Ballistics by the inch

Join the party.

All along, we’ve said that if someone wanted to take the time, trouble, and expense to do some additional research along the lines of our protocols, that we’d be happy to include their data on our site. This is particularly true if it helped expand the selection of “real world guns” associated with the data for a given caliber/cartridge. Well, for the first time someone has expressed an interest in doing just that, prompting us to come up with an outline of what standards we feel are required for making sure it relates to our previous tests.

The biggest problem is that ammo manufacturers may, and do, change the performance of their products from time to time. This is why we have on occasion revisited certain cartridges, doing full formal chop tests in order to check how specific lines of ammo have changed. That gives us a benchmark to compare other ammo after a period of several years have passed, and shows how new tests relate to the old data.

But without going to such an extent, how can we be reasonably sure that new data collected by others using their own firearms is useful in comparison to our published data?

After some discussion, we feel that so long as any new testing includes three or more of the specific types of ammo (same manufacturer, same bullet weight & design) we had tested previously, then that will give enough of a benchmark for fair comparison. (Obviously, in instances where we didn’t test that many different types of ammo in a given cartridge, adjustments would need to be made). With that in mind, here are the protocols we would require in order to include new data on our site (with full credit to the persons conducting the tests, of course):

  1. Full description and images of the test platform (firearm) used in the tests. This must specify the make, model number, barrel length, and condition of the firearm. Ideally, it will also include the age of the firearm.
  2. That a good commercial chronograph be used. Brand isn’t critical — there seems to be sufficient consistency between different models that this isn’t a concern. However, the brand and model should be noted.
  3. Chronographs must be positioned approximately 15 feet in front of the muzzle of the firearm used to test the ammo. This is what we started with in our tests, and have maintained as our standard through all the tests.
  4. That five or six data points be collected for each type of ammo tested. This can be done the way we did it, shooting three shots through two different chronographs, or by shooting six shots through one chronograph.
  5. All data must be documented with images of the raw data sheets. Feel free to use the same template we used in our tests, or come up with your own.
  6. Images of each actual box of ammo used in the test must be provided, which show the brand, caliber/cartridge, and bullet weight. Also including manufacturer’s lot number would be preferred, but isn’t always possible.
  7. A note about weather conditions at the time of the test and approximate elevation of the test site above sea level should be included.

We hope that this will allow others to help contribute to our published data, while still maintaining confidence in the *value* of that data. Please, if you are interested in conducting your own tests, contact us in advance just so we can go over any questions.

 

Jim Downey

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September 9, 2016 Posted by | .22, .223, .22WMR, .25 ACP, .30 carbine, .32 ACP, .32 H&R, .327 Federal Magnum, .357 Magnum, .357 SIG, .38 Special, .380 ACP, .40 S&W, .41 Magnum, .44 Magnum, .44 Special, .45 ACP, .45 Colt, .45 Super, .450 SMC, .460 Rowland, 10mm, 9mm Luger (9x19), 9mm Mak, 9mm Ultra, Anecdotes, Data, Discussion., General Procedures | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

‘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

That’s … unexpected.

Checking this morning’s stats (which I do pretty much every morning, over my first cup of coffee, just out of idle curiosity), I saw that there was an incoming link … from the Washington Post.

???

So I followed the link back, read the article, and didn’t see anything in it about BBTI. However, given the topic of the article (actually, it’s an editorial), I figured that I’d find the incoming link in the comments. And here it is:

enzo11

3/13/2015 3:58 PM CST [Edited]

There are actually many very short barreled pistols ( 7 inch, on down to Derringer-sized under-3 inch) available chambered for the .223 round.

But what this idiot of an author forgets is basic physics : the shorter the barrel, the lower the muzzle velocity. The lower the muzzle velocity, the less penetrating power the bullet has – by a large factor ( the energy is partially determined by the square of the velocity).

For a chart on muzzle velocity for different barrel lengths:

http://www.ballisticsbytheinch.com/223rifle.html

For what that does to the available energy:

http://www.ballisticsbytheinch.com/2011graphs+/223…

 

OK, BBTI wasn’t actually cited by the Washington Post. But it’s still amusing.

 

Jim Downey

March 15, 2015 Posted by | .223, Data, Discussion., Links | , , , , , , , , , | 1 Comment

Six shooter.

Well, well, well, BBTI made it to six years of shooting fun and research!

Yup, six years ago today we posted the first iteration of Ballistics By The Inch, and included data for 13 different handgun cartridges. Since then we’ve continued to expand on that original research, including some extensive testing on how much of an effect the cylinder gap on revolvers has, what performance differences you can expect from polygonal over traditional land & groove rifling, and added another 9 cartridges, as well as going back and including a very large selection of real world guns in all the different cartridges. This blog has had 100,000+ visitors and the BBTI site itself has had something like 25 – 30 million visits (the number is vague because of changes in hosting and record-keeping over time).

We’ve had an impact. I’ve seen incoming links from all around the world, in languages I didn’t even recognize. There’s probably not a single firearms discussion group/blog/site out there which hasn’t mentioned us at some point, and our data is regularly cited in discussions about the trade-offs you make in selecting one cartridge or barrel length over another. I’ve answered countless emails asking about specific points in our data, and have been warmly thanked in return for the work we’ve done. And on more than a few occasions people have pointed out corrections which need to be made, or offered suggestions on how we could improve the site, sometimes providing the results from their own crunching of our data.

When we started, it was fairly unusual to see much solid information on ammo boxes about how the ammunition performed in actual testing. Now that information is common, and expected. Manufacturer websites regularly specify real performance data along with what kind of gun was used for that testing. And the data provided has gotten a lot more … reliable, let’s say. We’ve been contacted by both ammo and firearms manufacturers, who have asked if they can link to our data to support their claims of performance — the answer is always “yes” so long as they make it clear that our data is public and not an endorsement of their product. And we’ve never taken a dime from any of those companies, so we can keep our data unbiased.

And we’re not done. We have specific plans in the works to test at least one more new cartridge (and possibly revisit an old favorite) in 2015. I try to regularly post to the blog additional informal research, as well as sharing some fun shooting and firearms trials/reviews. There’s already been one firearms-related patent issued to a member of the BBTI team, and we’ll likely see several more to come. Because we’re curious guys, and want to share our discoveries and ideas with the world.

So, onward and upward, as the saying goes. 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.

 

Jim Downey

November 28, 2014 Posted by | .22, .223, .22WMR, .25 ACP, .30 carbine, .32 ACP, .32 H&R, .327 Federal Magnum, .357 Magnum, .357 SIG, .38 Special, .380 ACP, .40 S&W, .41 Magnum, .44 Magnum, .44 Special, .45 ACP, .45 Colt, .460 Rowland, 10mm, 6.5 Swedish, 9mm Luger (9x19), 9mm Mak, 9mm Ultra, Anecdotes, Data, Discussion., General Procedures, Links, Shotgun ballistics | , , , , , , , , , , , , , , , , , , , , , | 1 Comment

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

It’s Up!

The new Ballistics By The Inch site is now up and running! Bigger, Faster, And with More DATA! Take a look, spread the word, let us know if there are any glitches or problems.

Jim Downey

December 1, 2011 Posted by | .22, .223, .25 ACP, .32 ACP, .32 H&R, .327 Federal Magnum, .357 Magnum, .357 SIG, .38 Special, .380 ACP, .40 S&W, .41 Magnum, .44 Magnum, .44 Special, .45 ACP, .45 Colt, .460 Rowland, 10mm, 9mm Luger (9x19), 9mm Mak, 9mm Ultra, Anecdotes, Data, Discussion., General Procedures, Links | , , , , | Leave a comment

8 million hits in the naked city.

Hey everyone –

Long time, no posts. Sorry about that. The summer and fall were filled with a lot of different high-intensity projects. But I have several things to share this morning…

One, we broke 8 million hits to the BBTI website about a week ago. That’s in just under 3 years time. Congrats to one an all, and thanks.

Two, barring unforeseen complications and general catastrophe, *tomorrow* we’ll launch the completely revamped BBTI. It will contain all the data that you know and love, but there will be a lot more. Like:

  • Data on our .22 chop tests this summer – 10 different ammos, and also 20 ‘real world’ .22 guns.
  • Data on our .460 Rowland chop tests last spring – an impressive cartridge!
  • Data on our .223 chop tests this last spring – Yup, it is definitely a rifle cartridge.
  • Data on our HUGE ‘Cylinder Gap’ tests this last spring, involving over 6,000 rounds fired. Some very interesting results.
  • Revised means of navigating the site, to reflect the way people have been using it, in order to make it faster and easier.
  • A comprehensive list of the 99 different ‘real world’ guns we’ve tested so far.
  • A bunch of new graphs and charts and data sets for your inner ballistic geek.
  • Some new links and other goodies.

So, get the champagne on ice, find your party hats – there’s gonna be a celebration tomorrow as we launch this new ship!

Jim Downey

November 30, 2011 Posted by | .22, .223, .460 Rowland, Data, Discussion., General Procedures, Links | , , , | Leave a comment