Ballistics by the inch

Perceived recoil and bullet weight.

Got a great question recently, and I thought I would share some of my thoughts about it, then invite others to weigh in. Here’s the question:

I hope that you folks can help me with a question I have had for many years now. Why is the recoil so much heavier with lighter bullets in the same caliber and powder loadings than heavier bullets of the same caliber and loadings?

For example. With my S&W model 60, Gold Dot L/E 38 special 135 grain JHP +P loads recoil much harder than the Remington 125 grain JHP +P loads. The same thing happens with my Glock mod 23 .40cal when I shoot 180 grain JHP rounds vs 165 grain JHP rounds. The 165 grain rounds recoil much harder. One would think the heavier round with the same powder load would recoil harder. Can you help?

Perceived recoil is a surprisingly complex problem. It’s not just a matter of total force, but the ‘shape’ of the recoil impulse as well. Then there are the ergonomics of how a particular gun fits a particular person/hand. Add in the mechanical action of how the gun operates (some use part of the recoil energy to cycle the action, some don’t), and various psychological/physiological factors (are you tired? just had an adrenaline dump? afraid of a given gun/caliber/cartridge?), and you can see how many different factors might come into play.

A good place to start is to look at the equation for Muzzle Energy (ME). Let’s use the numbers for the Steyr M40 (very similar to your Glock 23) which was one of the ‘real world’ guns used in the .40 S&W tests we did. Calculations are from Airhog.

The 165gr Federal Hydra-Shok JHP has a velocity of 943fps out of the 4″ barrel. That gives a Muzzle Energy of 325.88ft-lbs.
The 180gr Federal Hydra-Shok JHP has a velocity of 989fps out of the 4″ barrel. That gives a Muzzle Energy of 391.04ft-lbs.

OK, that would seem to indicate that the heavier bullet should cause more recoil. The ME is higher, and you’re shooting them out of the same gun.

But I’m a little wary of that example. Usually, a lighter bullet is faster than a heavier one if they have the similar powder charge, out of barrels of the same length. Here’s another example, looking at 9mm from a Beretta 92.

The Cor-Bon 90gr JHP +P has a velocity of 1522 out of the 4.875″ barrel. That gives a Muzzle Energy of 463.05ft-lbs.
The Cor-Bon 125gr JHP +P has a velocity of 1291 out of the 4.875″ barrel. That gives a Muzzle Energy of 462.72ft-lbs.

And those are very close to the same amount of ME, and should feel about the same in terms of recoil were that the only factor.

So what’s going on? Why do we see one instance where the ammo is just a bit faster in the heavier bullet (resulting in higher ME), but much slower in another instance?

I suspect that it’s probably due to differences in loadings between the different ammo. Even with ammo from the same manufacturer (in the examples above), there’s nothing saying that they are using either the same propellant OR similar amounts of the same propellant for loadings which use different bullet weights. That means that trying to generalize the amount of recoil between different bullet weights just on the basis of brand is difficult if not impossible.

Furthermore, if you’ve done any reloading, or spend some time looking over reloading data, you’ll know that even when you’re using the same propellant in the same cases, different bullet weights usually means different bullets (in terms of manufacturer and/or shape) resulting in different seating depths and overall length. It may seem to be a trivial matter, but this results in different pressure profiles (the amount of pressure within the firing chamber of the gun). Just one example, taken from the Hodgdon Reloading site, for maximum-pressure loads using  GDHPs:

The 90gr bullet with 7.0gr of Longshot powder has an overall length of 1.010″ and gives a velocity of 1,378fps, a pressure of 32,300 PSI, and would have a ME of 379.57ft-lbs.
The 115gr bullet with 6.0gr of Longshot powder has an overall length of
1.125″ and gives a velocity of 1,203fps, a pressure of 32,300 PSI and would have a ME of 369.64ft-lbs.

Note that while the heavier bullet uses a full 1.0gr less of propellant and has a longer overall length, it generates the same amount of pressure. If we drop back to the same amount of the same powder for each loading (6.0gr), then the pressure generated in the lighter bullet loading drops to 29,400 PSI, velocity drops to 1,278fps, and ME drops to 326.48ft-lbs.

But not all pressure is created equal, even if it is nominally ‘the same’. The pressure impulse also matters. That’s the curve of how the pressure rises and falls over time, which is largely related to how ‘fast’ or ‘slow’ the propellant burns. Propellants used for handgun loads tend to be very ‘fast’ (burn rapidly), so the impulse tends to be sharper.  Here’s a good explanation of the matter.

And if you think about it, the heavier the bullet used, the longer/slower it takes to start moving when the cartridge is fired. That should mean that the impulse is spread out over a slightly longer time than it would be with a lighter bullet. So in some sense, the lighter bullet would result with a ‘snappier’ feel. And that may well be what it is that you’re feeling when you experience more perceived recoil (and have controlled for all the other factors) from lighter bullets.

Other thoughts on the subject?

 

Jim Downey

 

 

 

 

June 15, 2014 Posted by | .38 Special, .40 S&W, 9mm Luger (9x19), Data, Discussion., Links | , , , , , , , , , , , , , , , | Leave a comment

Questions, we get questions …

I thought I would share a question I got in email today, and my generalized answer, since it is something which comes up surprisingly often.

 

I love this data! Would it be possible to fund the testing of additional cartridges?  I’m looking for more .XYZ load tests.

Our baseline costs for testing a particular cartridge (out to 18″ barrel length) runs a couple hundred dollars for the barrel blank, then perhaps another hundred to get the smithing work done on it to fit the T/C platform. Then add in the actual cost of ammo, with a minimum of probably 100 rounds (3 shots at each inch of barrel, additional rounds for each ‘real world gun’, and then another box or two for repeats when something goes buggy with the data). So realistically, to actually fund a test sequence is a minimum of close to $500 for just one ammo load, and another $100+ for each additional ammo. Add in equipment and site hosting costs, and that’s how we’ve managed to spend something on the order of $50k so far for the data on the site. Which doesn’t include any labor costs, of course, since we only do this because we were curious about the data, not as any kind of testing business.

Which is to say that we’re always happy to accept donations and feedback on what sorts of things people would like to see, but as of yet no one has been willing to step up and finance an entire test sequence for something we’re curious enough to want to sink the time into. (Each test sequence takes 100 man-hours of labor or more … from our vacation/weekend/fun time.)

We don’t *currently* have any plans to retest the .XYZ anytime soon. Actually, we don’t have plans to do any specific tests at all in the near term. But we are looking at revisiting most or all of the cartridges tested to date at some point in the future, just to see how ammo quality/selection may have changed over a 5 or 10 year period.

 

Jim Downey

June 5, 2014 Posted by | Anecdotes, Data, Discussion., General Procedures | , , , , , , , , , | Leave a comment

Confirmation of the .460 Rowland performance.

John Ervin at Brass Fetcher Ballistic Testing has just put up a new page about his testing of the .460 Rowland cartridge. As I have explained in the past,  our work at BBTI is intended to be an overview of how ballistic performance varies over barrel length — it is just a quick survey to get an idea of the general trends, not meant to be an in-depth examination of a specific cartridge.

But in-depth testing is exactly what Ervin does, using a larger sample size, ballistic gelatin, and high-speed videography. And as a result, his much more detailed analysis is more useful for getting into the details of a given cartridge out of a specific barrel length. And it is really good to see that his results confirm what I have been saying all along: that if you carry a .45, you should instead be carrying a .460 Rowland.

What specifics? Take a look at the performance of Speer 230gr Gold Dot HP .45ACP in terms of foot-pounds of kinetic energy transfer into 20% ballistic gel:

 

Pretty good, eh? It’s what we expect from the .45ACP: a solid energy dump and reasonable penetration.

Now let’s take a look at the same chart, but with the Speer 230gr Gold Dot HP in .460Rowland:

The curves don’t look that different on first glance, but pay close attention to the scale there on the left axis of each one: where the .45ACP tops out at about 72 ft/lbs about 2″ into the gel, the .460Rowland tops out at about 335 ft/lbs just before 2″. That’s more than 4x the energy transfer.

In fact, at 5″ of penetration, the .460Rowland is still dumping about as much energy as the .45ACP does at the maximum.

But there’s more than simple energy transfer involved in terminal ballistic performance. There’s also how well the bullet is designed, and whether it expands properly. This can be a big concern in “over-driving” a bullet, so that it breaks apart. Well, Ervin’s data also covers these comparisons quite well. For the two specific rounds cited above, the .45ACP expanded to 0.344 square inches of frontal surface, and was still 229.5gr of weight. And the .460Rowland expanded to 0.526 square inches of frontal surface, and was still 221.3gr of weight.

There’s a *LOT* more information at Brass Fetcher Ballistic Testing. Ervin has an extensive 17 page Ammunition Performance Data report in .pdf format which contains a ton of images, video, and data — more than enough to keep even a data-junkie like me busy for a long time. I urge you to take a good look at it, and to consider the thoughts which Ervin shares about this cartridge. But I will leave you with his opening sentence which sums it up very nicely:

The 460 Rowland represents the pinnacle of handgun calibers for self-defense.

 

Agreed.

Jim Downey

May 1, 2014 Posted by | .45 ACP, .460 Rowland, Data, Discussion., Links | , , , , , , , , , , , , , , , , , | Leave a comment

Stereotomy*

Cross posted  from my personal blog.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For those who don’t know, one of my other interests is handgun ballistics research. Specifically, in regards to how barrel length effects bullet velocity for different cartridges and loadings. Even if you don’t like guns, the physics behind ballistic performance can be very interesting.

And here’s a wonderfully graphic image showing those physical forces:

Ruger Alaskan .44 Magnum

Text from the source to go with this image (site is Finnish, and English is not the author’s first language):

Let’s talk a bit about .44 Magnum cartridge. Despite of being very close to diameter of .45ACP the .44Mag is totally different beast. Average .45ACP round generates ~650J of hit energy while .44Mag makes easily 1600J and can be pushed much more beyond that. This specific gun however cannot utilize all potential of .44 Magnum cartridge because of very short barrel. It simply cannot burn all powder. As you can see there is huge cone shaped spray of unburnt stuff flying in the air. With longer barrel show would be different.

Ok, you may have noticed the flames. They are something we haven’t seen before. Especially when you look picture below and huge left side flame in it. Interesting thing is that major amount of the flame is escaping between cylinder and barrel. That short barrel seems to puff bullet our so fast that powder mass just flies out unignited.

The site is filled with a bunch of great high-speed camera images of guns being fired. And it also has something else which is new to me: ‘natural stereoscopic’ images of guns being fired. Like this one:

Now, what do I mean ‘natural stereoscopic’ images? Well, this is pretty cool itself. Here’s a reference link & explanation from the Kuulapaa site:

Help: How to Free-View the Stereo Pairs

Each stereo view consists of two images, one for each eye. Free viewing is the technique that will allow you to direct each of these images separately and simultaneously into each eye. Once that happens, you are said to have “fused” the pair of images into a stereo view.

At the bottom of this page a stereo pair of images is loading with which you can practice. All the stereo pairs shown on this site are in the “cross-eyed” format (my apologies to all the “wall-eyed” people). That means that the first (leftmost) image is for your right eye and the right image is for your left eye.

There are then a series of practice image to show what he means and give you a chance to develop this viewing skill. It works fairly well for me, but does tire my eye muscles fairly quickly. Give it a try and see how you do.

Jim Downey

*Couldn’t resist. Lyrics here.

 

February 1, 2014 Posted by | .44 Magnum, Discussion., Links | , , , , , , , , , , , , , , , , | 1 Comment

Rimfire Roundtable

Well, it’s too damned cold in most of the country to go out to the range, so if you’d like to see hear why I didn’t stay in radio as a career, and maybe enjoy some good discussion about rimfire cartridges and guns, take a listen to this new podcast:

Episode #26 Rimfire Roundtable #1

On this show I was lucky enough to round up three guys uniquely qualified for the first ever Rimfire Roundtable. We discuss what we would like to see come from the firearms industry regarding rimfire, better supplies of ammunition aside. I hope you enjoy our discussion and let us know your ideas too.

It’s about an hour long, all told, and in spite of my participation fairly interesting/informative. Check it out if you have some listening time!

 

Jim Downey

January 7, 2014 Posted by | .22, .22WMR, Anecdotes, Discussion., Links | , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

Wait … it’s 2014?? How did THAT happen?

2013 was a busy year for BBTI.

We did the .22Mag tests. We did the 9mm Glock Tests. I got my .460 Rowland conversion up and running. And I found some really fun .44Mag +P+ loads, then figured out a simple hack so that they would feed reliably in my lever gun. Like I said, a busy year.

And we couldn’t have done it without help. Of several types. To see the list of those donors who have helped offset some of our operating costs, pop over to the BBTI site. And here’s a list of the top-10 referring sites (excluding search engines and Wikipedia):

  1. thefiringline.com
  2. defensivecarry.com
  3. guns.com
  4. thefirearmblog.com
  5. ar15.com
  6. thetruthaboutguns.com
  7. survivalistboards.com
  8. glocktalk.com
  9. reddit.com
  10. rimfirecentral.com

Altogether, we had 243,230 visitors to the BBTI website, and some 12,000+ views of this blog. Since we’ve gone through several iterations of the site over the last five years, it’s hard to say exactly how many visitors or pageviews or hits we’ve had in total — but it’s more than we ever really expected. Thanks, everyone.

And particular thanks to my Good Lady Wife, who has done all the webwork and most of the number crunching over the years.

We don’t currently have any concrete plans for new tests in 2014. But who knows? Keep an eye here and on our Facebook page for news.

Happy New Year, everyone!

 

Jim Downey

 

January 1, 2014 Posted by | .22WMR, .44 Magnum, .460 Rowland, 9mm Luger (9x19), Anecdotes, Data, Discussion., Links | , , , , , , , , , , , , , , , , , | 2 Comments

Happy Thanksgivuk … er, I mean Birthday!

OK, first: Happy Thanksgiving to all my fellow Americans. And Happy Hanukkah to all who observe it!

But most of all,

Happy Birthday to BBTI!

Yeah, it’s our fifth birthday. We officially launched the site on Thanksgiving in 2008.  And it’s been a fun romp since then. We’ve gone through many different iterations on the site, adding in more calibers/cartridges, doing the big cylinder gap test, tweaking this and changing that. We’ve shot something on the order of 22,000 – 23,000 rounds. We’ve had something in excess of 20 million hits to the site. We’ve invested more than $50,000 and untold hundreds of hours of labor. And we’ve become pretty much the default resource for anyone who has needed (or just wondered about) data pertaining to handgun ammunition performance over barrel length. Like I said, it’s been fun! Thanks for helping to make it so!

And since it is our birthday, it’s time for a gift in the form of a whole new section to the BBTI website:

Polygonal v. Traditional L&G Rifling (“Glock tests”)

From that page:

For years people have wondered about the effects of the different styles of rifling, and whether one or the other would offer specific advantages for accuracy or velocity from a given cartridge.  But since many different factors can have an effect on both accuracy and velocity, these discussions have largely remained anecdotal.  We decided to see whether we could generate data as to performance differences between the two styles of rifling as concerns bullet velocity, using our standard chop-test techniques.  The data on this page is the result of those tests.

Check it out when you get a chance! And thanks again to all who have shared links to our site, who have sent us emails, who have contributed to help offset our costs — you folks have made our success possible, and it is very much appreciated.

 

Jim Downey

PS: as a personal thanks as well, I have made both my first novel and our care-giving memoir available for free download for today and tomorrow (Nov. 28th & 29th).

November 28, 2013 Posted by | 9mm Luger (9x19), Anecdotes, Data, Discussion., Links | , , , , , , , , , , , , , , , , , | 1 Comment

With charts! Graphs! Slo-mo!

John Ervin at Brass Fetcher Ballistic Testing has put together another great video presentation, showing in several ways how Jacketed Hollow Point (JHP) ammo performs in comparison to Full Metal Jacket (FMJ) ammo for 9 different handgun cartridges. It’s long (22 minutes), but very nicely documents just exactly how the two different bullet styles behave at handgun velocities. Here’s the video:

 

 

The cartridges covered are .22 LR, .25 ACP, .32 ACP, .380 ACP, 9mm Makarov (9×18), 9mm Police (Ultra), .38 Special, 9mm Luger (9×19), and .45 ACP.  His data and presentation makes a great companion to our own data, and I really recommend that you set aside the time to watch the video at your earliest convenience.

 

Jim Downey

October 22, 2013 Posted by | .22, .25 ACP, .32 ACP, .38 Special, .380 ACP, .45 ACP, 9mm Luger (9x19), 9mm Mak, 9mm Ultra, Data, Discussion., Links | , , , , , , , , , , , , , , , , , , , , , | Leave a comment

M1 .30 carbine performance.

Got another nice email with a video link from John Ervin at Brass Fetcher Ballistic Testing, this time covering the performance of the venerable M1 Carbine .30 cal cartridge. From John:

Despite its handsome wood furniture and vaguely military-type appearance, the M1 Carbine is an effective firearm for self-defense and small game hunting.  Hornady makes ‘Critical Defense’ ammunition for it now and Federal continues to make its excellent 110gr SP, so good ammunition choices are available for M1 Carbine owners.

The M1 Carbine is excellent for its low recoil, small mechanical sight offset and cartridge that is sufficient in lethality to repulse human attackers (when using good soft point ammunition) at distance.

And here’s the video so you can see for yourself:

 

 

I’ll leave it at that for now … I have a lot to do this week to get ready for our 9mm “Glock Tests” this coming weekend. Yup, those are finally happening. I’ll post some preliminary thoughts/results probably this weekend or the first of next week, with full info to come after we have a chance to crunch the numbers a bit.

 

Jim Downey

October 1, 2013 Posted by | .30 carbine, 9mm Luger (9x19), Data, Discussion., Links | , , , , , , , , , , , , , | Leave a comment

It’s like flinging thunderbolts.

You may remember that I have a small bit of an obsession with the .460 Rowland cartridge.  Ever since we tested it for BBTI, I’ve wanted one. As I noted in one of those articles:

I said it before and I’ll repeat it here: if you carry a .45, you should instead be carrying a .460 Rowland.

 

So, early this year I put in an order for a .460 Rowland conversion kit for a new Gen 4 Glock 21.

I’m planning on doing a full formal review of the kit and the resultant gun, but I thought I’d share some of my experience so far. Why “so far”? Well, because I haven’t worked out all the minor kinks yet.

OK, first thing: it didn’t just take the 3 weeks for delivery which was promised. It wasn’t even 3 months. It was almost six months. And a buddy of mine who ordered his before I ordered mine still hasn’t gotten his. So, there’s that.

Second, and part of the reason for the delay, I didn’t receive a new barrel which was marked .460 Rowland. Rather, I got what looked like a standard Wolff .45 barrel. But it had indeed been rechambered to handle the .460 Rowland cartridge. Before I received the kit I got an email advising me of this problem, and I figured I could just roll with it. This is what I got in the kit:

.460 Rowland Conversion Kit.

.460 Rowland Conversion Kit.

 

Going clockwise from the top: That’s the threaded barrel, a screw-on compensator, spring assembly adapter, small serving of red loc-tite, and the heavy spring assembly (which is actually the Gen 3 design, but with the adapter works just fine in my Gen 4).

As advertised by .460 Rowland, the conversion takes like 30 seconds. If you can field strip your Glock, you can do the conversion. I’ve opted for using blue loc-tite rather than red, since it still works well but allows me to remove the compensator easily if I need to.

How does it work? Well, I’ve taken it out to the range several times now, shooting both factory rounds as well as my own reloads. Doing some informal chrono tests, I have gotten exactly the kind of performance promised and expected. The Buffalo Bore 230gr JHP were right at 1300 fps. 200gr RNFP reloads were at 1380 fps, and 185gr XTP (JHP) reloads were at 1410 fps. And those reloads are actually fairly mild — just 12.5gr of Longshot powder — based on what data I’ve seen, I could probably push that to 13.5gr without any risk. (Don’t consider this an endorsement — do your own research, and work up your own loads using published data and standard safety practices.)

Shooting the .460 loads out of the Glock is like shooting a .44 magnum (which I have a fair amount of practice with), but having 13 rounds on tap. Seriously, it’s like flinging thunderbolts with each shot. And the recoil is surprisingly manageable, though I’m not someone who is very recoil shy.

So, why did I say I was still working out the kinks?

Well, there’s a problem with the magazines. Here’s what happened after the first outing:

Glock 21 magazine

Glock 21 magazine

 

Look closely on the left side of that magazine, and you’ll see that there’s a tab which has been torn a bit loose and pushed forward. That’s from the force of the .460 cartridges slamming forward. At about this point the magazine would no longer release or insert smoothly. That was after my first outing, with about 60 .460 Rowland shots fired. And actually, I damaged two magazines to that extent with those 60 rounds.

So after that first outing, I took a Dremel tool to the magazines and cut away about 1/8″ of material, and flattened the whole face back into position. Today I took those two magazines back out to the range, and ran about another 50 rounds through the gun using the two of them. Here’s one of them after today’s outing, next to a new unaltered magazine:

Two Glock 21 magazines.

Two Glock 21 magazines.

 

More problems. This time, the little metal tab snapped off, as well as distorting the face of magazine again. Clearly, I need to sort out how to fix this.

Two other things I want to mention. One, I tried shooting standard .45ACP cartridges out of the .460 Rowland conversion. They work wonderfully. Seriously, there’s almost no recoil, the gun cycles just fine (with my mild reloads as well as factory +P self defense ammo), and there’s no accuracy loss that I could determine casually shooting the gun. So, that’s a plus.

But the other thing? Heh — take a look at what happened with my front site today:

Glock 21

Glock 21

Yeah, it really shouldn’t be facing that way, nor sticking up quite so much. But I can fix that easily enough.

If you have thoughts on how I can correct the magazine problem, I’d love to hear ‘em.

 

Jim Downey

September 23, 2013 Posted by | .45 ACP, .460 Rowland, Anecdotes, Discussion. | , , , , , , , , , , , , , , , , | 7 Comments

Buckshot effectiveness at 50 yard range.

John Ervin at Brass Fetcher Ballistic Testing is a friend, and I have a lot of respect for his research. We talked about this project a while back, figuring out how to get reliable data, and it’s cool to see the results.

The whole vid is worth watching, but if you’re looking for just the results, skip to about 7:00. For his conclusions based on the results (with some excellent advice), skip to about 9:30.

Bottom line: use at least 00 buckshot, if you want it to be effective out to 50 yards.  Know your gun, and test it to see what loads perform best at that distance.

 

Jim Downey

September 15, 2013 Posted by | Data, Discussion., Links, Shotgun ballistics | , , , , , , , , , , , , | 1 Comment

Just take a little off the sides, leave the top alone.

So, yesterday was our best day ever for this blog, doing 50% more traffic than any previous day. Why? Well, thanks to a link from The Firearm Blog about my experiments to alter the Buffalo Bore 340gr .44mag loads I’ve written about recently. So I wanted to say thanks to Steve over there, and to all his readers.

And I also wanted to report how the rounds behaved after a trip to the range this morning. I think pictures tell the story just fine. Here’s the first one:

20130829_105140

That’s a 3″ circle, just for reference. Those are three shots, fired from a sitting position at 50 yards (well, paces, so something pretty close to 50 yards). That’s with the standard, unaltered, 340gr rounds from my Winchester 94AE which has the standard iron sights. I wasn’t trying for super accuracy, just the sort of quick sight and shoot you’d do when hunting at that range. It may be worth noting that I had to hand-feed each round into the chamber of the gun, since these unaltered cartridges will not feed from the tube magazine. If you look close, you’ll see that I marked through each hole with a blue Sharpie.

Here’s the second picture:

20130829_105528

Exact same parameters as the first pic, but this time with three rounds which had been shaved as discussed in the previous posts. And since these rounds will reliably feed from the tube magazine, they were shot then the gun was cycled and then the next shot taken in fairly quick sequence. For clarity, I marked through the second set with a red Sharpie.

My conclusion? They’re as accurate as the unaltered cartridges. Which is to say, within the limits of my ability using them like that. With a good shooting rest and a scope you might be able to tell a difference, particularly at greater range. But for what I wanted them for, they’re entirely suitable. YMMV.

 

Jim Downey

August 29, 2013 Posted by | .44 Magnum, Anecdotes, Data, Discussion., Links | , , , , , , , , , , , , | Leave a comment

A review …

A number of people have noticed that our .22 magnum data contains one very odd discrepancy: the Rossi Circuit Judge we used in the ‘real world’ portion of the tests performed really poorly, in terms of bullet velocity for all the ammo tested. If you’re curious why this is, go check out my review of the gun over at Guns.com:

The Rossi Circuit Judge .22 Convertible: Stylish, fun, cool, but there’s one drawback…

 

Jim Downey

June 24, 2013 Posted by | .22WMR, Anecdotes, Data, Discussion., Links | , , , , , , , , , , , | Leave a comment

.22 Magnum article.

My .22 Magnum article looking at our data and my conclusions is now up over on Guns.com. Here’s an excerpt:

Bottom line

For me, the take-away lesson from these tests is that the .22 Magnum is a cartridge that is best served out of rifle barrel. At the high end we were seeing velocities that were about 50 percent greater than what you’d get out of a similar weight bullet from a .22 LR. In terms of muzzle energy, there’s an even bigger difference: 100 percent or more power in the .22 Magnum over the .22 LR.

But when you compare the two on the low end, out of very short barrels, there’s very little if any difference: about 10 percent more velocity, perhaps 15 percent more power. What you do notice on the low end is a lot more muzzle flash from the .22 Magnum over .22 LR.

While you do see a real drop-off in velocity for the other magnums from very short barrels, they tend to start at a much higher level. Compare the .357 Magnum to the .38 Special, for example, where the velocity difference is 30 to 40 percent out of a 2-inch barrel for similar weight bullets, with a muzzle energy difference approaching 100 percent. Sure, you get a lot of noise and flash out of a .357 snubbie, but you also gain a lot of power over a .38.

Go check out the whole thing!

Jim Downey

June 5, 2013 Posted by | .22, .22WMR, .357 Magnum, .38 Special, Data, Discussion., Links | , , , , , , , , , , | 1 Comment

Ammo shortage? What ammo shortage??

Oh — THAT — ammo shortage.

Yeah, the beginning of January I wrote that we were finally moving forward with the testing of polygonal vs. traditional rifling; the so-called “Glock Tests“, and outlined how we were planning on conducting a bit of an experiment in asking for suggested ammo loads to include in the tests, and then seeing what kind of support there was for a slate of different choices by allowing pledges to help purchase ammo.

But, as someone who wrote me put it: where did we think we were going to *find* any such ammo?

Initially, I thought that the shortage we were seeing would be a fairly temporary problem, and that by the time spring rolled around we’d be able to locate sufficient quantities for our testing (we need about 350 rounds of each type).

Yeah, so much for that idea. Now you know why I don’t play the stock market or bet on races.

The ammo shortage has just continued to deepen. It’s to the point where people are having a hard time finding enough of any kind of ammo just to keep in practice with a trip to the range once or twice a month.  I’m damned glad I reload my practice ammo, and have a decent store of most components.

But that doesn’t do a damned thing for our testing. The whole idea is to test factory ammo, not some cobbled-together handload version of factory ammo.

So we’re putting off the “Glock Tests” again, until the situation gets better. Keep an eye here and elsewhere for news about when this will change.

One good bit of news, however: we already had a decent selection and sufficient quantity of each ammo type to do the .22WMR (.22Magnum) tests.  So we’re going to go ahead and do that sequence of tests here this spring — sometime soon!

Sorry for the bad news, everyone — really. These tests have been delayed several times for one (good) reason or another, and we’re just as frustrated by that as everyone else.  But when ammo supplies start to become more available, we’ll be sure to try and get them done as soon as we can.

Cheers!

Jim Downey

March 4, 2013 Posted by | .22WMR, .45 ACP, 9mm Luger (9x19), Anecdotes, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , | Leave a comment

Now, about those “Glock” tests…

As mentioned previously, for some time we’ve been planning on doing a series of inch-by-inch chop tests on the Glock-style polygonal barrels  (Glock was unable to supply 18″ barrels, so we’ll be using 6 grove poly and 6 land traditional barrels from Lothar Walther).  We’ve run into a number of unexpected delays, but now have the barrels we need, and are planning on doing the series of tests sometime later this year, hopefully in spring/early summer. For testing purposes, we’ll be conducting traditional ‘land & groove’ barrels in the same calibers at the same time, so that we have direct head-to-head comparisons. Because we’re expecting a fairly subtle difference in performance, we’re going to do 10 (ten) shots for each inch of barrel for both style barrels. And to keep the scope of the project manageable, we’re only going to test two cartridges/calibers: 9mm (9×19) and .45 ACP.

In order to do the tests this way, we’ll need a minimum of 340 rounds of each ammo to test. Add in “real world guns” and allowing for errors/glitches which mean extra shots, we’re planning on getting 400 rounds of each ammo to be tested. Figure an average of about $1 per round for premium self-defense ammunition, and we’re looking at about $400 for each ammo selected for testing. There are some specific ammunition types/loads we’ve tested previously that we want to revisit for comparison purposes, but our selection is hardly comprehensive — time and money are limited.

So we’d like to try an experiment: do Kickstarter-style crowdfunding to see what ammunition types/loads people want to have us test. This will allow two things:

  1. To let people help support the project by offsetting our costs.
  2. To help us find new ammunition types/loads.

Now, Kickstarter itself isn’t firearm-friendly. And that’s OK — we can do this on our own, just using our own site. What we’ll do is put up a list of different ammo types/loads, and solicit donations targeted for each during a specific time frame. When pledges are made, we’ll keep a running tally total for each ammo, and once it crosses a certain threshold, then that specific type/load will be added to our testing list.

But first we need to create our list of ammo. So, for the next two weeks, either add a comment to this blog post or send an email to info@ballisticsbytheinch.com with one specific 9mm ammunition type/load you would like to see us test. Please, just one type/load per comment or email, and just five or six such entries per person. I’m going to have to collate these myself, so help make it a little easier on me. Just sending in a selected ammo doesn’t obligate you to support that ammo with $ in the second phase of this test, but it’s probably a good idea to only recommend ammo you would be willing to actually support, and ones you think you can get others to support. And remember, keep your recommendations limited to factory mass-produced ammo; handloads or artisanal ammo which the average person doesn’t have access to will not be selected for inclusion in the tests. Also: we’re only accepting recommendations and donations from individuals, not ammo manufacturers.

You can see all the 9mm ammo we’ve tested previously here: 9mm Luger Results.

As I said, this is an experiment. If it works for selecting 9mm ammo to test, we may extend it to the .45 ACP tests, and then see about using a similar approach for other testing. We hope that this will be a way we can expand our research and make it more responsive to what data the firearms-enthusiast community wants to see. You can help by sending in your suggestions, but in also spreading the word on the different forums/blogs where our data may be used.

Thanks, everyone, for your ongoing interest and support!

Jim Downey

January 4, 2013 Posted by | .45 ACP, 9mm Luger (9x19), Data, Discussion. | , , , , , , , , , , | 3 Comments

And once again…

…I am reminded of how happy I am to not have to deal with the public day in and day out.

As I said two months ago:

People really will always find something to bitch about, won’t they? Even if it is free & unencumbered research data that they can’t get elsewhere.

This time I got a complaint from someone about our having excluded a particular make of handgun. No “Hey, thanks for the data, I wonder why you haven’t tested This Brand?” Or “I love the site, but is there a reason why you’ve not included This Brand?” Just an email with the header “WHY NO GLOCKS TESTED?” Yeah, all caps. Nothing else other than the question repeated in the body.

I actually get some variation of this  question just about every week. Let me rephrase that: at least every week. Which is why that question is at the top of the FAQ on the BBTI site.

I responded, as I usually do, with that link and some variation of: “we didn’t include them because we hate them” (which is joking off of what the FAQ says). Usually this takes care of the issue.

But sometimes people either don’t go look at the FAQ, or are too dense/sarcasm-impaired to “get” my response. That was the case with the current querent. After a couple more exchanged emails I finally convinced him that we don’t actually hate Glocks.

But the truth is, we *have* intentionally excluded Glocks so far. As I told my querent in my final email:

There are a lot of different factors which go into the selection of the guns we include in our tests. Glocks have a different barrel structure, so comparing them with the ‘standard’ rifling tends to skew results. For this reason we’ve so far avoided including them.

I say “so far” because we’re presently in the process of finalizing a test sequence where we do the formal inch-by-inch chop tests on Glock polygonal barrels. It’s taken us two years to be able to get the necessary 18″ blanks to do this properly. Having that data will allow us to do head-to-head comparisons with the ‘standard’ rifling results, and so give everyone data which actually is useful rather than just anecdotal. And yes, as part of that sequence we will be testing actual Glocks in different calibers and with different barrel lengths. We hope to be able to conduct these tests yet this fall, but are waiting on the gunsmithing work to be done.

This isn’t actually “news” – I hinted at it in June on the BBTI Facebook page (which you should “Like” if you’re on FB, so you see these things sooner), but it is the first I’ve mentioned it here or on any forums.

Anyway, yeah, I’m glad I don’t have to deal with the public on a daily basis any longer. My blood pressure problems would be a lot worse than they actually are.

Jim Downey

August 29, 2012 Posted by | .45 ACP, 9mm Luger (9x19), Data, Discussion., General Procedures, Links | , , , , , , , , , | 2 Comments

Great new resource.

The folks over at LuckyGunner.com have started a blog, and the first post up is some really solid data from their testing of the differences between 5.56 NATO and .223 Remmington. From the post:

The differences between .223 Remington and 5.56mm NATO have been hashed out many times on the internet. Unfortunately, many of the “facts” that are often thrown around are simply what someone has heard from someone else, leading to a lot of misinformation being accepted as gospel.

In order to create this article, I temporarily set aside all of my previous knowledge and opinions while several months’ worth of new research and experimentation on the topic was undertaken. In addition, extensive discussions with gunsmiths, ballisticians, and laboratory technicians were conducted.

My findings, and the opinions of many experts in the industry who deal with the topic every day, were not exactly what some might expect. In fact, many of them had already discovered what I am reporting, although my research was conducted independently.

It’s a long, and really solid piece of research. If this is going to be typical of their stuff (and I think it will be — I know one of the guys involved with this, and respect his intelligence & commitment a lot), then this will be one hell of a great resource for those of us who are looking for good information that we can trust.

Check it out!

Jim Downey

June 22, 2012 Posted by | .223, Data, Discussion., Links | , , , , , , | Leave a comment

June? Already?

Yeah, seems to be. So here’s the numbers & info for the last month, plus a little look ahead:

We had 19,937 visitors to the BBTI homepage in May. We’ve added a number of additional review links to the list of Real World Guns. Followers for both Twitter and Facebook have also seen a nice uptick this last month.

Back in March I reported on how Google Adsense had screwed us over. Well, after looking at a number of options and being realistic about what kind of revenue advertising could generate, we’ve pretty much decided to just give up on advertising — with one small exception for now: you’ll note that some of the BBTI pages have a small ad promotion my novel. It is proving to be very popular, and the reviews for it have been quite positive — check it out. Of course, we’re still happy to accept donations to help offset expenses associated with BBTI — and thanks to those who have donated!

Happy & safe shooting, everyone!

Jim Downey

June 1, 2012 Posted by | Anecdotes, Discussion., Links | , , , , , , , , , , , , | Leave a comment

…bring May flowers.

Well – I see that I didn’t post stats last month for March. Sorry about that – a combination of being busy promoting my novel as well as getting together with some of the other BBTI guys to do some fun shooting (and to try out a .460 Rowland conversion kit for a Glock 21!).

So, first things first: March had a total of 21,499 visitors, and April had 19,918 visitors. Just a bit of a slow period there.

Next, remember that we’re now linking from the BBTI page on Real World Guns to reviews of said guns I’ve written for Guns.com. There are usually a couple new each week, so check back often!

And here is the first of some additional reviews from my shooting expedition the beginning of April: Wise Lite Arms Sterling 9mm. Coming weeks should see more than a dozen other reviews of handguns and PCCs (pistol caliber carbines).

A quick note that things with my novel have been going great, and so far some 14,000 people have downloaded the Kindle edition. If you enjoy my reviews and articles, then you may want to check out the book – it’s been getting a lot of really good discussion and reviews.

May 1, 2012 Posted by | .460 Rowland, 9mm Luger (9x19), Anecdotes, Links | , , , , , , , , , , , | Leave a comment

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