Ballistics by the inch

Welcome!

As noted there to the right, this blog is intended to be a discussion forum primarily concerned with the ‘nuts & bolts’ of how we did our testing and the results we obtained, not a general gun discussion forum.  As such, you’ll find a number of posts already created pertaining to each of the different calibers, as well as some general topics – just go to the appropriate entry and pose a question or comment, then you can follow the discussion either by visiting the blog or subscribing to the RSS feed.  If a discussion thread gets too long, or takes a turn which warrants further attention on its own, we’ll create a new post and shift things over to it.

We reserve the right to moderate comments – to keep them on-topic, and to keep things ‘family friendly’ – but will take a fairly light hand insofar as possible.  Your cooperation on this is appreciated.

If you need to contact any of us directly, you can do so via this email address:

Jim Downey: jimd@ballisticsbytheinch.com

So, welcome – and jump in!

November 10, 2008 Posted by | Uncategorized | Comments Off on Welcome!

Effective shotgun ranges.

One of the questions we get regularly is asking whether we’re going to do some velocity/chop tests on shotguns. For a variety of reasons (both logistical & legal) we’ve decided that such tests are beyond the scope of what we want to tackle.

But that doesn’t mean that it’s not something of interest to us, collectively and individually. I’ve previously posted about tests which John Ervin at Brassfetcher has conducted showing the effectiveness of buckshot at 50 yards. And from personal experience, I knew that slugs from a 12 gauge are effective for hunting (or self defense) out to 100 yards, depending on the skill of the shooter.

But how about slugs at 200 yards? And how about DIY ‘cut shells’, which mimic slugs? And, say, if you did happen to hit a target at 100 yards with buckshot, would it be lethal?

Via The Firearm Blog, this video explores all these questions, and provides some VERY interesting answers:

It’s well worth the time to watch the whole thing. But the bottom line is that 00 Buckshot pellets would still be lethal at 100 yards, if you could connect with your target. And slugs? Easily to 200 yards, with a fair amount of control on hitting your target. At 300 yards, they’re still effective, but the trajectory is such that it’s much more difficult to reliably hit the target. And at 400 yards … well, watch to video to see for yourself.

Kudos to Iraqveteran8888 for conducting some really solid and informative tests, and sharing that information with the public.

 

Jim Downey

July 16, 2016 Posted by | Anecdotes, Data, Discussion., Links, Shotgun ballistics | , , , , , , , , , , , , , , , , , , , | Leave a comment

Security on a budget.

If you’ve got a couple thousand dollars available, it’s relatively easy to select one or more firearms for home defense, or for your bug-out bag, or what have you. You’ve got plenty of choices, and just need to sort through the options available and find the gun(s) which best fit your needs.

But what if you only have a couple hundred bucks?

A good used pump shotgun will serve most people pretty well for home defense. But what if you want something more compact for your bug-out bag or emergency kit? Then your options are much more limited, and you have to prioritize. You have to decide just what you want your firearm to be able to do, and then see what is available to best meet those goals.

This is one such solution. By no means do I think that it is the only solution. But how I went through the decision-making process and then how I put it into practice might provide some insights.

I wanted a fairly versatile firearm for an emergency kit, the sort of thing which could get taken along on a long drive, or to have when vacationing away from home. I wasn’t thinking of the firearm as a combat weapon, but something which would be suitable for emergency hunting or self-defense. I wanted it to be compact, reliable, and with a wide enough selection of loadings* (whether factory or my own reloads) to meet a range of uses from hunting small game to protecting against large predators.

After thinking it over, I decided to look for a good used .357 magnum revolver, with a 3 – 5″ barrel. I didn’t already have such a handgun, so it would also give me a chance to fill in a gap in my collection. After some shopping around, I found a 40 year-old Ruger Security Six with a 4″ barrel in my price range. The gun looked and felt mechanically sound, but was kinda beat-up. There was a fair amount of holster wear on the bluing. The walnut grips had been abused, with scratches and part of the bottom finger groove broken away. The bore looked fine, but there was a lot of built-up lead around the forcing cone, and the trigger and cylinder barely moved from what felt like built-up gunk.

I decided to take a chance, and brought it home. Yesterday I had the time to take it apart and completely rework it. What I found was that while the gun had been reasonably well cared-for, seemingly no one had ever bothered to do more than just a basic quick cleaning. I pried out/off about a 1/16″ layer of accumulated dirt, burnt powder residue, and old oil from most of the internal surfaces, particularly around the trigger assembly. Little wonder it felt almost frozen in place. I went ahead and did a thorough cleaning of the rest of the gun, and was even able to remove the lead deposits with minimal work.

The grips were first slightly reconfigured with a wood file then sanded thoroughly. I refinished them to a satin finish for slightly better tactile control.

Here’s how the gun looks now:

20160605_070704

20160605_070724

It’s not gorgeous. It could certainly stand to be reblued, or at least have the bluing touched-up. But I’m not going to worry about it — for my needs, it’s just fine as it is now.

The moral of the story is to think through what you want your firearm to do, then do your research to see what the range of choices are. Shop around. If you have modest skills with hand tools, you should be able to make dramatic improvements in the performance & appearance of a gun (perhaps with some help from online videos and instruction).

Good luck!

 

Jim Downey

*Ammo Selection I will keep on hand for this gun in the emergency kit (representative examples):

 

 

June 5, 2016 Posted by | .357 Magnum, Discussion., Revolver | , , , , , , , , , , , , , , , , , , | Leave a comment

An absurd comparison. Or is it?

We had another of those wonderful & rare mid-50s January days here today, so I decided to get out for a little range time.

In addition to the other shooting I did (basically, practice with some of my preferred CCW guns), I also did a little head-to-head comparison between a Smith & Wesson M&P 360 J-frame in .38 Special and a Colt Anaconda in .44 Magnum.

Wait … what? Why on Earth would anyone even consider trying to do such an absurd comparison? The S&W is a very small gun, and weighs just 13.3 ounces. The Anaconda is a monster, weighing in at 53 ounces (with the 6″ barrel that mine has), and is literally twice as long and high as the J-frame. The .38 Special is generally considered a sufficient but low-power cartridge for self defense, while the .44 Magnum still holds a place in the popular mind as ‘the most powerful handgun in the world‘ (even though it isn’t).

Well, I was curious about the perceived recoil between the two, shooting my preferred loads for each. The topic had come up in chatting with a friend recently, and I thought I would do a little informal test, just to see what I thought.

So for the M&P 360 I shot the Buffalo Bore .38 special +P, 158 gr. LSWHC-GC which I have chrono’d out of this gun at 1050 fps, with a ME of 386 ft-lbs.

And for the Anaconda I shot Hornady .44 Remington Magnum 240gr XTP JHP, which I have chrono’d at 1376 fps, with a ME of 1009 ft-lbs. (Actually, I don’t have a ‘preferred carry ammo’ for this gun, but this is typical of what I shoot out of it. Were I going to use it as a bear-defense gun, I’d load it with this.)

My conclusion? That the M&P 360 was worse, in terms of perceived recoil. In fact, I’d say that it was *much* worse.

It’s completely subjective, but it does make sense, for a couple of reasons.

First, look at the weight of each gun, compared to the ME of the bullets shot. The J-frame is 13.3 ounces, or about 25% of the 53 ounce weight of the Anaconda. But the ME of 386 ft-lbs of the .38 Special bullet is 38.25% of the ME of the .44 Mag at 1009 ft-lbs. Put another way, the J-frame has to deal with 29 ft-lbs of energy per ounce of the gun, where the Anaconda has just 19 ft-lbs of energy per ounce of the gun. That’s a big difference.

Also, all that recoil of the J-frame is concentrated into a much smaller grip, when compared to the relatively large grip of the Anaconda. Simply, it the difference between being smacked with a hammer and a bag of sand, in terms of how it feels to your (or at least, my) hand.

Thoughts?

 

Jim Downey

January 31, 2016 Posted by | .38 Special, .44 Magnum, Anecdotes, Discussion. | , , , , , , , , , , , , , , , , , | 4 Comments

Dealing with power, part II: Recoil.

Yesterday I took advantage of the unseasonable warmth to get out to the range and have a bit of fun & practice:

Cans

Yeah, those cans jump pretty good when popped with .45 Super rounds, particularly out of my Cx4 Storm.

Which, this time out, was a lot more fun to shoot than when I last took it out. Because I had gotten around to adding a slip-on recoil pad to it. Specifically, one of these: Pachmayr Decelerator® Slip-On Recoil Pads (Not a paid ad, and I got mine from a different seller.)

Because while you want to take steps to manage the power of a round like the .45 Super on the INSIDE of your firearm, you also have to take steps to manage the recoil you experience on your body. Or you’ll avoid practicing. Or will develop bad habits (flinching, grimacing & closing your eyes, etc). Or you’ll be spending money on painkillers, bruise ointments, and massages that you can more profitably spend on ammo/components.

While I like the overall design and ergonomics of the Cx4, the thin rubber ‘recoil pad’ it comes with doesn’t actually do much to tame the recoil, particularly out of .45 Super rounds. So I spent some time looking over different products to help with that, and settled on the Decelerator. Here’s how it looks on my gun:

Left

And:

Right

I was really pleased with the difference it made. Easily knocked off at least half of the felt recoil. Probably more like 3/4ths. And the added lengthening of the stock isn’t at all a problem for me with my long arms.

And of course, if one of my friends wants to prove how macho/masochistic they are, it’ll slip right off …😉

However you do it, take into consideration how best to manage recoil in your firearms. I’m not recoil-shy. Never have been. But it just makes sense to be kind to your body over the long haul.

 

Jim Downey

PS: the optic is a Vortex Venom holographic red dot sight. So far, I really like it.

December 23, 2015 Posted by | .45 Super, Discussion. | , , , , , , , , , , , , , , , | 1 Comment

Four .380 CCW guns compared.

Had a chance to get out in the cool and do some head-to-head comparisons of four different .380 ACP pistols. Here they are:

All 4

From left to right: Remington RM380, Rohrbaugh R380, Glock 42, and Sig Sauer P238.

I’m going to discuss the RM380 and the R380 together, since the first is the latest version of the latter. See, Rohrbaugh was sold to Remington about a year ago, and shortly thereafter Remington began to tweak the design of the R380 a bit, which I think was mostly an improvement.

The original Rohrbaugh was designed to be the perfect pocket pistol, with smooth edges in a *very* compact yet ergonomically-friendly package. And as my original review indicates, I thought it was a great gun.

RM380

The new RM380 is essentially the same design. They’ve changed the mag release from the European-style butt plate to a conventional side-button. They’ve given the grips more texture which make it easier to hold onto (many people who owned a Rohrbaugh added either a slip-on grip or some grip tape to accomplish the same thing). And they’ve added a slight beaver-tail to help keep the external DA hammer from pinching the web of the hand. They’ve made it so the slide locks back after the last round in the mag is fired. And they’ve made an additional magazine with a small extension which makes it even easier to shoot the gun. In my opinion, these are all improvements.

Changes which aren’t improvements? Well, the gun is lighter, at about 12.2 ounces (the Rohrbaugh was 13.5), and that contributed to increased felt recoil. The fit & finish are not nearly as nice as the R380. But then again, the Remington now costs about 1/3 what the original Rohrbaugh did.

Both guns have very basic sights. They are not guns to take to a competition at 25 yards. But both of them would pop 6″ spinners consistently at 7 yards. Both operated reliably, though I was just using hardball ammo — you’d want to select your preferred SD load and make sure that it shot out of your gun consistently and reliably.

The trigger on the Remington was still a VERY long pull. First time I shot it, I thought it was even worse than the Rohrbaugh in that regard. But after going back and forth between the two, I think it just felt longer, because in addition to being long it was fairly gritty and rough. That might clean up over time (this gun had less than 100 rounds through it), but it was noticeably worse than the Rohrbaugh.

I’ve done a brief review of the Glock 42 previously. What I said then still stands:

Comments: I did not expect to like this gun. I was REALLY surprised when I did. Seriously, it is the best-shooting Glock I’ve ever handled. For such a small gun, it fit my large hands comfortably and was easy to shoot well. With Glock quality and reliability, this may be the first .380acp I would seriously consider as a CCW gun.

I had done a previous review of the P238 with the classic 1911-style grips, which can be found here. This one was brand-new … literally, it had just been picked up at the store and then brought out to the range. And it has the Hogue-style grips and the finger extension on the mag, which I really liked.

Sig 238

The large front fiber optic sight made target acquisition fast and easy. The grips fit my large hands very well, and made it easy to shoot the gun accurately.

So, how did the four guns feel, shooting them head-to-head?

Jim and Sig

OK, a couple of notes first. We shot Remington UMC 95gr hardball ammo. We loaded up 6 rounds into each mag, then shot first one gun, then another, then another, then another. We mixed up the order of which followed which. And we shot at both 7 yards and 10 yards.

My personal preference for shooting? This order, with notes:

  1. Sig P238. Had the least perceived recoil and greatest accuracy. For fast, multiple hits it was great, getting back on target with minimal fuss. Very crisp and clean trigger.
  2. Glock 42. Slight sting from the recoil, accuracy almost as good as the Sig. Again, getting back on target was fast and easy. Trigger not as good as the Sig, but familiar to anyone who knows how any other Glock shoots.
  3. Remington RM380. The worst recoil of all four guns, but the improvements to the grips and the mag extension really make a difference for accuracy. The long, rough trigger almost moved this to #4.
  4. Rohrbaugh R380. The least accurate and the most difficult to get back on target for follow-up shots.

Now, I want to stress that all four guns were adequately accurate at 7 yards. Shooting fast, I could get at least 5 out of 6 within about a 12″ circle, and hit at least one or two hits on a 6″ spinner. Consistently. Since I don’t own any of these guns, I would expect that I could improve on that with practice. Of course, most Self Defense ammo is usually hotter, and would present more of a problem for recoil and target re-acquisition. But I still think all four guns would perform well.

That’s how I would rank the guns for shooting. But that isn’t the only factor in considering a gun for concealed-carry.

As I noted in my review, I don’t like having a “cocked & locked” pistol in my pocket. And if I’m going to have a CCW weapon in a holster, then I might as well step up to a full 9mm as opposed to a .380. So that’s a big strike against the P238 in my book, as nice a gun as I actually found it to be.

It also depends on exactly what you want out of your minimal CCW gun. Do you want the lightest? The thinnest? The smoothest? Or does shoot-ability matter more?

It’s a matter of personal preference. I think that I would rank my selection for concealed carry this way, with some brief explanation for each:

  1. Remington RM380. A really good choice for a light, thin, pocket pistol intended to be used as either a back-up or deep cover gun. But I’d spend some time working on smoothing out that trigger.
  2. Glock 42. Not as small or as light as the RM380. But much better sights, and a most stable platform in my hands. Meaning that I would consider it as a primary CCW, not just as a back-up.
  3. Rohrbaugh R380. Weighs about what the Glock does, but is the smallest/thinnest of all four.
  4. Sig P238. A great shooter. And if you’re willing to carry it cocked & locked in your pocket, then I can easily see how this could be anyone’s first choice. But for me, I’d want it in a belt holster (or shoulder rig), and that’s a big disadvantage — I might as well carry a much more powerful gun.

But hey, that’s just my calculation. Feel free to weigh in with your own.

 

Jim Downey

 

December 17, 2015 Posted by | .380 ACP, Discussion. | , , , , , , , , , , , , , , , | 3 Comments

‘Rifleshooter’ does .223/5.56 chop tests down to 6″

A very nice companion to our .223 chop tests:

223 Remington/5.56mm NATO Barrel length versus Velocity- Short Barrels- 6 to 14 inches

In 223 Remington/5.56 NATO, velocity versus barrel length: A man, his chop box and his friend’s rifle, we cut the barrel of a factory Remington 700 chambered in 223 Remington back one inch at a time and recorded the average velocity for four different 223 Remington and 5.56mm NATO cartridges.  The data set generated from that post provided imperial values for muzzle velocities from 26″ to 16.5″.  A few readers suggested mounting the barrel in a pistol and continuing the test for shorter barrels- we liked the idea.  In this experiment, we gathered data using the same barrel from the first 223 Remington/5.56mm NATO experiment (on a pistol action), with the same four kinds of ammunition from 14″ to 6″.

 

Good protocols, good documentation, good data. And between his different tests, he covers a wider range of barrel lengths than we did, and has some different loadings — so what’s not to like? Go check it out, and bookmark it to share with others!

 

Jim Downey

November 29, 2015 Posted by | .223, Data | , , , , , , , , , , | 1 Comment

Lucky seven.

Thanksgiving weekend 2008, we launched the BBTI website and blog. So while the 28th is the actual anniversary, I tend to think of the start of this journey on Thanksgiving each year.

Seven years. Wow.

And in that time so much has changed. As I’ve noted previously, BBTI has become a standard reference world-wide, and I think that we’ve actually helped create some changes in how ammo manufacturers market their products, providing customers with more reliable & useful information.

But there’s so much more which has come about because of BBTI. I’ve met and made friends with a lot of people. I’ve had interesting discussions & correspondence and learned an incredible amount from people who are much more knowledgeable than I am. People from almost every walk of life, and from all around the world. It’s been fascinating.

In my traditional year-end review I’ll get into all the numbers, but it has been a very good year in terms of visitors to the BBTI page and this blog. So for now I’ll just repeat what I said last year:

Thanks to all who have cited us, written about us, told their friends about us. Thanks to all who have taken the time to write with questions and suggestions. And thanks to all who have donated to help offset the ongoing costs of hosting and testing — it makes a difference, and is appreciated.

Cheers!

 

Jim Downey

November 26, 2015 Posted by | Data, Discussion. | , , , , , , , , | Leave a comment

Velocity is great, but mass penetrates.

OK, kiddies, it’s time for SCIENCE!

Ballistic science, specifically. I promise to keep the math to a minimum, because I don’t like it much, either. Jim Kasper is the one who thinks in terms of equations, not me.

If you look at any of the various pages for test results on BBTI you will see that each caliber/cartridge also has a link for a Muzzle Energy (the kinetic energy of a bullet as it leaves the muzzle of a gun) graph for that set of results. That’s because Muzzle Energy can also give an idea of the effectiveness of a given ammo, since it is a calculation of both the weight of a bullet as well as the velocity it is traveling. This calculation, specifically:

E_\text{k} =\tfrac{1}{2} mv^2

Here’s what that says in English, taken from the explanation that goes with that image on Wikipedia:

The kinetic energy is equal to 1/2 the product of the mass and the square of the speed.

In other words, you multiply the weight of the bullet times the square of the velocity, then take half of whatever number you get. And that gives you the Muzzle Energy, usually (as on our site) expressed in foot-pounds of energy.

So there are two ways you can change the result: change the amount of weight, or change the amount of velocity.

But since it is the square of the velocity (the velocity times itself), changes to the velocity have a larger impact on the final amount of Muzzle Energy. That’s the reason why how the velocity changes due to barrel length is such a big deal, and why we’ve done all the research that we’ve done over the last seven years.

But while Muzzle Energy gives you a good way to compare the power and potential effectiveness of a given cartridge as a self-defense round, there are a couple of other factors to consider. A couple of VERY important factors.

One is the shape and composition of the bullet itself. There’s a very good (surprisingly good, in fact — I heartily recommend you read the whole thing) discussion of the basic shapes and how they interact with the human body in this online teaching tool intended for medical students. The relevant excerpt:

Designing a bullet for efficient transfer of energy to a particular target is not straightforward, for targets differ. To penetrate the thick hide and tough bone of an elephant, the bullet must be pointed, of small diameter, and durable enough to resist disintegration. However, such a bullet would penetrate most human tissues like a spear, doing little more damage than a knife wound. A bullet designed to damage human tissues would need some sort of “brakes” so that all the KE was transmitted to the target.

It is easier to design features that aid deceleration of a larger, slower moving bullet in tissues than a small, high velocity bullet. Such measures include shape modifications like round (round nose), flattened (wadcutter), or cupped (hollowpoint) bullet nose. Round nose bullets provide the least braking, are usually jacketed, and are useful mostly in low velocity handguns. The wadcutter design provides the most braking from shape alone, is not jacketed, and is used in low velocity handguns (often for target practice). A semi-wadcutter design is intermediate between the round nose and wadcutter and is useful at medium velocity. Hollowpoint bullet design facilitates turning the bullet “inside out” and flattening the front, referred to as “expansion.” Expansion reliably occurs only at velocities exceeding 1200 fps, so is suited only to the highest velocity handguns.

Now, while that last bit about needing to exceed 1200 fps may have been true, or a ‘good enough’ approximation a few years ago, it isn’t entirely true today. There has been a significant improvement in bullet design in the last two decades (and these innovations continue at a rapid pace), so that there are now plenty of handgun loads available which will reliably expand as intended in the velocity range expected from the round.

The other REALLY important consideration in bullet effectiveness is penetration. This is so important, in fact, that it is the major criteria used by the FBI and others in assessing performance. From Wikipedia:

According to Dr. Martin Fackler and the International Wound Ballistics Association (IWBA), between 12.5 and 14 inches (318 and 356 mm) of penetration in calibrated tissue simulant is optimal performance for a bullet which is meant to be used defensively, against a human adversary. They also believe that penetration is one of the most important factors when choosing a bullet (and that the number one factor is shot placement). If the bullet penetrates less than their guidelines, it is inadequate, and if it penetrates more, it is still satisfactory though not optimal. The FBI’s penetration requirement is very similar at 12 to 18 inches (305 to 457 mm).

A penetration depth of 12.5 to 14 inches (318 and 356 mm) may seem excessive, but a bullet sheds velocity—and crushes a narrower hole—as it penetrates deeper, while losing velocity, so the bullet might be crushing a very small amount of tissue (simulating an “ice pick” injury) during its last two or three inches of travel, giving only between 9.5 and 12 inches of effective wide-area penetration.

As noted above, the design of the bullet can have a substantial effect on how well it penetrates. But another big factor is the weight, or mass, of the bullet relative to its cross-section — this is called ‘sectional density‘. Simply put, a bullet with a large cross-section and high mass will penetrate more than a bullet with the same cross-section but low mass moving at the same speed. It isn’t penetration, but think of how hard a baseball hits versus a whiffleball moving at the same speed. They’re basically the same size, but the mass is what makes a big difference. (See also ‘ballistic coefficient‘).

With me so far?

OK, let’s go all the way back up to the top where I discussed Muzzle Energy. See the equation? Right. Let’s use the baseball/whiffleball analogy again. Let’s say that the baseball weighs 5.0 ounces, which is 2,187.5 grains. And the whiffleball weighs 2/3 of an ounce, or 291.8 grains. A pitcher can throw either ball at say 60 mph, which is 88 fps. That means (using this calculator) that the Kinetic Energy of a baseball when it leaves the pitcher’s hand is  37 foot-pounds, and the whiffleball is just 5 foot-pounds. Got that?

But let’s say that because it is so light, the pitcher can throw the wiffleball twice as fast as he can throw a baseball. That now boosts the Kinetic Energy of the whiffleball to 20 foot-pounds.

And if you triple the velocity of the whiffleball? That gives it a Kinetic Energy of 45 foot-pounds. Yeah, more than the baseball traveling at 88 fps.

OK then.

Now let’s go look at our most recent .45 ACP tests. And in particular, the Muzzle Energy graph for those tests:

What is the top line on that graph? Yeah, Liberty Civil Defense +P 78 gr JHP.  It has almost 861 foot-pounds of energy, which is more than any other round included in those tests. By the Muzzle Energy measure, this is clearly the superior round.

But would it penetrate enough?

Maybe. Brass Fetcher doesn’t list the Liberty Civil Defense +P 78 gr JHP. But they did test a 90 gr RBCD round, which penetrated to 12.0″ and only expanded by 0.269 square inch. Compare that to the other bullets listed on his page, and you’ll see that while the depth of penetration isn’t too bad when compared to other, heavier, bullets, that round is tied with one other for the least amount of expansion.

Driving a lightweight bullet much, much faster makes the Muzzle Energy look very impressive. Just the velocity of the Liberty Civil Defense +P 78 gr JHP is impressive — 1865 fps out of a 5″ barrel is at least 50% faster than any other round on our test results page, and almost 400 fps faster than even the hottest of the .45 Super loads tested.

But how well would it actually penetrate? Without formally testing it, we can’t say for sure. But I am skeptical. I’m not going to volunteer to getting shot with one of the things (or even hit with a whiffleball traveling 180 mph), but I’m also not going to rely on it to work as it has to in the real world, where deep penetration is critical. I want a bullet with enough punch to get through a light barrier, if necessary. Like this video from Hickok45, via The Firearm Blog:

Personally, I prefer a heavier bullet. Ideally, I want one which is also going to have a fair amount of velocity behind it (which is why I have adapted my .45s to handle the .45 Super). All things being equal (sectional density, bullet configuration and composition), velocity is great, but mass is what penetrates.

Jim Downey

November 8, 2015 Posted by | .45 ACP, Data, Discussion. | , , , , , , , , , , , , , , , , , , , , , , , , , , , | 3 Comments

Dealing with power.

About 40 years ago, when I was an idiot teenager (yeah, I know — redundant, particularly in my case), we got this ’48 Willys Jeep. Since the engine was shot, we dropped an Olds V-6 in it. This was, essentially, like strapping a rocket to a skateboard. And it was too much power for idiot teenage me to handle.  Twice I snapped the driveshaft on the thing, just dumping the clutch too damned quickly. Twice. My uncle (who I lived with) was certain that I had been racing or something similar. The truth was, I didn’t even have that much of an excuse; I had simply goosed the engine too much and popped it into gear too fast. The original driveshaft just couldn’t handle that much of a power spike.

This is kinda what happens to your poor .45 ACP firearm when you decide to run some .45 Super through it.

With the Jeep, we wound up putting a more robust driveshaft in it. And I learned that if I wanted to keep driving it, I needed to be less of an idiot.

This analogy holds to how you should approach handling .45 Super power out of your .45 ACP gun. Chances are, very occasional use of these much more powerful loads won’t cause any problem in a quality, modern-made firearm. But if you’re smart, you’ll either greatly limit how many times you subject your gun (and your body) to that amount of power, or you will take steps to help manage it better and extend the life of your gun.

Typical ‘standard’ (non +P) .45 ACP loads tend to have a maximum pressure of between say 15,000 PSI and about 18,000 PSI. When you get past that, you get into ‘over-pressure’, or +P territory, up to about 23,000 PSI. This is the range most common modern firearms are built to handle safely.

But .45 Super generates more chamber pressure than that. How much more? Well, it’s a bit difficult to say, since there is a surprising dearth of data readily available. Neither my 49th Edition of Lyman’s Reloading Handbook nor my 13th Edition of Cartridges of the World have data for the .45 Super. Real Guns has some reloading formulas for .45 Super which give results consistent with our tests, but there are no pressure specs listed. Hodgdon Reloading has some pressure specs (in C.U.P.), but all their listed results for .45 Super are well below what our tests results were. Wikipedia lists .45 Super as having a maximum pressure of 28,000 PSI, and given that .460 Rowland is usually considered to run 35,000 – 40,000 PSI, that is probably in the correct ballpark.

I have written previously about converting a standard Glock 21 from .45 ACP over to .460 Rowland, and what is involved with that. Specifically, a new longer barrel with a fully-supported chamber which accommodates the longer case of the .460 Rowland, a 23 pound recoil spring, and a nice compensator to help tame the recoil. I also changed out the magazine springs, using an aftermarket product which increases the spring power by about 10%. This is because even with the other changes, the slide still moves much faster than with .45 ACP loads, and the increased mag spring power helps with reliability in feeding ammo. But even with all of that, shooting full-power .460 Rowland loads tends to cause damage to my magazines (as seen in the linked post).

Do you need to do all that in order for your firearm to handle frequent use of .45 Super loads? Well, I think that if you want to use a .460 Rowland conversion kit, it *will* tame the amount of recoil more than enough, but I don’t think that it is necessary to go quite that far. I should note that I have now run several hundred .45 Super loads through my Glock 21, and the gun has operated flawlessly — WITHOUT any damage to the magazines.

Converted G21 on left, G30S on right.

Converted G21 on left, G30S on right.

Rather, I think that the smart thing to do is to start off with going to a heavier recoil spring, perhaps swapping out a metal guide rod for a plastic one (if your gun comes with a plastic guide rod). Stronger magazine springs are probably still a good idea, to aid with reliable feeding. If suitable for your gun, add in a recoil buffer. These are the steps I have taken with my Glock 30S, and am planning for my Beretta Cx4 Storm. So far I have put a couple hundred .45 Super loads through the G30S with this configuration, and it has operated without a problem — again without any damage to the magazines.

As I said in my previous blog post, I still think that the .460 Rowland is a hell of a cartridge. But I think that the .45 Super offers almost as many advantages to the average shooter, with less hassle. I would still recommend that anyone who intends on shooting more than the very occasional .45 Super loads out of their gun consider making some simple changes to handle the additional power and extend the life of their gun. Don’t be like the idiot teenage me; deal with the power intelligently.

 

Jim Downey

 

 

November 1, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, .460 Rowland, Data, Discussion., Links | , , , , , , , , , , , , , , , , , , , , , | 4 Comments

.45 Super data now published.

At long last, we’ve now put up the page with the results of our .45 Super/.450 SMC tests earlier this year! We’ve also published the additional .45 ACP rounds tested at the same time, which doubles the amount of data for that cartridge available on our site.

As noted on the new .45 Super page:

.45 Super and .450 SMC (Short Magnum Cartridge) are two relatively recent variations on the classic .45 ACP cartridge.  They were designed to gain more power from the cartridge than it was originally designed to produce, using modern smokeless powder and more robust case specifications.  And these rounds achieve this goal, producing about 100% greater muzzle energy for a given bullet weight over standard pressure .45 ACP rounds, and about a 50% increase over .45 ACP +P (over-pressure) rounds.

Take a look at the Muzzle Energy graph for .45 Super:

One thing I notice right away is that in general, the energy curve for this cartridge is much more pronounced and consistent than the energy curve for .45 ACP loads (whether standard pressure or +P). In other words, this is a round which continues to see impressive gains in energy over a longer barrel length, rather than flattening out starting at 8 – 10″. That’s more like the behavior you see from a magnum revolver round. Even the .460 Rowland tends to not see much gain after about 10″ — with the result that while the .460 Rowland is clearly a superior round for shorter barrels over the .45 Super, most loadings of the .45 Super meet or exceed the energy of the .460 Rowland by the time you get to carbine-length barrels. And you don’t need to rechamber your gun to shoot it.

Seeing this performance out of the Cx4 Storm actually prompted me to act on something I had just been thinking about: to go out and buy one of the remaining new Cx4 Storms out there (Beretta decided to discontinue the gun in that caliber earlier this year). In a future blog post I’ll talk about the alterations I am making to that gun, and that I have made to a Glock G30S, to handle the additional power of the .45 Super cartridge.

For now, enjoy playing with the data. And please be sure to share it with others! Because while I have long been an advocate for the .460 Rowland — a cartridge I still like very much — I now think that the .45 Super is a better choice for most people. Further discussion of that next time.

 

Jim Downey

October 30, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, .460 Rowland, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , | 6 Comments

Does primer size make a difference?

Following the success of our .45 Super/.450 SMC tests this summer, I sat down to work up some reloads which would mimic the factory ammo we had tested.

Since both of these cartridges are fairly unknown, there isn’t a whole lot of good information out there to draw upon. But there is some, at least for the .45 Super, and late last year/earlier this year I had worked up some preliminary loads, starting with .45 ACP +P (overpressure) published load data. But that was done using .460 Rowland cases and shot through my converted Glock G21, which I knew could handle the extra power. When reloading, it pays to be careful and conservative.

After I had seen the results from the extensive .45 Super/.450 SMC tests (some of which has already been published), I had a pretty good idea of where the power band for these loads was, and how different guns could handle it. Since I had previously worked up loads for .460 Rowland as well as done a lot of .45 ACP reloading over the years, I figured that I could come up with some pretty reasonable load levels to match what we had seen in the factory ammo.

So I sat down, looked through all my results and what was available elsewhere, and came up with loads* for three different bullet weights I had on hand: 185gr XTP, and 200gr & 230gr FP. I chose to use Longshot powder, which I have used successfully for both .45 ACP and .460 Rowland loads. (This is not an endorsement of any of these products, and I have not been compensated from these manufacturers in any way. This is just stuff I have on hand and know has worked previously.) I loaded 50 rounds each in .45 Super cases, using standard Large Pistol Primers.

But as I was doing so, I also realized that I had a bunch of .450 SMC cases left from the tests. And I figured that it might be an interesting experiment to load those cases to the exact same specs, other than the difference in primer size. To give the cartridge the benefit of better ignition, I used Small Magnum Pistol primers.  Again, I loaded 50 rounds of each bullet weight.

Again, other than the difference in primers, the reloads I worked up were identical.

 

OK, before I go any further, I want to toss in some caveats and explanations:

  1. This was an informal test, using only one chronograph and under less rigorous conditions than the formal BBTI tests. It was just me shooting a string of five shots, keeping mental track of what the numbers were for each, and then writing down a ballpark figure which seemed to best represent the overall performance. Also, I wasn’t using the BBTI light-frame which gives us more consistent chrono results.
  2. I was using my personal firearms, two of which (the Cx4 and Glock G30S) were brand new — this was their very first trip to the range. Yeah, I got them after seeing how similar guns performed in the .45 Super/.450 SMC tests earlier.

 

Now, about the guns used:

  • Glock G30S with a Lone Wolf 23lb recoil spring and steel guide rod package. 3.77″ barrel
  • Glock 21 converted to .460 Rowland (heavier recoil spring, compensator, and Lone Wolf .460 R barrel). 5.2″ barrel
  • Beretta Cx4 carbine, standard right out of the case. But I am going to install a steel guide rod and heavy buffer in it. 16.6″ barrel

 

Results:

Ammo                                     G30S                                    G21                                             Cx4

.45 Super 185gr                 1185 fps / 577 ft-lbs                1250 fps/ 642  ft-lbs             1550 fps / 987 ft-lbs

.450 SMC 185gr                 1125 fps / 520 ft-lbs                1200 fps / 592 ft-lbs             1500 fps / 925 ft-lbs

 

.45 Super 200gr                1130 fps / 567 ft-lbs                1225 fps / 667 ft-lbs              1420 fps / 896 ft-lbs

.450 SMC 200gr                1090 fps  / 528 ft-lbs               1180 fps / 619 ft-lbs              1420 fps / 896 ft-lbs

 

.45 Super 230gr                1080 fps / 596 ft-lbs                 1160 fps / 687 ft-lbs              1310 fps / 877 ft-lbs

.450 SMC 230gr                1060 fps  / 676 ft-lbs                1130 fps / 652 ft-lbs              1310 fps / 877 ft-lbs

 

Interesting, eh? What seems to be happening is that full ignition of the powder takes longer with the .450 SMC loads. That would explain why there’s more of a discrepancy with the lighter bullets and shorter barrels, so the bullet clears the barrel faster — some of the powder hasn’t yet ignited with the Small Magnum Primer. But with the heavier bullets and longer barrel of the Cx4, there more time for more of the powder to ignite, reducing or eliminating the difference in performance.

That’s my take on it. If you have another one, please comment.

Also, I want to note just how well I managed to emulate the performance of the factory ammo. Compare the numbers above with what I have already published for the Glock 21 and Cx4 used in the tests earlier. And it isn’t published yet, but the G30S numbers are also right on-the-money for how the G36 used in the tests earlier performed (the two guns have the same barrel length). In all instances, my reloads* performed within 10-15 fps of the factory loads.

 

Jim Downey

*So, what exactly were those loads specs? OK, here’s the data, but provided with the understanding that you should WORK UP YOUR OWN LOADS starting below these amounts, and accepting that you do so on your own responsibility. Also note that any changes in bullet weight, bullet brand, or powder type may/will alter the results you can expect. AGAIN: you use this data on your own responsibility. Be safe.

All bullet weights had a 1.250″ O.A.L.

All were given a slight taper crimp.

185gr XTP rounds had 11.0gr of Longshot powder.

200gr FP rounds had 10.5gr of Longshot powder.

230gr FP rounds had 10.0gr of Longshot powder.

October 21, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, .460 Rowland, Anecdotes, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , , , | 14 Comments

The illusion of precision.

Got an email which is another aspect of the problem I wrote about recently. The author was asking that we get more fine-grained in our data, by making measurements of barrel lengths by one-eighth and one-quarter inch increments. Here’s a couple of relevant excerpts:

what more is really needed, is barrel lengths between 1-7/8 and 4-1/2″.
because of the proliferation of CCW and pocket pistols, and unresolved
questions about short barrel lengths that go all over between 2 and 3.75″,
and snubby revolvers that may be even shorter.

* * *

with that amount of precision, not only would you have data covering all
lengths of short barrels, but you could fabricate mathematical curves that
would predict velocities for any possible barrel length, metric or
otherwise, given the particular ammo.

 

It’s not an unreasonable thought, on the surface. Our data clearly shows that the largest gains in bullet velocity always come in length increases of very short barrels for all cartridges/calibers. So why not document the changes between, say, a 4.48″ barrel and a 4.01″ one? That’s the actual difference between a Glock 17 and a Glock 19, both very popular guns which are in 9mm. Or between a S&W Model 60 with a 2.125″ barrel and a S&W Model 360PD with a 1.875″ barrel?

Ideally, it’d be great to know whether that half or quarter inch difference was really worth it, when taking into consideration all the other factors in choosing a personal defense handgun.

The problem is that there are just too many different variables which factor into trying to get really reliable information on that scale.

Oh, if we wanted to, we could do these kinds of tests, and come up with some precise numbers, and publish those numbers. But it would be the illusion of precision, not actually useful data. That’s because of the limits of what we can accurately measure and trust, as well as the normal variations which occur in the manufacturing process … of the guns tested; of the ammunition used; of the chronograph doing the measurements; even, yes, changes in ambient temperature and barometric pressure.

That’s because while modern manufacturing is generally very, very good, nothing is perfect. Changes in tolerance in making barrels can lead to variation from one gun to the next. Changes in tolerance in measuring the amount of gunpowder which goes into each cartridge (as well as how tight the crimp is, or even tweaks in making the gunpowder itself) mean that no two batches of ammunition are exactly alike. And variations in making chronographs — from the sensors used, to slight differences in positioning, to glitches in the software which operate them — mean that your chronograph and mine might not agree on even the velocity of a bullet they both measure.

All of those little variations add up. Sometimes they will compound a problem in measuring. Sometimes they will cancel one another out. But there’s no way to know which it is.

This is why we’ve always said to consider our data as being indicative, not definitive. Use it to get a general idea of where your given choice of firearm will perform in terms of bullet velocity. Take a look at general performance you can expect from a brand or line of ammunition. Compare how this or that particular cartridge/caliber does versus another one you are considering.

But keep in mind that there’s no one perfect combination. You’re always going to be trading off a bunch of different factors in choosing a self-defense tool.

And never, ever forget that what matters most — FAR AND ABOVE your choice of gun or ammunition — is whether or not you can use your firearm accurately and reliably when you need to. Practice and training matters much more than whether or not you get an extra 25, or 100, or even 500 fps velocity out of whatever bullet is traveling downrange. Because if you can’t reliably hit your target under stress, no amount of muzzle energy is going to do you a damn bit of good.

 

Jim Downey

If you want more information about how accuracy and precision can be problematic, this Wikipedia entry is a good place to start.

September 6, 2015 Posted by | .357 Magnum, .38 Special, 9mm Luger (9x19), Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , | 2 Comments

Now, *that’s* customer service.

Remember this guy?

with mag

Well, earlier this summer my pistol suffered a mechanical problem with what Boberg calls the ‘lift mechanism’ — the part which grabs a cartridge out of the magazine and pulls it back and up to position it for loading into the chamber. Basically, a pin which helps hold the mechanism in place broke, and the gun locked up.

I contacted Boberg, told them what happened, sent along some pics. They immediately responded, said that it was likely that since the gun was such a low serial number (just 0120) it had one of an early batch of pins which had substandard quality control. No biggie. They sent out a pick-up tag so I could ship it directly to them. About two weeks later (including shipping time), I had the gun back, with a new pin, all ready to go — without it costing me a cent.

Cool, right?

A couple days later I took it out to the range to see how it was working. And on the 19th round fired, it locked up again. Exact same way.

I contacted Boberg again. Again, they responded immediately. And they were astounded that it had happened a second time. The lead smith for the company queried me about the specifics of what happened, what ammo I was using, etc. Not because he thought that I was trying to pull a fast one, but because he was genuinely baffled how this could happen twice. Without hesitation they sent out another pick up tag, and I shipped the gun back in the same box it had arrived in a couple days previously. And I told them that they could take their time to investigate what happened — that I was in no hurry to have the gun back, and that above all I wanted a reliable gun rather than a quick turn-around. The lead smith understood and agreed completely.

So, a couple weeks later I got the gun back. Just yesterday, as a matter of fact (I asked them not to ship it until I was back from vacation). And I have yet to get out to test it myself. But this is what was in the box with the gun:

20150822_080243

I want to point to the first item on the invoice, which says:

Repair of firearm. RA#611, Serial #S450120. (Replaced broken lift mechanism. Put 250 rounds through it. Passed test firing.)

They ran 250 rounds through it. Not just one (which is typical for a test firing), or even a mag full (6 rounds). 250. That’s easily $100 of ammo. And probably a couple hours of someone’s time. Because like me, they wanted to make sure the gun was functioning reliably.

Now, *that*, my friends, is customer service.

Anything mechanical can break down. Even the best made items can have weird failures, regardless of the quality of materials or the care of a craftsman. It happens. I’m a conservator of rare books and documents, and it has happened in my work. What matters is whether the person/company behind that product will stand by their work and make it good.

Boberg has. Kudos to them.

Jim Downey

PS: Just for grins, here’s a pic of the interior I took before cleaning the gun this morning:

20150822_113419

August 22, 2015 Posted by | .45 ACP | , , , , , , , , | 4 Comments

Saying farewell to an old friend.

I’ve decided to say farewell to an old friend who has rarely left the safe in the last couple of years.

So if you know anyone who might be interested in a very early (and collectible) Rohrbaugh R9, have ’em take a look at these images and then go on over to Gunbroker (I’ll link to the auction when it is live). I’m selling the gun with all the items shown.

Left

Rohrbaugh R9

Right

Internals

Internals

Frame interior

Frame interior

Underside

Underside

Holstered

In custom pocket holster

Holstered2

Holster has a detachable back to mask the shape of the gun

Kit

Original case & paperwork, replacement springs, take-down tool set are all included.

As I noted in my review of the R9 from three years back, it’s a fantastic little firearm, and incredibly well made. But as I also noted in that review, I had stopped carrying it much even then. I realized recently that I hadn’t taken it out to shoot for a couple of years. And that just ain’t right.

So I’m going to find it a new home. One where it will be appreciated.

Spread the word. Thanks.

Jim Downey

EDITED TO ADD: Sale concluded happily, and this nice little gun has found a new home. Thanks, everyone!

August 19, 2015 Posted by | 9mm Luger (9x19), Links | , , , , , | 5 Comments

Do you want good data, or useable data?

Got a question I haven’t seen for a while. Here it is, with my answer (and a little bit of additional explanation) to follow:

Thanks for the site!  You do not post the altitude and  temperature of your results (unless I missed that).  Can you let us know what your reference points are?  Also, what effect would altitude and temperature variation have on your results?

Here’s the answer I gave:

Well, it’s been a while since anyone asked about that … thanks!

We did discuss this early on, and decided pretty quickly that while both of those would indeed have an effect (as would the changes in barometric pressure), that it would be so small as to not matter for the degree of accuracy of our testing equipment and the limited number of rounds tested. If you were trying to get really good data, everything would have to be much more rigorous and controlled … and we would never ever have gotten the data that we did. So as I remind people: consider the results to be *indicative*, not definitive. In other words, don’t try to read too much into variances of a few feet-per-second, or convince yourself that such minor differences really matter.

Hope that helps to give a little perspective.

Oh, and I can answer one of your questions: almost all the testing was done at an elevation of approximately 744′ above sea level, according to commercial GPS systems.

I think that’s pretty clear, but I want to emphasize one part of it: that if we had set out to provide really rigorous and statistically-significant data, the chances are that we would never have even gotten past the first test sequence. And that means there would be NO BBTI.

As it is, we have tested something in excess of 25,000 rounds over the last 7 years. At a personal cost of more than $50,000. And that doesn’t begin to include the amount of labor which has gone into the project. To get really solid data which was statistically significant, we probably would have needed to do at LEAST three or four times as many rounds fired. With three or four times the amount of time testing. And crunching the data. And cost out of pocket.

Which would have meant that we probably would never have gotten through a single test sequence.

So it’s a matter of perspective. Do you want some data which is reasonably solid, and gives a pretty good idea of what is going on with different cartridges over different barrel lengths? Or do you want very accurate, high rigorous data which would never have been produced?

Hmm … let me think about that …😉

 

Jim Downey

PS: We haven’t forgotten about the .45 Super/.450 SMC tests — it’s just been a busy summer. Look for it soon.

August 11, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, .460 Rowland, Data, Discussion., General Procedures | , , , , , , , , , , , , , , | 1 Comment

Some “Super” performance out of a Cx4 Storm.

This is the third in a series of informal blog posts about the .45 ACP/Super/.450 SMC testing sequence we conducted over the Memorial Day weekend. You can find the previous posts here and here.

Today we’re going to look at the results out of a stock Beretta Cx4 Storm in (obviously) .45 ACP. I have previously reviewed the Cx4 Storm in .45 ACP for Guns.com, and it is a great little pistol caliber carbine with a 16.6″ barrel. Here is Keith shooting the one we used for this recent testing:

Cx4

I want to re-iterate that the Cx4 was completely stock, with no modifications or additions whatsoever for these tests.

As I said with the previous posts about these tests, it’ll be a while before we have all the data crunched and the website updated, but I thought I would share some preliminary thoughts and information through a series of informal posts.

Quick note about the data below: All the ammo used, with the exception of the four * items, were part of our overall test sequence and had three shots made over the Oehler chronograph (which is a double-unit, and automatically records and then averages the two readings), representing a total of 6 data points. I’m just giving the overall averages here; the full data will be available on the website later. The four * ammunition types only include two shots/four data points through the Cx4. That’s because we only had one box of each of this ammo, and were wanting to get data which would be of the greatest use to the largest number of people.

Ammo                                                                               Cx4 Storm

      Buffalo Bore

.45 ACP Low Recoil Std P 185gr FMJ-FN                 997 fps / 408 ft-lbs

.45 ACP Std P 230gr FMJ-RN                                933 fps / 444 ft-lbs

.45 ACP +P 185gr JHP                                       1361 fps / 760 ft-lbs

.45 ACP +P 230gr JHP                                       1124 fps / 645 ft-lbs

.45 Super 185gr JHP                                         1555 fps / 993 ft-lbs

.45 Super 200gr JHP                                         1428 fps / 905 ft-lbs

.45 Super 230gr FMJ                                         1267 fps / 819 ft-lbs

.45 Super 230gr JHP                                         1289 fps / 848 ft-lbs

.45 Super 255gr Hard Cast                                 1248 fps / 881 ft-lbs

      Double Tap

.45 ACP +P 160gr Barnes TAC-XP                        1315 fps / 614 ft-lbs

.450 SMC 185gr JHP                                          1618 fps / 1075 ft-lbs

.450 SMC 185gr Bonded Defense JHP                  1556 fps / 994 ft-lbs

.450 SMC 230gr Bonded Defense JHP                  1298 fps / 860 ft-lbs

      Hornady

Critical Defense .45 ACP Std P 185gr FTX              1161 fps / 553 ft-lbs

Critical Duty .45 ACP +P 220gr Flexlock                 1018 fps / 506 ft-lbs

      Underwood

.45 Super 170gr CF                                           1421 fps / 762 ft-lbs

.45 Super 185gr XTP JHP                                   1578 fps / 1022 ft-lbs

.45 Super 230gr GD JHP                                     1264 fps / 815 ft-lbs

*Federal  HST .45 ACP Std P 230gr JHP                882 fps / 397 ft-lbs

*G2 Research  RIP  .45 ACP Std P 162gr JHP        979 fps / 344 ft-lbs

*LeHigh Defense .45 Super 170gr JHP               1289 fps / 627 ft-lbs

*Liberty  Civil Defense .45 ACP +P 78gr JHP        2180 fps / 822 ft-lbs

Something in particular I want to note: that in comparison to .45 ACP loads (whether standard pressure or +P), a number of the .45 Super/.450 SMC loads gain significantly more from the longer barrel. Compare these numbers to the previous posts of handguns, and you can see what I mean. You typically only gain about 10 – 15% in terms of velocity from the .45 ACP loads in going to a carbine — and this is very much in keeping with our previous testing of that cartridge. But you see upwards of a 30% gain in velocity out of some of the .45 Super/.450 SMC loads … and that translates to a 50% increase in muzzle energy!

A heavy, large projectile hitting with 900 – 1,000 foot-pounds of energy is nothing to sneeze at. Particularly when it comes with very little felt recoil out of this little carbine. That means you can get quick and accurate follow-up shots, which is always an advantage when hunting or using a gun for self/home defense.

As noted previously, we noticed no unusual wear on the Cx4 Storm, though a steady diet of such ammo could increase wear on the gun over time. And the Beretta didn’t have any problems whatsoever feeding, shooting, or ejecting any of the rounds. Where we had experienced some problems with the same ammo out of some of the handguns, there wasn’t a hiccup with the Cx4 Storm.

Look for more results, images, and thoughts in the days to come.

Jim Downey

June 16, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , , , , , , , , , , | 11 Comments

There’s got to be an easier way …

… to get all this brass cleaned:

20150612_123003

😉

Have a great weekend, everyone!

 

Jim Downey

June 12, 2015 Posted by | .45 ACP, .45 Super, .450 SMC | , , , , , , | Leave a comment

Ammo test results for a pair of 1911s

This is the second in a series of informal blog posts about the .45 ACP/Super/.450 SMC testing sequence we conducted over the Memorial Day weekend. You can find the previous post here.

Today we’re going to see what the results are for a couple of different high-end 1911 platform guns. The first is an Ed Brown Kobra Carry (reviewed here), a Commander-sized (4.25″ barrel) single stack designed as a concealed-carry gun. We made no modifications of it for the more powerful loads. Here it is during our testing:

Ed Brown

The second is a Wilson Combat Hunter set up for the .460 Rowland cartridge with a 5.5″ barrel. Here’s my review of it, and here it is on the day of testing:

Wilson hunter

As I said with the other two posts about these tests, it’ll be a while before we have all the data crunched and the website updated, but I thought I would share some preliminary thoughts and information through a series of informal posts.

Quick note about the data below: All the ammo used, with the exception of the four * items, were part of our overall test sequence and had three shots made over the Oehler chronograph (which is a double-unit, and automatically records and then averages the two readings), representing a total of 6 data points. I’m just giving the overall averages here; the full data will be available on the website later. The four * ammunition types only include two shots/four data points through the Ed Brown Kobra Carry,  since it is a typical length for a self-defense gun. That’s because we only had one box of each of this ammo, and were wanting to get data which would be of the greatest use to the largest number of people.

Ammo                                                         Ed Brown Kobra Carry              Wilson Combat Hunter

      Buffalo Bore

.45 ACP Low Recoil Std P 185gr FMJ-FN                 798 fps / 261 ft-lbs                       791 fps / 256 ft-lbs

.45 ACP Std P 230gr FMJ-RN                                811 fps / 335 ft-lbs                       819 fps / 342 ft-lbs

.45 ACP +P 185gr JHP                                       1130 fps / 524 ft-lbs                     1139 fps / 532 ft-lbs

.45 ACP +P 230gr JHP                                        952 fps / 462 ft-lbs                       970 fps / 480 ft-lbs

.45 Super 185gr JHP                                         1257 fps / 648 ft-lbs                     1312 fps / 706 ft-lbs

.45 Super 200gr JHP                                         1175 fps / 613 ft-lbs                     1216 fps / 656 ft-lbs

.45 Super 230gr FMJ                                         1067 fps / 581 ft-lbs                     1105 fps / 623 ft-lbs

.45 Super 230gr JHP                                         1084 fps / 600 ft-lbs                     1109 fps / 627 ft-lbs

.45 Super 255gr Hard Cast                                 1061 fps / 637 ft-lbs                     1074 fps / 653 ft-lbs

      Double Tap

.45 ACP +P 160gr Barnes TAC-XP                        1121 fps / 446 ft-lbs                     1162 fps / 479 ft-lbs

.450 SMC 185gr JHP                                          1310 fps / 704 ft-lbs                     1350 fps / 748 ft-lbs

.450 SMC 185gr Bonded Defense JHP                  1254 fps / 645 ft-lbs                     1294 fps / 687 ft-lbs

.450 SMC 230gr Bonded Defense JHP                  1103 fps / 621 ft-lbs                     1108 fps / 626 ft-lbs

      Hornady

Critical Defense .45 ACP Std P 185gr FTX               969 fps / 385 ft-lbs                       976 fps / 391 ft-lbs

Critical Duty .45 ACP +P 220gr Flexlock                  932 fps / 424 ft-lbs                       936 fps / 427 ft-lbs

      Underwood

.45 Super 170gr CF                                           1249 fps / 588 ft-lbs                     1259 fps / 598 ft-lbs

.45 Super 185gr XTP JHP                                   1285 fps / 678 ft-lbs                     1339 fps / 736 ft-lbs

.45 Super 230gr GD JHP                                     1071 fps / 585 ft-lbs                    1099 fps / 616 ft-lbs

*Federal  HST .45 ACP Std P 230gr JHP                815 fps / 339 ft-lbs

*G2 Research  RIP  .45 ACP Std P 162gr JHP        961 fps / 332 ft-lbs

*LeHigh Defense .45 Super 170gr JHP               1165 fps / 512 ft-lbs

*Liberty  Civil Defense .45 ACP +P 78gr JHP         1843 fps / 588 ft-lbs

As with the other guns I’ve posted about, the general trends are pretty clear with the power rising as you go from standard pressure to +P to Super/.450 SMC, and topping out at about 750 foot-pounds of energy in a couple of loads. And it is interesting to note that the 185gr loads seem to be the “sweet spot” in terms of power across the board.

Of course, pure power is just one component for what makes a good ammunition choice. Bullet design & penetration is extremely important when considering a self-defense load. Shootability in your gun is also critical — because if you can’t recover quickly from shot to shot, then you may limit your ability in a stressful situation. Likewise, if the ammo doesn’t function reliably, or damages your gun, that is also a huge factor.

Most of the ammo we tested functioned very well in both 1911 platforms.  Interestingly, while we had experienced FTFs (failure-to-fire) with a number of the different Double-Tap rounds in both the Bobergs and the Glocks, we didn’t experience any such problems with either 1911.

The larger platform of the Wilson Combat Hunter handled the recoil very well, even from the hottest loads. Recoil was a little more noticeable with the Ed Brown, but only by a slight amount. As I noted with the Glock 21 converted for the .460 Rowland,  I was impressed that The Wilson Combat Hunter didn’t have any problems cycling even the lightest loads reliably.

Another note: we were unable to detect any damage or unusual wear to either gun, though it is possible a steady diet of loads of that power could cause some over the long term.

Lastly, I ran some .460 Rowland Buffalo Bore 230gr JHP cartridges through the Wilson Combat Hunter, since we had only had one type of ammo for that gun when we did the .460 Rowland tests.  That had been Cor-Bon Hunter 230gr JHP. The Cor-Bon tested at 1213 fps / 751 ft-lbs, and the Buffalo Bore tested at 1349 fps / 929 ft-lbs of energy.

Look for more results, images, and thoughts in the days to come.

Jim Downey

June 9, 2015 Posted by | .45 Colt, .45 Super, .450 SMC, .460 Rowland, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , , , , , , , , , , , , | 3 Comments

“How can I use your data?”

We get a fair number of questions to the BBTI email account ( info@ballisticsbytheinch.com ), which I try to answer as quickly as my time will allow. Most are about specific points in our data, or why we did this or that in our procedures (answers to most such can be found in our FAQ). But every once in a while a question comes along which pushes me to re-think things from another vantage point. The following is one such from “drglenn”, and I thought I would share it and my answer:

Found your website interesting, but I am uncertain how I can use this data reliably for me. Perhaps you can offer some guidance. Clearly, barrel length data can be used relatively to compare any single caliber/brand/bullet mass to itself. This is useful to see muzzle velocities/energy as a function of barrel length which might help the consumer in determining just how much more value they will get by purchasing a longer barreled firearm. What I found frustratingly non-useful is an inability to compare bullet mass to velocity/energy across brands – or even within a single brand – of stock ammo. This, no doubt, is a function of powder composition, cartridge air-space volume, and quantity of said powder. One might reasonably assume that, every other parameter being equal, a bullet with more mass, will have a lower muzzle velocity. One might also reasonably assume that since E=1/2mv^2, that velocity is much more significant than bullet mass in determining energy (i.e., all else being equal, if you could double the velocity, you would get 4x the energy, while doubling the mass will only yield twice the energy). Apparently, this useful bit of physics becomes completely useless as each manufacturer uses different powder formulations and quantities for their ammo. So, while I may be able to determine that, across the board, a certain mass bullet or higher, in a certain caliber, regardless of manufacturer, may be subsonic, it would be a crap-shoot in guessing which mass and which manufacturer should have the highest muzzle energy in a given barrel length.

Suggestions for best use of your data would be appreciated!

Sorry, I’m not quite sure what you’re asking. You’re correct that because of proprietary powder formulations, there’s no easy comparison between different manufacturers or even between different ‘lines’ of product from a given manufacturer. In fact, the situation is even much worse than you state, because the manufacturers are *constantly* tweaking their formulations in an effort to claim more of the market. And then there’s the whole matter of terminal ballistic performance depending on the actual bullet design and composition. Toss in the fact that firearms manufacturers are also constantly making minor alterations to their models and production methods, and yeah, it’s impossible to say with any certainty that this or that combination of gun and ammo will give a reliable result. In short, there is no “perfect” solution to the very complex problems of ballistics — one of the reasons why it has a long history of attracting some of the finest minds in physics.

But you can gain insight in what to expect within certain parameters using our data. You can see that while most semi-auto handgun ammunition performs best in a certain range of barrel lengths — usually from 3″ to 8″ –, that ‘magnum’ rounds intended primarily for revolvers will continue to gain velocity/energy over a much longer range of barrel lengths, and so is more suitable for a carbine. You can tell that most ammo formulated to be “low recoil” means that it has less overall velocity/energy, since you can’t break the laws of physics. You can see that some manufacturers may claim performance standards which aren’t supported by our tests, and some are right on the money. You can argue with your friends over a beer whether it is better to use a slow heavier bullet or a lighter one which goes much faster.

In short, our data is a tool for helping analysis and decision-making, nothing more. It’s certainly not perfect. It’s not even comprehensive within a given caliber/cartridge. And it is in some sense rendered obsolete each and every time the manufacturers tweak their production materials or methods. Which is why we always tell people to consider it indicative, not definitive. Use it if it makes sense for your needs, don’t if it doesn’t. And always – ALWAYS – know that testing your own ammo out of your specific gun is the only way to know for sure how it will perform.

Hope this helps.

Jim Downey

June 4, 2015 Posted by | Data, Discussion., General Procedures | , , , , , , , | Leave a comment

Ammo test results in two versions of the Glock 21

This is the first in a series of informal blog posts about the .45 ACP/Super/.450 SMC testing sequence we conducted over the Memorial Day weekend.

Here’s a pic of getting set the first day of shooting:

getting set

It’ll be a while before we have all the data crunched and the website updated, but I thought I would share some preliminary thoughts and information through a series of informal posts. In this post, we’ll see how two different versions of a Gen 4 Glock 21 performed with the ammo. The first version was with the Glock in the standard .45 ACP configuration, the second was with my .460 Rowland conversion kit in place.

The standard configuration has a 4.61″ octagonal polygonal rifling, while the conversion barrel is 5.2″ overall with conventional rifling, threaded, and with a compensator. The .460 conversion also has a heavier recoil spring.

Quick note about the data below: All the ammo used, with the exception of the four * items, were part of our overall test sequence and had three shots made over the Oehler chronograph (which is a double-unit, and automatically records and then averages the two readings), representing a total of 6 data points. I’m just giving the overall averages here; the full data will be available on the website later. The four * ammunition types only include two shots/four data points through the standard Glock 21 configuration — we only had one box of each of this ammo, and were wanting to get data from a range of guns.

Ammo                                                         Glock 21 Standard                   Glock 21 .460 Rowland

      Buffalo Bore

.45 ACP Low Recoil Std P 185gr FMJ-FN                 801 fps / 263 ft-lbs                       792 fps / 257 ft-lbs

.45 ACP Std P 230gr FMJ-RN                                829 fps / 350 ft-lbs                       826 fps / 348 ft-lbs

.45 ACP +P 185gr JHP                                       1132 fps / 526 ft-lbs                     1168 fps / 560 ft-lbs

.45 ACP +P 230gr JHP                                        951 fps / 461 ft-lbs                       974 fps / 484 ft-lbs

.45 Super 185gr JHP                                         1279 fps / 671 ft-lbs                     1299 fps / 693 ft-lbs

.45 Super 200gr JHP                                         1178 fps / 616 ft-lbs                     1203 fps / 642 ft-lbs

.45 Super 230gr FMJ                                         1069 fps / 583 ft-lbs                     1085 fps / 601 ft-lbs

.45 Super 230gr JHP                                         1094 fps / 611 ft-lbs                     1116 fps / 635 ft-lbs

.45 Super 255gr Hard Cast                                 1063 fps / 639 ft-lbs                     1061 fps / 637 ft-lbs

      Double Tap

.45 ACP +P 160gr Barnes TAC-XP                        1103 fps / 432 ft-lbs                     1103 fps / 432 ft-lbs

.450 SMC 185gr JHP                                          1328 fps / 724 ft-lbs                     1351 fps / 749 ft-lbs

.450 SMC 185gr Bonded Defense JHP                  1301 fps / 695 ft-lbs                     1314 fps / 709 ft-lbs

.450 SMC 230gr Bonded Defense JHP                  1097 fps / 614 ft-lbs                     1132 fps / 654 ft-lbs

      Hornady

Critical Defense .45 ACP Std P 185gr FTX               984 fps / 397 ft-lbs                       979 fps / 393 ft-lbs

Critical Duty .45 ACP +P 220gr Flexlock                  945 fps / 436 ft-lbs                       943 fps / 434 ft-lbs

      Underwood

.45 Super 170gr CF                                           1239 fps / 579 ft-lbs                     1253 fps / 592 ft-lbs

.45 Super 185gr XTP JHP                                   1329 fps / 725 ft-lbs                     1348 fps / 746 ft-lbs

.45 Super 230gr GD JHP                                    1075 fps / 590 ft-lbs                     1081 fps / 596 ft-lbs

*Federal  HST .45 ACP Std P 230gr JHP                813 fps / 337 ft-lbs

*G2 Research  RIP  .45 ACP Std P 162gr JHP        942 fps / 319 ft-lbs

*LeHigh Defense .45 Super 170gr JHP              1146 fps / 495 ft-lbs

*Liberty  Civil Defense .45 ACP +P 78gr JHP        1768 fps / 580 ft-lbs

The general trends are pretty clear with the power rising as you go from standard pressure to +P to Super/.450 SMC, and topping out at about 750 foot-pounds of energy in a couple of loads. And it is interesting to note that the 185gr loads seem to be the “sweet spot” in terms of power across the board.

Of course, pure power is just one component for what makes a good ammunition choice. Bullet design & penetration is extremely important when considering a self-defense load. Shootability in your gun is also critical — because if you can’t recover quickly from shot to shot, then you may limit your ability in a stressful situation. Likewise, if the ammo doesn’t function reliably, or damages your gun, that is also a huge factor.

Most of the ammo we tested functioned very well in the Glock in either configuration. This isn’t surprising to anyone who has much familiarity with Glocks which typically will handle just about any ammo under all conditions. We did experience FTFs (failure-to-fire) with a number of the different Double-Tap rounds. Those seemed to have been due to light strikes on the primer, which could have been due to improper primer seating, ‘hard’ primers, or some other factor.

The larger platform of the Glock 21 handled the recoil very well, even from the hottest loads. I was impressed that even with the .460 Rowland conversion in place, with the additional weight of the compensator and the heavy recoil spring, the Glock didn’t have any problems cycling even the lightest loads reliably.

One other note: as discussed in my blog post about the .460 Rowland conversion, full-power .460 Rowland loads tend to cause damage to the magazines. As far as we could tell, the same isn’t true of the full-power .45 Super/.450 SMC loads. Just one magazine (a new one) was used for all these tests, and there was no detectable damage. Nor was there any other damage detected to the gun otherwise, though it is possible a steady diet of loads of that power could cause some over the long term.

Look for more results, images, and thoughts in the days to come.

Jim Downey

June 1, 2015 Posted by | .45 ACP, .45 Super, .450 SMC, .460 Rowland, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , , , , , , , , , | 6 Comments

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