April 13th, 2014

Field Skills: Reading the Wind When Hunting

On LongRangeHunting.com, you’ll find a good article by Shawn Carlock about wind reading. Shawn is a veteran law enforcement marksman and a past USPSA national precision rifle champion. Shawn offers good advice on how to estimate wind speeds and directions using a multitude of available indicators — not just your wind gauge: “Use anything at your disposal to accurately estimate the wind’s velocity. I keep and use a Kestrel for reading conditions….The Kestrel is very accurate but will only tell you what the conditions are where you are standing. I practice by looking at grass, brush, trees, dust, wind flags, mirage, rain, fog and anything else that will give me info on velocity and then estimate the speed.”

Shawn also explains how terrain features can cause vertical wind effects. A hunter on a hilltop must account for bullet rise if there is a headwind blowing up the slope. Many shooters consider wind in only one plane — the horizontal. In fact wind has vertical components, both up and down. If you have piloted a small aircraft you know how important vertical wind vectors can be. Match shooters will also experience vertical rise when there is a strong tailwind blowing over an up-sloping berm ahead of the target emplacements. Overall, Shawn concludes: “The more time you spend studying the wind and its effect over varying terrain the more successful you will be as a long-range shooter and hunter.”

Permalink - Articles, Hunting/Varminting, Shooting Skills 1 Comment »
March 24th, 2014

Six Shooting Tips from Bryan Litz

If you only know Bryan Litz from his Applied Ballistics Books and DVDs, you may not realize that this guy is a great marksman (along with being an actual rocket scientist). This guy can shoot. At the recent Berger Southwest Nationals (SWN), Bryan took top honors among all sling shooters — and he managed to do that while performing many other important match duties. The pay-off for Bryan was getting his name on a really cool “ghost dancer” perpetual trophy. Litz joked: “With what the wind gods can do at shooting matches, it makes sense to have a trophy that puts you in touch with the spirit world.”

Bryan Litz Tips

This is actually the second time Litz has finished first in Sling class at the Southwest Nationals. After his impressive win, we asked Bryan if he had any advice for other long-range competitors. First Bryan provided three tips concerning Ballistics, his special area of expertise. Next Bryan offered three more general tips about long-range competition — how to analyze your shooting, how to choose your ‘wind strategy’, and how to avoid the most costly mistakes, i.e. how to avoid the “train-wrecks”.

Bryan Litz Tips

Litz Ballistics Tips

Ballistics TIP ONE. If you’re having trouble getting your ballistic software to match actual drops, you need to look at a number of possible reasons. Here are some common issues that can cause problems.

Click Values Are Not Exact. Scopes and iron sights don’t always produce accurate adjustments. In other words, if your ballistics program predicts 30 MOA of drop, and you dial 30 MOA but hit low, it might be that your sight actually only moved 28 MOA (for example). To see if your sight is adjusting accurately, shoot a tall target at 100 yards and measure group separation when dialing your sight.

Barometric vs. Station Pressure. This is a commonly misunderstood input to ballistics programs. You can avoid this pitfall by remembering the following: station pressure is the actual measured pressure at your location, and you don’t need to tell the program your altitude when using station pressure. Barometric pressure is corrected for sea level. If you’re using barometric pressure, you also have to input your altitude.

Muzzle Velocity. Chronographs are not always as accurate as shooters think they are — your true MV may be off by 10-20 fps (or more). If your drop is different than predicted at long range, it might be because your muzzle velocity input is wrong.

Mixing Up BC (G1 vs. G7). Knowledgeable long range shooters know that the G7 standard is a more representative standard for modern LR bullets. However, using G7 BCs isn’t just a matter of clicking the ‘G7′ option in the program. The numeric value of the BC is different for G1 and G7. For example, the G1 BC of the Berger 155.5 grain Fullbore bullet is .464 but the G7 BC is .237. If you were to enter .464 but click on G7, the results would be way off.

Ballistics TIP TWO. A properly installed level is absolutely essential for long range shooting. Without a good level reference, your long range wind zero will be off due to minor canting of the rifle from side to side. You can verify that your level is installed correctly on a 100-yard ‘tall target’. Draw a plumb line straight up the target and verify that your groups track straight up this line as you go up in elevation.

Ballistics TIP THREE. If your long range ballistic predictions aren’t tracking, always come back and verify your 100-yard zero. Sometimes a simple zero shift can be misconstrued as errors in long range ballistics predictions.

Bryan Litz Tips

Litz Competition Shooting Tips

Competition TIP ONE. Improving your scores in long range competition is a constant process of self-assessment. After each match, carefully analyze how you lost points and make a plan to improve. Beginning shooters will lose a lot of points to fundamental things like sight alignment and trigger control. Veteran shooters will lose far fewer points to a smaller list of mistakes. At every step along the way, always ask yourself why you’re losing points and address the issues. Sometimes the weak links that you need to work on aren’t your favorite thing to do, and success will take work in these areas as well.

Competition TIP TWO. Select your wind shooting strategy carefully. For beginners and veterans, most points are typically lost to wind. Successful shooters put a lot of thought into their approach to wind shooting. Sometimes it’s best to shoot fast and minimize the changes you’ll have to navigate. Other times it’s best to wait out a condition which may take several minutes. Develop a comfortable rest position so you have an easier time waiting when you should be waiting.

Competition TIP THREE. Actively avoid major train wrecks. Sounds obvious but it happens a lot. Select equipment that is reliable, get comfortable with it and have back-ups for important things. Don’t load on the verge of max pressure, don’t go to an important match with a barrel that’s near shot out, physically check tightness of all important screws prior to shooting each string. Observe what train wrecks you and others experience, and put measures in place to avoid them.

Bryan Litz Tips

Photos by Steve Fiorenzo

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January 13th, 2014

Digital Edition of Litz Accuracy and Precision Book Is Now Available

digital edition accuracy and precision for long range shooting bryan litzMore and more people are reading books on tablet computers and eReader devices such as the Kindle and Nook. Recognizing the demand for digital resource works, Applied Ballistics has just releases of its first eBook — a digital version of Accuracy and Precision for Long Range Shooting. This work (which has sold 5000 hard copy versions), is now available in electronic format for both Kindle and Nook eReaders. iPad users can use the Kindle app to access the eBook.

This book discusses how to evaluate multiple variables to improve your hit percentage. It explains how to correct the trajectories for drop, wind deflection, etc. through the use of Weapon Employment Zone (WEZ) analysis. WEZ is applied throughout the book, showing readers how to get more rounds on targets, more reliably. Case studies (with live fire verification for many scenarios) show what things affect your hit probability at long range.

All formats of the eBook are sold for $27.99 (hardcopy is $34.99). The Kindle book is available directly from Amazon.com, while the Nook version can be purchased from BarnesandNoble.com.

Free eReader Content on Applied Ballistics Website
If you have a Kindle, Nook, or iPad, you should visit the Ballistics website. You’ll find many free technical articles you can download as PDF files or in Kindle format or Nook format. To access these FREE articles, select the “Recreational” or “Professional” tabs on the top of the Applied Ballistics home page, then choose the “Articles” link from the pull-down menu. Bryan Litz tells us: “We recently updated our website and we’ve included a number of free articles about bullet design, long-range ballistics, and aspects of WEZ analysis. You don’t need an eReader for these — just download the PDF versions.”

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December 20th, 2013

How Altitude and Air Pressure Influence Ballistics

Suunto AltimeterOne of our readers asked “What effect does altitude have on the flight of a bullet?” The simplistic answer is that, at higher altitudes, the air is thinner (lower density), so there is less drag on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth’s surface (for practical purposes), the bullet’s downward acceleration doesn’t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.

Forum member Milanuk explains that the key factor is not altitude, but rather air pressure. Milanuk writes:

“In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000′ ASL or less. I’ll need about 29-30 MOA to get from 100 yard to 1000 yards with a Berger 155gr VLD @ 2960fps. By contrast, in Raton, NM, located at 6600′ ASL, I’ll only need about 24-25 MOA to do the same. That’s a significant difference.

Note that it is the barometric pressure that really matters, not simply the nominal altitude. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.”

As Milanuk states, it is NOT altitude per se, but the LOCAL barometric pressure (sometimes called “station pressure”) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect.

It’s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet amsl), if the local pressure is 24″, the radio will report the barometric pressure to be 30″. If you do high altitude shooting at long range, bring along a Kestral, or remember to mentally correct the radio station’s pressure, by 1″ per 1,000 feet.”

You can do your own experimental calculations using JBM Online Ballistics (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0′ altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.

Trajectory of Bullet fired at Sea Level

Trajectory of Bullet fired at 20,000 feet

if you want to learn more about all aspects of External Ballistics, ExteriorBallistics.com provides a variety of useful resources. In particular, on that site, Section 3.1 of the Sierra Manual is reprinted, covering Effects of Altitude and Atmospheric Pressure on bullet flight.

Permalink Tech Tip 5 Comments »
December 12th, 2013

New .338 Lapua Magnum XS4 Rifle from TrackingPoint

TrackingPoint, creator of the Precision Guided Firearm (PGF) system, has released a new “smart rifle”, the XS4 .338 Lapua Magnum. The XS4 boasts TrackingPoint’s revolutionary TTX (Tag Track Xact) technology — a system that automates aiming and ballistic correction once you have “tagged” the target with a laser beam. Along with the exotic computerized targeting system, the new XS4 features top-flight conventional components: Surgeon XL action, 27″ Krieger barrel, and McMillan A5 hunting stock. Full rifle weight including laser/digital/optical scope, two batteries, loaded magazine, muzzle brake, and bipod, is 22.5 pounds.

tracking point PGF laser tagging rifle

Like TrackingPoint’s XS1, the new XS4 has a maximum TTX range of 1,200 yards, the longest effective range offered by the company. The rifle’s 27-inch, Krieger cut-barrel is fitted in a traditional-style, adjustable McMillan A5 stock. It also features TrackingPoint’s highest-power zoom optic, offering 6x to 35X magnification. “Our customers have been asking for the power of our 338 Lapua Magnum smart rifles in the form factor of our popular XS3 hunting model,” said John Lupher, Chief Technology Officer for TrackingPoint. Pre-orders for the XS4 are now being accepted. The rifle will be demonstrated at the 2014 NSSF SHOT Show and other trade shows in 2014. To learn more about the XS4 Precision Guided Firearm, visit Tracking-Point.com.

Permalink Hunting/Varminting, New Product No Comments »
November 30th, 2013

Shooting Skills: Reading the Wind When Hunting

Norway Hunting Snow

Thomas Haugland, a Shooters’ Forum member from Norway, is a long-range target shooter and hunter. He has created an interesting video showing how to gauge wind velocities by watching trees, grass, and other natural vegetation. The video commentary is in English, but the units of wind speed (and distance) are metric. Haugland explains: “This is not a full tutorial, but rather a short heads-up to make you draw the lines between the dots yourself”. Here are some conversions that will help when watching the video:

.5 m/s = 1.1 mph | 1 m/s = 2.2 mph | 2 m/s = 4.5 mph
3 m/s = 6.7 mph | 4 m/s = 8.9 mph | 5 m/s =11.2 mph

More Interesting Videos from Norway
There are many other interesting videos on Haugland’s YouTube Channel, including Game Stalking, Precision Reloading, and Tips on how to use a Mildot Reticle on a scope with MOA-based clicks.

Permalink - Videos, Hunting/Varminting, Shooting Skills 3 Comments »
November 18th, 2013

NEW Book: The Practical Guide to Long Range Hunting Cartridges

Nathan Foster Practical Guide Long Range Hunting CartridgesIf you really want to learn about long-range hunting, listen to a pro, a man like Nathan Foster who has spent a life-time in the field. Nathan has just released a new book: The Practical Guide to Long Range Hunting Cartridges. You can trust what Nathan says. He has spent decades in the wild, harvesting over 7500 head of game. Nathan’s richly-illustrated, 415-page resource guides you through the process of choosing the best cartridge and projectile(s) for your hunts. The book begins by explaining the key principles of of long-range hunting. Then Nathan examines the pros and cons of various cartridges so that the reader can select the best cartridge and projectile to get the job done.

Nathan is truly a hunting expert. Nathan has spent thousands of hours in the field and he knows the subject cold. Unlike some outdoor writers, Nathan doesn’t pull punches — he tells the unvarnished truth about what works and what doesn’t. Here’s what Nathan says about his new book:

After many months of writing, it is now done, 415 pages of research, each bullet repeat-tested in the field, my research scrutinized by veterinarian surgeons [and] industry peers. It was truly an immense undertaking.

Nathan Foster Practical Guide Long Range Hunting CartridgesFor several years, I have received two types of email. The first question is which is the right rifle for me? The second question is which is the right cartridge? My first book dealt with the accurate rifle. This second book deals with long range hunting cartridge selection. I firmly believe that there has been a huge gap in education regarding optimal long range hunting cartridge performance. In many instances, both hunters and bullet manufacturers do not understand what’s required to achieve goals. Many times, the wrong tools are used for long range hunting. This book seeks to remedy these problems.

In the Practical Guide to Long Range Hunting Cartridges, I start with the fundamentals of game killing — but from the perspective of the long range hunter (also encountering close range shots). This section is not politically correct in any way, as after the study of anatomy, I explore worst case scenarios in as much depth as ideal shot placement.

The second section of the book is a study of projectile design. I wanted to get right down to the finer details of the long range hunting bullet in this section, exploring manufacturers, manufacturing techniques, and ways in which the end user can perform preliminary testing as well as bullet modifications.

The third section explains how to select a long range hunting cartridge. The system I have used here is based on a selection method I developed over the years to help clients worldwide. This method takes individual circumstances into consideration rather than a one size fits all approach. It is a system that relies on plain common sense based on research.

The fourth section of the book is the cartridge section. Cartridge information is presented in a set format with Pro/Con summary tables. In many instances I have included my own load notes. I have also included notes regarding how to approach close range shots with each of our long range cartridges.

Book Buyer Comment: “Nathan has ‘hit it out of the park’ with his 2nd book, The Practical Guide to Long Range Hunting Cartridges! This is definitely the ‘go-to’ manual for decision-making for hunters around the world. Where else can you fine such a wealth of information on bullet selection for a particular cartridge based on the weight of the animal you intend to pursue. This allows the hunter to make an educated decision on the best cartridge for a particular game species or to load that round, up or down, to cover a variety of game species in their location.” — Jim Moseley, North Carolina, USA


Nathan Foster Practical Guide Long Range Hunting CartridgesAbout the Author: New Zealander Nathan Foster lives and breathes what he teaches. An expert in the field of terminal ballistics, Nathan has taken over 7500 head of game, and has field-tested a vast number of cartridges and projectiles. Nathan’s first book, The Practical Guide to Long Range Hunting Rifles, is widely recognized as one of the best books ever published on the subject. The new book goes into greater detail on specific cartridges. Nathan’s website includes an outstanding online cartridge knowledge base with over 60 detailed cartridge profiles. CLICK HERE for Cartridge INFO.

Nathan runs Terminal Ballistics Research, a small company in Taranaki, New Zealand, that conducts cartridge and projectile performance research. Nathan also operates a long-range shooting school. Nathan is also the creator of MatchGrade Bedding Products.

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October 25th, 2013

Good Resource: The Wind Book for Rifle Shooters

The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails.” — William Arthur Ward

Readers often ask us: “Is there a decent, easy-to-comprehend book that can help my wind-reading?” Many of our Forum members have recommended The Wind Book for Rifle Shooters by Linda Miller and Keith Cunningham. This 146-page book, published in 2007, is a very informative resource. But you don’t have to take our word for it. If you click this link, you can read book excerpts and decide for yourself. When the Amazon page opens, simply click the book cover (labeled “Look Inside”) and another screen will appear. This lets you preview the first few chapters, and see some illustrations.

Other books cover wind reading in a broader discussion of ballistics or long-range shooting, such as Applied Ballistics for Long-Range Shooting by Bryan Litz. But the Miller & Cunningham book is ALL about wind reading from cover to cover, and that is its strength. The book focuses on real world skills that can help you accurately gauge wind angle, wind velocity, and wind cycles.

All other factors being equal, it is your ability to read the wind that will make the most difference in your shooting accuracy. The better you understand the behavior of the wind, the better you will understand the behavior of your bullet. — Wind Book for Rifle Shooters

The Wind Book for Rifle Shooters contains straightforward guidance on the thought processes, techniques, and tactics used by expert wind-readers. The written text is supplemented by numerous easy-to-understand charts and illustrations. The authors show you how to put together a simple wind-reading “toolbox” for calculating wind speed, direction, deflection and drift. Then they explain how to use these tools to read flags and mirage, record and interpret your observations, and time your shots to compensate for wind. The essential wind-reading basics taught in this book can definitely help any shooter. Here are some reviews from actual book buyers:

I believe this is a must-have book if you are a long-range sport shooter. I compete in F-Class Open and when I first purchased this book and read it from cover to cover, it helped me understand wind reading and making accurate scope corrections. Buy this book, read it, put into practice what it tells you, you will not be disappointed. — P. Janzso

If you have one book for wind reading, this should be it. Whether you’re a novice or experienced wind shooter this book has something for you. It covers how to get wind speed and direction from flags, mirage, and natural phenomenon. The book also details methods for recording shots and improving your shooting and thus your wind reading skills. In my opinion this is the best book for learning to read wind speed and direction. — Muddler

I found this book to be something I have needed for quite a while. I have been shooting Long Range for 20 years and always had problems with the wind. I would just chase the spotter. This book makes it all make sense. — L. Cash

As far as I know this is the only book of its type. It’s very well written in a way that’s easy to understand for such a complex subject. The charts and graphs are extremely helpful. It’s a bit on the short side at about 146 pages but still packed with knowledge. — R. Johnson

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October 24th, 2013

Software Update for Applied Ballistics Kestrel Weather Meter

Kestrel Weather meter wind gauge software update Bryan Litz applied ballisticsThe Applied Ballistics Kestrel 4500 Shooters’ Weather Meter has a new software upgrade available. You will find instructions for connecting and upgrading your Kestrel 4500 at this link:

CLICK HERE for Applied Ballistics
Kestrel Software Upgrade
.

Read Comments on Sniper’s Hide Forum
Also, there is a thread on the Snipers Hide Forum in which Applied Ballistics and Kestrel Pro Staff are responding to questions/issues related to use of the Applied Ballistics Kestrels.

Bryan Litz of Applied Ballistics LLC wants to express appreciation for Kestrel users who have posted input: “Thanks to the users who provided valuable feedback that was used to make the product better.”

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October 16th, 2013

Litz Battles Rain and Cold To Film ‘Putting Rounds on Target’

bryan litz dvd putting rounds on target

bryan litz dvd putting rounds on targetAs you may know already, Bryan Litz of Applied Ballistics LLC has produced an excellent 3-Disc DVD set entitled Putting Rounds on Target. When one views the end result one can forget the hard work and tribulations that go into making such a production. Sometimes Mother Nature doesn’t cooperate when the crew is out at the range.

Bryan tells us:

“Filming for ‘Putting Rounds on Target’ proved to be a bit more challenging then we had expected. For this segment in the third disk, we packed up and set up everything over half a dozen times to keep the camera and shooting equipment dry as the sun played Peek-a-boo behind rain clouds. The chilled temperatures, required a lot of hot coffee, but the lack of restrooms made for a long day. In the end, it was totally worth it!

Watch Trailer Video of Putting Rounds on Target DVD Set

bryan litz dvd putting rounds on target

bryan litz dvd putting rounds on target

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October 13th, 2013

Brain Teaser: Do You Know the Rule of the Square?

wind drift wind reading 6mmbr rule of the squareHorizontal Wind-Drift vs. Distance
OK, here’s a challenge question for you.
Let’s see if you get it right.

Q: If the wind is blowing 10 mph from 9 o’clock and if my horizontal wind deflection is 0.7 inches at 100 yards, what is the horizontal drift at 1000 yards?

You may be thinking, “Well, since the target is ten times more distant, the wind-drift should be around 7 inches, maybe a little more since the bullet will be slowing down.” That sounds reasonable, right?

WRONG.

As you move from near to far, the increase in lateral deflection (from a 90° crosswind) is (roughly speaking) a function of the square of the multiple of distance. If your target is two times farther away, you use the square of two, namely four. If your target is five times farther away, you use the square of five, or twenty-five. In this example, the increased wind drift (from 100 to 1000 yards) is at least 0.7″ times (10 X 10) — over 70 inches (give or take a few inches depending on bullet type). We call that the Rule of the Square. This Rule lets you make a quick approximation of the windage correction needed at any yardage.

Precision Shooting and the Rule of the Square
I was going through some back issues of Precision Shooting Magazine and found many references to the Rule of the Square. This made me curious — I wondered how well the Rule really stacked up against modern ballistics programs. Accordingly, I ran some examples through the JBM Ballistics Trajectory Calculator, one of the best web-based ballistics programs. To my surprise, the Rule of the Square does a pretty good job of describing things.

EXAMPLE ONE — .308 Win (100 to 400 Yards)
For a 168gr Sierra MK (.308), leaving the muzzle at 2700 fps, the JBM-predicted values* are as follows, with a 10 mph, 9 o’clock crosswind (at sea level, 65° F, Litz G7 BC):

Drift at 100: 0.8 MOA (0.8″)
Drift at 200: 1.6 MOA (3.3″)
Drift at 400: 3.4 MOA (14.4″)

Here you can see how the Rule of the Square works. The rule says our drift at 200 yards should be about FOUR times the drift at 100. It the example above, 0.8″ times 4 is 3.2″, pretty darn close to the JBM prediction of 3.3″. Quoting Precision Shooting: “Note that the deflections at 100 yards are typically a quarter of those at 200; lateral deflections increase as the square of the range”. Precision Shooting, June 2000, p. 16.

EXAMPLE TWO — .284 Win (100 to 1000 Yards)
For a .284 Win load, with the slippery Berger 180gr Target Hybrids, the Rule of the Square still works. Here we’ll input a 2750 fps velocity, Litz G7 BC, 10 mph, 9 o’clock crosswind, (same 65° temp at sea level). With these variables, JBM predicts:

Drift at 100: 0.5 MOA (0.5″)
Drift at 500: 2.5 MOA (13.3″)
Drift at 1000: 5.9 MOA (61.3″)

Again, even with a higher BC bullet, at 1000 yards we end up with something reasonably close to the 100-yard deflection (i.e. 0.5″) multiplied by (10×10), i.e. 50 inches. The Rule of the Square alerts you to the fact that the effects of crosswinds are MUCH greater at very long range. In this example, our JBM-calculated drift at 1000 is 61.3″ — that’s over 100 times the 100-yard lateral drift, even though the distance has only increased 10 times.

Note that, even with a 5 mph 90° sidewind, the “Rule of the Square” still applies. The 1000-yard lateral deflection in inches is still over 100 times the lateral deflection at 100 yards.


Why This All Matters (Even in the Age of Smartphones)
wind drift wind reading 6mmbr rule of the squareNow, some would say, “Why Should I Care About the Rule of the Square? My iPhone has a Ballistics App that does all my thinking for me”. Fair enough, but knowledge of this basic Rule of the Square enables a shooter to make an informed guess about necessary windage even without a come-up sheet, as long as he knows the distance AND can fire a sighter at 100 or 200 yards as a baseline.

For example, if I see empirically that I need 1″ windage correction at 100 yards, then I know that at 600 yards I need at least roughly (6 x 6 x 1″) or 36 total inches of drift correction, or 6 MOA. (To be precise, 1 MOA = 1.047″ at 100 yards). I can figure that out instantly, even without a ballistics chart, and even if my Smartphone’s battery is dead.

*Values shown are as displayed on the JBM-figured trajectory tables. The numbers can be slightly imprecise because JBM rounds off to one decimal place for both inches and MOA.

Permalink Shooting Skills, Tech Tip 1 Comment »
September 21st, 2013

Lapua Releases Doppler Radar Data for Lapua Scenar-L Bullets

Lapua has done extensive field testing of its bullets, using sophisticated Doppler radar equipment. Employing radar, Lapua has logged actual observed trajectories with a variety of bullet and cartridge types. And Lapua has just released updated radar data for Scenar-L bullets used with 6.5×47 Lapua, 6.5×55 Swede, and .308 Winchester chamberings. You’ll find this new data incorporated into Lapua’s product description tables for these three cartridge types.

Lapua doppler radar dataYou will also find both G1 and G7 BCs for the new line of Scenar-L Bullets in Lapua’s updated Components Table. Ballistic coefficients are based on Doppler radar data and calculated by Quick Target Unlimited Lapua Edition.

To find the BC for a particular bullet, go to the Components Table, select the caliber (on the left) and then look for the G1 or G7 value on the right for particular bullets. For example, the BCs for the new 136gr 6.5mm Scenar-L are 0.545 (G1) and 0.274 (G7).

If you are looking for the most precise trajectory predictions, nothing beats real-world testing like this. Bullet BCs can be calculated, “on paper”, from bullet size, weight, and shape. However, in the ‘real world’ the actual aerodynamic drag forces acting on the bullet change with velocity and other variables. Therefore, a bullet’s BC is NOT actually constant at every point in its flight path. Doppler radar allows Lapua to observe the actual drop of bullets at multiple points along their trajectory.

How much more precise are Doppler-radar-based trajectory predictions than typical drop charts based on modeled BCs? Consider this… when you plug the radar-based numbers for a .338 Lapua Magnum into Lapua’s ballistics software, the error in elevation is less than 2.5 cm (1″) at 1,500 meters. By contrast, the error based on a traditional G1 BC model could be over 1 meter (i.e. more than 40 inches).

Lapua doppler radar data

Free Lapua Ballistics Software for Android OS Devices
If you want to use Lapua’s Doppler Radar data for your own ballistics calculations — there’s a App for that. Lapua’s Quick Target Unlimited (QTU) software for Android OS can be downloaded for free from the Android Market. Predicted trajectories for this software are based on precise Doppler radar ballistic measurements of Lapua bullets, making this program much more accurate than other ballistic programs for mobile phones. Note, however, the Doppler Radar data is offered ONLY for Lapua-made bullets. This App does NOT include radar data for Berger, Sierra or other brands of bullets.

Lapua doppler radar data

Product tip from EdLongrange. We welcome reader submissions.
Permalink Bullets, Brass, Ammo, News 3 Comments »