you don’t enjoy shooting it or cannot find/afford it you won’t practice

I think that it is possible, even likely, that all things being equal some service calibers may be objectively better than others. The problem is all things are never equal; there are a huge number of variables in a gun fight. Motivation, determination, skill, training, lighting conditions, clothing, numbers of opponents… the list goes on and on. Among the variables involved in a gunfight the caliber of your weapon may be one of the least important factors.

For us civilians the sole and only purpose of a gunfight is to make the other guy stop whatever he’s doing that makes it necessary to shoot him… and preferably survive, of course. With all the variables in play it’s not impossible that your choice of weapon or caliber will play a critical role, but it’s not likely to be a decider unless you choose very stupidly indeed.

There are a lot of very good guns out there in calibers that, in real life, all seem to work about as well as each other. Pick what works for you; a weapon you’ll actually have with you, a gun that is reliable and that you shoot well. Learn the gun and it’s manual of arms inside and out. Importantly you need to pick a caliber you will actually practice with. If you don’t reload your own ammo that means something commonly available. OK, obviously at this moment none of them are easily available, but that will change. Knock on wood.

Then, when all is said and done, remember that guns don’t win gunfights. People do. Setting aside luck, how do they do it?

Stop me if you’ve heard this one…

You Are the Weapon, the Gun is Just a Tool

Understanding the gun is only the beginning; you need to understand your primary weapon; know your own strengths, weaknesses and limitations. Have a realistic appraisal of your abelites, or what you can and can’t do with your weapon of choice. Plan to work around those limitations.

We all have very different lives and circumstances. Some of us can carry a full-size service pistol in our daily lives. Some of us can only manage to carry a very small pistol. That’s fine; carry the best tool you can that’s compatible with your needs and situation. Plan to minimize the effect of weaknesses and maximize your strengths.

If you know you can’t deploy your weapon quickly don’t try; instead focus on how to create opportunities where speed will not be a deciding factor. If you know you shoot poorly past a given range think about how you might get within that range in a variety of scenarios. Understand what you’ve got and what you can do, then plan accordingly.

Yep. Tactics, Training and Doctrine. If they’re bad you’ll probably lose. If they’re good you have a much better chance of making it through.

There’s a reason that modern, polymer-framed 9mms have become so popular, and it’s not just fashion. They are light, compact, reliable and hold a lot of bullets. In purely practical terms, what’s not to like?

But What if That’s Not Enough?

Then it’s not enough. Look, there are situations where you just aren’t going to win, and anyone that tells you otherwise is trying to sell you something. A drunk driver plows into your café. A brick falls on your head. You get hit by lightning. Or maybe there’s just too many of them. Sometimes excrement occurs, and all your training and planning just isn’t enough. Get over it. There are things we can control and things we can’t… but chance favors the prepared mind, and having a plan is always better than not having one. Even if the plan goes sideways.


There’s a saying in certain circles, “If you ain’t cheatin’ you ain’t tryin.’ By all means cheat if you can, and do whatever you reasonably can to stack the odds in your favor. This isn’t a game; ‘playing fair’ is not only not required, it’s stupid. Another old saying is that, ‘A man that finds himself in a fair fight has made a serious error in judgement.’ Plan on how to not find yourself in that fight. Be aware of your surroundings, keep an eye on suspicious persons or activities. Try to see the fight coming so you can, if possible, get out of it’s way. Failing that seeing it coming gives you the best chance to be prepared.

The advice often given is to carry the largest, most powerful gun you reasonably can. Given the caveat that ‘reasonably can‘ includes being able to use it effectively it’s not bad advice. After all why wouldn’t you stack the odds? It’s life or death; you’d be a fool not to.

Same thing with modern defensive ammunition. Sure, if you do your part even ball will probably do the job, but if using good hollow-points will increase the odds in your favor, even a little, then you definitely should use them. Provided that they are suitable to your weapon of choice and it functions with them, of course. Every bit helps and any advantage is worth employing if it’s practical to do so.

Stop Worrying About Caliber

Anything in the range of ‘service calibers’ will do the job if you do yours. For civilian self-defense that means anything between .380 ACP and .45 ACP. Find what works for you and your life, then train with it. Learn as much as you can, think it through and decide what the best choice or choices are for you and your own unique circumstances. Be aware of the compromises imposed by your choices and incorporate them into your personal plans. Because that’s what going to keep you alive if anything can.

Michael Tinker Pearce, 10 June 2021

.400 Cor Bon: The Little 10mm That Could, But Didn’t

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.

AMT’s double-action backup, famous for it’s brutal recoil, was offered in .400 Cor Bon. That must have been, uh, ‘exciting’ to fire!

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.

My 1911a1 Donor Gun, a Frankengun assembled from a Sytema Colt lower and a GI Surplus upper. A dear friend assembled it years ago and eventually gave it to me as a gift. It’s always been reliable, accurate and an excellent shooter.

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…

Accuracy was, uh, ‘sub-optimal.’

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:

Not at all a good 7-yard rapid-fire group.

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

OK, that’s not right…

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?

Five shots in five seconds with the Gold Dot bullets , everything went just fine.

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.


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

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