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May 20th, 2022

How Muzzle Velocity Changes with Different Barrel Twist Rates

applied Ballistics Barrel Twist rate velocity testing test bryan Litz
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.

Does muzzle velocity change with faster or slower barrel twist rates? Absolutely, but much less than you might think. Faster twist rates do slow down bullets somewhat, but the speed loss is NOT that significant. With Bartlein .308 Win barrels of identical length and contour, a 1:12″-twist barrel was only 8 fps faster than a 1:8″-twist barrel. That was the result of testing by Applied Ballistics.

The Applied Ballistics team tested six (6) same-length/same-contour Bartlein barrels to observe how twist rate might affect muzzle velocity. This unique, multi-barrel test is featured in the book Modern Advancements in Long Range Shooting, Vol. 1. That book includes other fascinating field tests, including a comprehensive chronograph comparison.

applied Ballistics Barrel Twist rate velocity testing test bryan Litz

applied Ballistics Barrel Twist rate velocity testing test bryan Litz
Barrel Twist Rate vs. Velocity — What Tests Reveal
by Bryan Litz
When considering barrel twist rates, it’s a common belief that faster twist rates will reduce muzzle velocity. The thinking is that the faster twist rate will resist forward motion of the bullet and slow it down. There are anecdotal accounts of this, such as when someone replaces a barrel of one brand/twist with a different brand and twist and observes a different muzzle velocity. But how do you know the twist rate is what affected muzzle velocity and not the barrel finish, or bore/groove dimensions? Did you use the same chronograph to measure velocity from both barrels? Do you really trust your chronograph?

Summary of Test Results
After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 FPS per inch of twist. In other words, your velocity is reduced by about 5 FPS if you go from a 1:12″ twist to a 1:8″ twist. — Bryan Litz

Savage Test Rifle with Six Bartlein Barrels
Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied Ballistics

Most shooters don’t have access to the equipment required to fully explore questions like this. These are exactly the kinds of things we examine in the book Modern Advancements in Long Range Shooting, Vol. 1. In that book, we present experiments conducted in the Applied Ballistics lab. Some of those experiments took on a “Myth Buster” tone as we sought to confirm (or deny) popular pre-conceptions. For example, here’s how we approached the question of barrel twist and muzzle velocity.

Six .308 Win Barrels from Bartlein — All Shot from the Same Rifle
We acquired six (6) barrels from the same manufacturer (Bartlein), all the same length and contour, and all chambered with the same reamer (SAAMI spec .308 Winchester). All these barrels were fitted to the same Savage Precision Target action, and fired from the same stock, and bench set-up. Common ammo was fired from all six barrels having different twist rates and rifling configurations. In this way, we’re truly able to compare what effect the actual twist rate has on muzzle velocity with a reasonable degree of confidence.

Prior to live fire testing, we explored the theoretical basis of the project, doing the physics. In this case, an energy balance is presented which predicts how much velocity you should expect to lose for a bullet that’s got a little more rotational energy from the faster twist. In the case of the .30 caliber 175 grain bullets, the math predicts a loss of 1.25 fps per inch-unit of barrel twist (e.g. a 1:8″ twist is predicted to be 1.25 fps slower than a 1:9″ twist).

Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied Ballistics

Above, data shows relationship between Twist Rate and Muzzle Velocity (MV) for various barrel twist rates and rifling types. From fast to slow, the three 1:10″ twist barrels are: 5R (canted land), 5 Groove, 5 Groove left-hand twist.

We proceeded with testing all 6 barrels, with twist rates from 1:8″ to 1:12″. After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 fps per inch of twist. In other words, your velocity is reduced by about 5 fps if you go from a 1:12″ twist to a 1:8″ twist. [Editor: That’s an average for all the lengths tested. The actual variance between 1:12″ and 1:8″ here was 8 FPS.] In this case the math prediction was pretty close, and we have to remember that there’s always uncertainty in the live fire results. Uncertainty is always considered in terms of what conclusions the results can actually support with confidence.

Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied BallisticsThis is just a brief synopsis of a single test case. The coverage of twist rates in Modern Advancements in Long-Range Shooting Vol. 1 is more detailed, with multiple live fire tests. Results are extrapolated for other calibers and bullet weights. Needless to say, the question of “how twist rate affects muzzle velocity” is fully answered.

Other chapters in the book’s twist rate section include:
· Stability and Drag — Supersonic
· Stability and Drag — Transonic
· Spin Rate Decay
· Effect of Twist rate on Precision

Other sections of the book include: Modern Rifles, Scopes, and Bullets as well as Advancements in Predictive Modeling. This book is sold through the Applied Ballistics online store. Modern Advancements in Long Range Shooting is also available as an eBook in Amazon Kindle format.

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May 2nd, 2022

Do Chron Your Factory Ammo — Stated Velocities May Be Wrong

muzzle velocity applied Ballistics MV chronograph

Why You CANNOT Rely on the MV Printed on the Ammo Box!
When figuring out your come-ups with a ballistics solver or drop chart it’s “mission critical” to have an accurate muzzle velocity (MV). When shooting factory ammo, it’s tempting to use the manufacturer-provided MV which may be printed on the package. That’s not such a great idea says Bryan Litz of Applied Ballistics. Don’t rely on the MV on the box, Bryan advises — you should take out your chrono and run your own velocity tests. There are a number of reasons why the MV values on ammo packaging may be inaccurate. Below is a discussion of factory ammo MV from the Applied Ballistics Facebook Page.

Five Reasons You Cannot Trust the Velocity on a Box of Ammo:

1. You have no idea about the rifle used for the MV test.

2. You have no idea what atmospheric conditions were during testing, and yes it matters a lot.

3. You have no idea of the SD for the factory ammo, and how the manufacturer derived the MV from that SD. (Marketing plays a role here).

4. You have no idea of the precision and quality of chronograph(s) used for velocity testing.

5. You have no idea if the manufacturer used the raw velocity, or back-calculated the MV. The BC used to back track that data is also unknown.

1. The factory test rifle and your rifle are not the same. Aside from having a different chamber, and possibly barrel length some other things are important too like the barrel twist rate, and how much wear was in the barrel. Was it just recently cleaned, has it ever been cleaned? You simply don’t know anything about the rifle used in testing.

2. Temperature and Humidity conditions may be quite different (than during testing). Temperature has a physical effect on powder, which changes how it burns. Couple this with the fact that different powders can vary in temp-stability quite a bit. You just don’t know what the conditions at the time of testing were. Also a lot of factory ammunition is loaded with powder that is meter friendly. Meter friendly can often times be ball powder, which is less temperature stable than stick powder often times.

3. The ammo’s Standard Deviation (SD) is unknown. You will often notice that while MV is often listed on ammo packages, Standard Deviation (normally) is not. It is not uncommon for factory ammunition to have an SD of 18 or higher. Sometimes as high as 40+. As such is the nature of metering powder. With marketing in mind, did they pick the high, low, or average end of the SD? We really don’t know. You won’t either until you test it for yourself. For hand-loaded ammo, to be considered around 10 fps or less. Having a high SD is often the nature of metered powder and factory loads. The image below is from Modern Advancements in Long Range Shooting: Volume II.

muzzle velocity applied Ballistics MV chronograph

4. You don’t know how MV was measured. What chronograph system did the manufacturer use, and how did they back track to a muzzle velocity? A chronograph does not measure true velocity at the muzzle; it simply measures velocity at the location it is sitting. So you need to back-calculate the distance from the chrono to the end of the barrel. This calculation requires a semi-accurate BC. So whose BC was used to back track to the muzzle or did the manufacturer even do that? Did they simply print the numbers displayed by the chronograph? What kind of chronograph setup did they use? We know from our Lab Testing that not all chronographs are created equal. Without knowing what chronograph was used, you have no idea the quality of the measurement. See: Applied Ballistics Chronograph Chapter Excerpt.

5. The MV data may not be current. Does the manufacturer update that data for every lot? Or is it the same data from years ago? Some manufacturers rarely if ever re-test and update information. Some update it every lot (ABM Ammo is actually tested every single lot for 1% consistency). Without knowing this information, you could be using data for years ago.

CONCLUSION: Never use the printed MV off a box of ammo as anything more than a starting point, there are too many factors to account for. You must always either test for the MV with a chronograph, or use carefully obtained, live fire data. When you are using a Ballistic Solver such as the AB Apps or Devices integrated with AB, you need to know the MV to an accuracy down to 5 fps. The more reliable the MV number, the better your ballistics solutions.

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April 29th, 2022

Team Competition — How to Make and Use a Wind Plot

wind plot Bryan Litz FCWC Canada F-Class World Championship
CLICK HERE to see full-screen version of Wind Plot.

Team shooting is very different than individual competition. Typically a team coach makes the wind calls for the shooters. In some cases (where the rules allow), the wind coach even dials elevation and windage changes for the active shooter. For the wind coach to do his job effectively, he must follow the changes in the wind and determine what the correct wind call should have been for each shot. (In other words — what was the “right call”)

Bryan Litz, founder of Applied Ballistics and Past USA F-TR National Champion, served as wind coach for the winning 4-man F-TR Team at the 2017 Canadian F-Class Championships, which preceded the F-Class World Championships also held in Canada. Here Bryan explains how he has used a Wind Plot to make better wind calls, helping his team-mates maximize their scores.

wind calling plot log technique

Wind Plot Methodology by Bryan Litz

The wind plot I use is a running history of what the correct wind call was for every shot fired. The more you shoot, the more history you have in a condition, and I find that very useful information. This kind of plot IS NOT showing where the bullet hit, and is NOT showing what you held. It’s showing what you should have held to center each shot. IMO, this is the most valuable information to have when guessing where to hold next for each shot. Here are some key points:

1. I always look for blocks of stable conditions to shoot in and wait out the rest.

2. If the wind plot shows drastic changes, either I’m not picking the right time to shoot or it’s just a really unstable wind condition.

3. When you see many shots using the same hold (e.g. Robby’s 700m and 900m strings on plot), it can indicate very fast shooting and fast pit service.

Q. What are the numbers and Markings on this Wind Plot?
Litz: The wind plot represents the rings on the target. Left 2 for example, is the 5 line on the international target, while Left 2 is the 10 line on the USA target. F-Class shooters and coaches talk about wind holds in relation to these rings. A Left 2 hold isn’t left 2 MOA or 2 MILS, it’s the second ring from center. The vertical lines on the plot represent the rings going out from center, 4 or 5 in each direction. A left or right 5 hold is edge of black on the int’l target.

wind plot Bryan Litz FCWC Canada F-Class World Championship

Q: What Does this Specific Plot Reveal?
Litz: Looking at the plot, from left to right is 700m, 800m, and 900m that we shot progressively through the day. Top to bottom shows each shooter in sequence (shooters names are shown by their blocks). To the right I note what was on the gun for that shooter, and note when it changes. Often times we run the same wind on the gun for several shooters but if it changes, I note what the new windage is and continue on. For example if we’re settled into a condition where we’re shooting Vs with a right 3 hold, I might adjust the scope 1 MOA right because a right 3 hold is equal to 1 MOA. So we can move the scope and start shooting with a center hold.

Q. Are you Plotting Where the Bullet Hits?
Litz: Not exactly. This kind of plot IS NOT specifically showing where the bullet hit, and IS NOT showing what the shooter held. It’s showing what the shooter should have held to center each shot. IMO, this is the most valuable information to have when guessing where to hold next for each shot.

On each shot, the shooter or coach takes a guess about where to hold, and fires the shot. If the bullet hits the center, you plot the point right where you held because it was the correct hold. However, if you miss the call, you plot what hold was required to put that shot in the center. For example if you shoot a right 3 and hit where you held, the correct call would have been “center”. In this way, you’re building a history of what you should have done, which may or may not be what you actually did. This shows you the trends, and brackets which can be used to make future decisions.

Q: Is this Type of Wind Plot Something New?
Litz: I didn’t invent this method, it’s been around a long time. Vertical can be plotted the same way. In team matches, we have a plotter who is advising on elevation trends and suggesting corrections. But, as wind coach, my job is the horizontal so I only keep the wind plot. I have learned lots of strategies from my coaches Emil Praslick and Steve Hardin.

There are many ways to plot and many standard work sheets for this. They’re all tools and the key is to find something that works for you in different situations. I don’t keep a plot when I am personally behind the trigger string firing because I lose more points when I take the time to do it vs. just shooting fast. When pair firing or coaching, I can keep the wind plot without compromising the shooting.

2013 F-Class World Championships
Here Team Australia used plots and communication gear linking coaches. This helped the Aussies win the 2013 F-Open Team World Championship held at Raton, NM.

Know Your Goal — Keep It Simple
Know your goal of plotting. The simplest plot is where you write the shot number where it hit on a target face. This kind of plotting is useful for evaluating shooter performance because it shows how big the group is (in particular the vertical dispersion). However keeping a plot like this does little to help you figure out the wind. It just shows you what shots you messed up on. It does nothing to help you find the center. [Editor: That’s a whole different matter with many variables.] The wind plot I use is a running history of what the correct wind call was for every shot fired. The more you shoot, the more history you have in a condition, and I find that very useful information.

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April 27th, 2022

MIL vs. MOA — Angular Measurements for Optics Explained

Mil MOA reticle ranging PRS tactical minute angle precision rifle series
Visit PrecisionRifleBlog.com for a discussion of MIL vs. MOA.

Many guys getting started in long range shooting are confused about what kind of scope they should buy — specifically whether it should have MIL-based clicks or MOA-based clicks. Before you can make that decision, you need to understand the terminology. This article, with a video by Bryan Litz, explains MILS and MOA so you can choose the right type of scope for your intended application.

This March-FX 5-40x56mm Tactical FFP scope features 0.05 MIL Clicks.
Mil MOA reticle ranging PRS tactical minute angle precision rifle series

You probably know that MOA stands for “Minute of Angle” (or more precisely “minute of arc”), but could you define the terms “Milrad” or “MIL”? In a helpful video, Bryan Litz of Applied Ballitics explains MOA and MILs (short for “milliradians”). Bryan defines those terms and explains how they are used. One MOA is an angular measurement (1/60th of one degree) that subtends 1.047″ at 100 yards. One MIL (i.e. one milliradian) subtends 1/10th meter at 100 meters; that means that 0.1 Mil is one centimeter (1 cm) at 100 meters. Is one angular measurement system better than another? Not necessarily… Bryan explains that Mildot scopes may be handy for ranging, but scopes with MOA-based clicks work just fine for precision work at known distances. Also because one MOA is almost exactly one inch at 100 yards, the MOA system is convenient for expressing a rifle’s accuracy. By common parlance, a “half-MOA” rifle can shoot groups that are 1/2-inch (or smaller) at 100 yards.

What is a “Minute” of Angle?
When talking about angular degrees, a “minute” is simply 1/60th. So a “Minute of Angle” is simply 1/60th of one degree of a central angle, measured either up and down (for elevation) or side to side (for windage). At 100 yards, 1 MOA equals 1.047″ on the target. This is often rounded to one inch for simplicity. Say, for example, you click up 1 MOA (four clicks on a 1/4-MOA scope). That is roughly 1 inch at 100 yards, or roughly 4 inches at 400 yards, since the target area measured by an MOA subtension increases with the distance.

one MOA minute of angle diagram

MIL vs. MOA for Target Ranging
MIL or MOA — which angular measuring system is better for target ranging (and hold-offs)? In a recent article on his PrecisionRifleBlog.com website, Cal Zant tackles that question. Analyzing the pros and cons of each, Zant concludes that both systems work well, provided you have compatible click values on your scope. Zant does note that a 1/4 MOA division is “slightly more precise” than 1/10th mil, but that’s really not a big deal: “Technically, 1/4 MOA clicks provide a little finer adjustments than 1/10 MIL. This difference is very slight… it only equates to 0.1″ difference in adjustments at 100 yards or 1″ at 1,000 yards[.]” Zant adds that, in practical terms, both 1/4-MOA clicks and 1/10th-MIL clicks work well in the field: “Most shooters agree that 1/4 MOA or 1/10 MIL are both right around that sweet spot.”

READ MIL vs. MOA Cal Zant Article.

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April 20th, 2022

Science of Accuracy Academy — New from Applied Ballistics

Bryan Litz long range Science of Accuracy Applied Ballistics

Applied Ballistics has just launched a great, new online resource for shooters: The Science of Accuracy Academy. This subscription-based website is launching with nearly 30 podcast episodes, with many more planned, as well as video content, Zoom classes, and much more.

The main goal of this new online resource is to adapt and modernize the delivery of content coming from Applied Ballistics LLC. In past years, books, DVDs, and seminars were the primary avenues for delivering information. Modern technology has evolved, and the delivery of information can be done in more efficient ways such as streaming videos, podcast discussions of book and seminar content. In addition to being a more modern delivery platform, The Science of Accuracy Academy allows for more frequent updates than traditional books and DVDs.

Bryan Litz, owner of Applied Ballistics LLC tells us: “I’m very excited about this avenue to share what we’re learning in the Applied Ballistics lab. I think many shooters will benefit from the podcasts, which contain very insightful discussions and can be enjoyed in your car, or as you work. We look forward to publishing more of our research thru the Science of Accuracy Academy”.

Bryan Litz long range Science of Accuracy Applied Ballistics

You can visit The Science of Accuracy Academy website at: thescienceofaccuracy.com. For full access to all Academy content and “members only” online events, a subscription runs $9.95/month.

Bryan Litz long range Science of Accuracy Applied Ballistics

About the Science of Accuracy Academy Content and Programs

Below, Bryan Litz comments about the Academy’s new podcast offerings and other interactive content. Bryan notes: “We’ve benefited a great deal from practicing the scientific method, and we want to share what we’ve learned.”

Book Content via Podcasts — Many of the podcast episodes are specific reviews of Applied Ballistics book chapters. I’ll sit with Mitch or Francis (both experienced, champion shooters) and discuss the chapter, what it was like to do the tests. We will also discuss behind the scenes problems, as well as what we’ve learned since publishing the books. This lets subscribers get knowledge from the books. And, as a podcast, you can listen while driving, working out, or whatever.

The World of Doppler Radar — In recent years we have spent considerable time visiting shooting matches with the AB Mobile Lab and running Doppler radar. Between that and some of the government contracting work, we’ve built up a lot of experiences and it’s been a long time since a book was published. This Academy is a great outlet for us to update the shooting world on what we’ve been doing and learning.

Ballistics Science and Precision Loading — We’ve been doing hardcore ballistic science for the past few years and have a lot to share. We’ve come to see some aspects of handloading and shooting in a fundamentally different way. For example, understanding the statistical nature of precision has caused us to re-shape how we make decisions in the handloading process. As a result, we now better understand cause-effect relationships and can make deliberate, reliable progress as a result.

Bryan Litz Announces the New Science of Accuracy Academy

The Lighter Side — Bryan told AccurateShooter.com: “Some of the podcast episodes are much less serious! We have fun arguing about which shooting disciplines are harder. For example, Mitch Fitzpatrick and I talk with Francis Colon and Chad Heckler about PRS vs. ELR shooting. We discuss what we like and dislike about the different sports, what we would like to see changed, and what competition shooting has meant for us as individuals. This open-ended format explores long range shooting from the technical to the personal and everything in-between.”

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April 19th, 2022

Wind Speed or Wind Direction — What Counts Most?

Wind reading bryan litz speed direction

Wind-Reading Lesson from Bryan Litz

Q: What’s more important — wind speed, or direction?

A: Obviously they both matter, but they do trade dominance based on direction. For example, a 10 mph wind between 2:30 and 3:30 is only changing its value from 9.7 to 10 to 9.7 mph (bracket of 0.3 mph). However a 10 mph wind between 11:30 and 12:30 is changing its cross wind component value from 2.6 mph left to zero to 2.6 mph right (bracket of 5.2 mph). There is the same 30° change in direction, but this results in a massively different bracket.

Point being, in this case, a direction change is far more critical if it’s near 6 or 12 o’clock. A small direction change when it’s close to 3 or 9 o’clock is negligible.

On the contrary, a change in wind SPEED when it’s near 3 or 9 affects your crosswind component directly. But for a near head or tail wind, a fluctuation in wind speed only causes a small fraction of a change to the crosswind component.

SUMMARY: If you’re in a near full-value wind, pay more attention to wind SPEED. If you’re closer to a head- or tail-wind, nailing the exact DIRECTION will be more important.

Get More Tips on Bryan Litz Ballistics Facebook Page
This post is from the new Bryan Litz Ballistics Facebook Page. FB users should check that page regularly for more tips from Bryan, American’s leading ballistics expert and founder of Applied Ballistics LLC.

READ MORE TIPS HERE: www.Facebook.com/BryanLitzBallitics

Bryan Litz coaching Team USA in Canada using a WIND PLOT.

BIG NEWS Coming Soon: Bryan Litz and Applied Ballistics will make a Major Announcement tonight, April 19, 2022. The Announcement will be featured on Facebook and other Social Media, and we’ll have a report in tomorrow’s Daily Bulletin.

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April 19th, 2022

Bullet Stability and Barrel Twist Rates — What You Need to Know

gunwerks bullet stability barrel twist rate video animation

Are you curious about bullet stabilization? Do you understand why bullets can tumble or become unstable if the velocity gets too low or if the twist rate is inadequate. Here is an excellent video from Gunwerks that explains Bullet Stabilization.

This animated video starts by showing the design/shape differences between an older-style rifle bullet and a newer VLD-style bullet with higher BCs (Ballistic Coefficients). Generally speaking, the longer a bullet gets relative to diameter, the more RPM is required for stability. And to achieve that higher RPM you need more barrel twist and/or more RPM. The video illustrates where the Center of Gravity and the Center of Pressure are located. These are farther apart (in relative terms) for a VLD or Hybrid-style, long-nose bullet.

gunwerks bullet stability barrel twist rate video animation

When the bullet is in flight there is an angle of attack. This is exaggerated in the animation for illustration purposes, but it is important to understand the the attack angle affect stability. The rotation rate (Revolutions Per Minute) is a function of bullet velocity as it leaves the muzzle and the twist rate of the barrel. Since long VLD-style bullets need more stability, the barrel twist rate needs to be higher than with shorter, fatter bullets. This is pretty much try for all calibers.

The importance of adequate barrel twist rates for bullet stabilization is further discussed in this next video featuring Bryan Litz of Applied Ballistics:

Bullet Stability and Twist Rates

In this video, Bryan Litz talks about bullet in-flight stability and how to calculate barrel twist-rate requirements for long-range bullets. Bryan explains that bullet stability (for conventional projectiles) is basically provided by the spinning of the bullet. But this spin rate is a function of BOTH the nominal twist rate of the barrel AND the velocity of the projectile. Thus, when shooting the same bullet, a very high-speed cartridge may work with a slower barrel twist rate than is required for a lower-speed (less powerful) cartridge. For match bullets, shot at ranges to 1000 yards and beyond, Bryan recommends a twist rate that offers good stability.

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April 2nd, 2022

Saturday at the Movies: Litz on Long Range Shooting + Ballistics

Bryan Litz Elements Long Range Shooting NSSF Ballistics Coeffecient Atmospherics

Want to learn more about Long Range Shooting? Check out the NSFF “Elements of Long Range Shooting” videos hosted by ballistics guru Bryan Litz of Applied Ballistics. In this multi-part series, Bryan covers a variety of topics of interest to precision shooters. For today’s Saturday at the Movies special, we feature seven of Bryan’s videos. Watch other informative Long Range Shooting and Ballistics videos with Bryan Litz on the NSSF YouTube Channel.

Litz NSSF Video Elements long range shooting Raton NM ELR

Atmospherics and Density Altitude

Bryan Litz explains: “An important element in calculating an accurate firing solution for long-range shooting is understanding the effects of atmospherics on a projectile.” Atmospherics include air pressure, air temperature, and humidity. Bryan notes: “Temperature, pressure, and humidity all affect the air density… that the bullet is flying through. You can combine all those factors into one variable called ‘Density Altitude’.” Density Altitude is used by the ballistic solver to account for variables that affect bullet flight.

Bullet Ballistic Coefficients

A bullet’s ballistic coefficient (BC) basically expresses how well the bullet flies through the air. Higher BC bullets have less aerodynamic drag than lower BC projectiles. You will see BCs listed as either G1 and G7 numbers. These correspond to different bullet shape models. Generally speaking, the G7 model works better for the long, boat-tail bullets used for long-range shooting. Notably, a bullet’s drag is NOT constant in flight. The true BC can vary over the course of the trajectory as the bullet velocity degrades. In other words, “BC is dynamic”. That said, you can make very accurate drop charts using the BCs provided by major bullet-makers, as plugged into solvers. However, long-range competitors may want to record “real world” drop numbers at various distances. For example, we’ve seen trajectories be higher than predicted at 500 yards, yet lower than predicted at 1000.

Transonic Range

When considering your rifle’s long-range performance, you need to understand the limit of your bullet’s supersonic range. As the bullet slows below the speed of sound, it enters the transonic zone. This can be accompanied by variations in stability as well as BC changes. Bryan explains “once your bullet slows done below supersonic and you get into transonic effects, there are a lot more considerations that come into play. The drag of the bullet becomes less certain, the stability of the bullet can be challenged, and things related to long times of flight, such as Coriolis and Spin Drift, come into play. So whenever you are shooting long range you need to where your bullet slows down to about 1340 fps.”

Ballistics Solvers — Many Options

Bryan Litz observes: “When we talk about the elements of long range shooting, obviously a very important element is a getting a fire solution, using a ballistic solver. There are a lot of ballistic solvers out there… Applied Ballistics has smartphone Apps. Applied Ballistics has integrated the ballistic solver directly into a Kestral, and the same solver runs (manually) on the Accuracy Solutions Wiz-Wheel. The point is, if it is an Applied Ballistics device it is running the same solutions across the board.”

Bullet Stability and Twist Rates

In this video, Bryan Litz talks about bullet in-flight stability and how to calculate barrel twist-rate requirements for long-range bullets. Bryan explains that bullet stability (for conventional projectiles) is basically provided by the spinning of the bullet. But this spin rate is a function of BOTH the nominal twist rate of the barrel AND the velocity of the projectile. Thus, when shooting the same bullet, a very high-speed cartridge may work with a slower barrel twist rate than is required for a lower-speed (less powerful) cartridge. For match bullets, shot at ranges to 1000 yards and beyond, Bryan recommends a twist rate that offers good stability.

Scope Tracking — Tall Target Test

Scope Click Verify Elevation Tall Target Bryan Litz NSSF test turret MOA MIL

Have you recently purchased a new scope? Then you should verify the actual click value of the turrets before you use the optic in competition. While a scope may have listed click values of 1/4-MOA, 1/8-MOA or 0.1 Mils, the reality may be slightly different. Many scopes have actual click values that are slightly higher or lower than the value claimed by the manufacturer. The small variance adds up when you click through a wide range of elevation. In this video, Bryan Litz shows how to verify your true click values using a “Tall Target Test”. The idea is to start at the bottom end of a vertical line, and then click up 30 MOA or so. Multiply the number of clicked MOA by 1.047 to get the claimed value in inches. For example, at 100 yards, 30 MOA is exactly 31.41 inches. Then measure the difference in your actual point of impact.

Coriolis Effect

The Coriolis Effect comes into play with extreme long-range shots. The rotation of the earth actually moves the target a small distance (in space) during the long duration of the bullet’s flight. Bryan Litz notes that, in most common shooting situations inside 1K, Coriolis is not significant. At 1000 yards, the Effect represents less than one click (for most cartridge types). Even well past 1000 yards, in windy conditions, the Coriolis Effect may well be “lost in the noise”. But in very calm conditions, when shooting at extreme ranges, Bryan says you can benefit from adjusting your ballistics solution for Coriolis: “The Coriolis Effect… has to do with the spin of the earth. The consequence of that is that, if the flight time of the bullet gets significantly long, the bullet can have an apparent drift from its intended target. The amount [of apparent drift] is very small — it depends on your latitude and azimuth of fire on the planet.”

About Bryan Litz
Bryan began his career as a rocket scientist, quite literally. He then started Applied Ballistics, the leading company focusing on ballistics science for rifle shooting. A past F-TR Long-Range National Champion and Chief Ballistician for Berger Bullets, knows his stuff. His Applied Ballistics squad was the winning team at the 2017 King of 2 Miles event, and Applied Ballistics has earned major U.S. defense contracts.

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March 22nd, 2022

BC Variance from Bullet Jacket Damage Can Increase Vertical

applied ballistics mobile lab schedule

Here’s a smart tip from Bryan Litz, explaining how damage to a bullet jacket can harm the projectile’s Ballistic Coefficient (BC). This tip is posted on Bryan’s new Bryan Litz Ballistics Facebook page. We recommend you subscribe to that page to access Bryan’s latest informative posts.

Bryan notes: “If the case mouth scratches the bullet when you seat it, the damage can cause the BC to be inconsistent, which shows up as vertical dispersion at long range.

We see this sometimes when running Doppler Radar for competitors at Applied Ballistics Mobile Lab events. If someone is shooting a bullet that typically has a very consistent BC (1% or less) but they’re seeing a higher BC variation, it can be due to the bullets being damaged in the loading process.”

The lead photo above shows the badly-scratched jacket of a bullet seated in a rough-mouthed case. To prevent such jacket damage, one should chamfer, deburr, and smooth case mouths after trimming.

Below is a recorded Doppler radar result showing excessive BC variation. Such variation can increase vertical disperson at long range. This can result in larger group sizes and lower scores.

applied ballistics mobile lab schedule

applied ballistics mobile lab schedule

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March 6th, 2022

The “Mental Game” — Mantras for Competitive Shooting Success

shooting training applied ballistics bryan litz

Bryan Litz Applied Ballistics“Shoot Like a Champion”. Bryan Litz, author of Applied Ballistics for Long-Range Shooting, says he often sees notes like this tucked in shooter’s gear (or taped to an ammo box) at matches. What “marksmanship mantras” do you use? Do you have a favorite quote that you keep in mind during competition?

On the Applied Ballistics Facebook Page, Bryan invited other shooters to post the motivating words (and little reminders) they use in competition. Here are some of the best responses:


    “Shoot 10s and No One Can Catch You…” — James Crofts

    “You Can’t Miss Fast Enough to Win.” — G. Smith

    “Forget the last shot. Shoot what you see!” — P. Kelley

    “Breathe, relax, you’ve got this, just don’t [mess] up.” — S. Wolf

    “It ain’t over ’til the fat lady sings.” — J. McEwen

    “Keep calm and shoot V-Bull.” — R. Fortier

    “Be still and know that I am God[.]” (PS 46:10) — D.J. Meyer

    “Work Hard, Stay Humble.” — J. Snyder

    “Shoot with your mind.” — K. Skarphedinsson

    “The flags are lying.” — R. Cumbus

    “Relax and Breathe.” — T. Fox

    “Zero Excuses.” — M. Johnson

    “SLOW DOWN!” — T. Shelton

    “Aim Small.” — K. Buster

    “Don’t Forget the Ammo!” (Taped on Gun Case) — Anonymous

PARTING SHOT: It’s not really a mantra, but Rick Jensen said his favorite quote was by gunsmith Stick Starks: “Them boys drove a long ways to suck”. Rick adds: “I don’t want to be that guy”, i.e. the subject of that remark.

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February 13th, 2022

G1 vs. G7 Ballistic Coefficients — What You Need to Know

G1 G7 BC drag models

Over the past 12 months, this article was one of the TOP 20 most-read Daily Bulletin features. We’re reprising it today for those who may have missed it the first time. The above diagram comes from a TiborasurasRex YouTube Video comparing G1 and G7 BC models. CLICK HERE to watch the video.

The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.

Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”

The simple answer is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.

G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.

G1 G7 Ballistic coefficients

Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, believes the G7 standard is preferrable for long-range, low-drag bullets: “Part of the reason there is so much ‘slop’ in advertised BCs is because they’re referenced to the G1 standard which is very speed sensitive. The G7 standard is more appropriate for long range bullets. Here’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:

G1 BCs, averaged between 1500 fps and 3000 fps:
Berger 180 VLD: 0.659 lb/in²
JLK 180: 0.645 lb/in²

The reason the BC for the JLK is less is mostly because the meplat was significantly larger on the particular lot that I tested (0.075″ vs 0.059″; see attached drawings).

For bullets like these, it’s much better to use the G7 standard. The following BCs are referenced to the G7 standard, and are constant for all speeds.

G7 BCs:
Berger 180 VLD: 0.337 lb/in²
JLK 180: 0.330 lb/in²

Many modern ballistics programs, including the free online JBM Ballistics Program, are able to use BCs referenced to G7 standards. When available, these BCs are more appropriate for long range bullets, according to Bryan.

[Editor’s NOTE: BCs are normally reported simply as an 0.XXX number. The lb/in² tag applies to all BCs, but is commonly left off for simplicity.]

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February 3rd, 2022

Get Personal Drag Models with Applied Ballistics Mobile Lab

Applied Ballistics Mobile Laboratory 2022

Applied Ballistics (AB) has announced the deployment schedule for the Applied Ballistics Mobile Laboratory during the 2022 shooting season. The Applied Ballistics Crew will be driving the Mobile Lab Truck and Trailer to a number of important shooting events in 2022. At these events you can get a Personal Drag Model (PDM) for your rifle/load based on Doppler Radar testing. The first deployment will be at the Bomber Run match in Indiana on February 18, 2022, just two weeks away. Here is the overall 2022 schedule:

Applied Ballistics Mobile Laboratory 2022

The Applied Ballistics Mobile Lab trailer carries a vast array of equipment including computers, sensors, and advanced Doppler Radar equipment. The Doppler Radar is employed to create custom ballistic profiles (aka “Personal Drag Models”) for shooters at major matches.

Applied Ballistics Mobile Laboratory 2022

Personal Drag Models (PDMs) provide shooters with exact, precise ballistics data for their preferred ammo as fired in their match rifles. This is especially important for rimfire ammo which may start supersonic, then go transonic, and finish well subsonic during much of its flight. Bryan Litz explains: “The Doppler Radar system allows us to track the bullet’s velocity as it flies down-range. As the bullet’s velocity decays, that’s what tells you the ballistic coefficient, the drag, and [other factors].”

About the Applied Ballistics Mobile Lab

Q: What is the basic purpose of the Applied Ballistics Mobile Lab?

Mitchell Fitzpatrick: The Mobile Lab allows us to effectively carry out ballistics testing in the field and at events. It has most of the capabilities of our normal lab, but on wheels.

Q: What hardware and electronics are carried in the Mobile Lab? What are its capabilities?

Bryan Litz: The Mobile Lab will transport most everything that’s in the main lab including the Doppler radar. This rig is new and we haven’t fully outfitted it yet. The load-outs will be somewhat flexible depending on the venue we are supporting.

Applied Ballistics Mobile Laboratory 2022
Applied Ballistics Mobile Laboratory 2022
Applied Ballistics Mobile Laboratory 2022
Applied Ballistics Mobile Laboratory 2022

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January 8th, 2022

Saturday at the Movies: Five Informative Videos to Start 2022

Rodzilla T-Rex front rest shooting F-Class benchrest review

Saturday at the Movies

The online video format is a superior method of presenting information on reloading techniques, rifle maintenance, marksmanship skills, scope operation and much more. But with millions of videos on YouTube, it can be hard to cherry-pick the best videos for serious shooters and competitors. That’s why we offer this Saturday at the Movies Series. Each week we will select a variety of very informative videos by knowledgeable shooters and handloaders. Here are our first five Saturday Select videos for 2022.

Reading the Wind — How to Determine Wind Speed

Keith Glasscock is a top-tier F-Class shooter who has finished second at the F-Class Nationals multiple times. Keith is also a highly-respected wind coach with a background in commercial aviation — so he really understands wind and weather. In this video Keith explains the best techniques for reading the speed of the wind. He notes that you can’t simply rely on the Kestrel in your hand because the wind speed can vary significantly between the firing line and the targets. Keith shows how to look at multiple signs (including flags, grass movement, and mirage) to better understand wind velocity. See more of Keith’s videos on his Winning in the Wind YouTube channel.

Rodzilla T-Rex Front Rest Review — State-of-the-Art Beast


Rodzilla T-Rex front rest shooting F-Class benchrest review

In this video our friend F-Class John reviews the impressive T-Rex front rest from Rodzilla.This recently-introduced joystick front rest from Rodzilla really represents significant innovation. The new T-Rex offers impressive capabilities based on the innovative design by creator Rod Brackage (the “Rod” in Rodzilla”> that can truly take your shooting experience to the next level. F-Class John used this rest in F-Open competition and really likes it. CLICK HERE for John’s full review with three videos and many more photos.

How BAT Actions Are Made and BAT Factory Tour


Note: This has loud music as the start — lower volume if at work.

Ultimate Reloader’s Gavin Gear is a skilled and respected video producer. This Ultimate Reloader video shows how top-end BAT rifle actions are crafted with modern CNC machinery. This is one of Gavin’s most popular videos, with 763,000+ views. If you are interested in accurate rifles for benchrest, F-Class, Long Range, or PRS/NRL you should definitely watch this video. Visit Gavin’s YouTube Channel to see dozens of other informative, well-made videos.

Protect Your Dog’s Hearing with Mutt Muffs

Do you take your dog(s) hunting, or to the shooting range? Well dogs need hearing protection too! Loud gunshots from pistols, rifles, or shotguns can cause permanent hearing damage to your canine. Prevent canine hearing loss with Mutt Muffs — protective earmuffs designed especially for dogs. In the Precision Riflecraft video, the host shows how to fit Mutt Muffs to your dogs and help your canines tolerate the muffs in place. Available in five sizes (XS, S, M, L, XL), these cost under $60 on Amazon.

How to Use Ballistics Solvers — Bryan Litz Lesson

A past national F-TR champion, Bryan Litz is a brilliant engineer and trained rocket scientist. He is also the founder of Applied Ballistics LLC (AB), the world’s leading source of ballistics software. AB software now comes integrated into some Kestrel handheld wind-reading units, with accompanying Applied Ballistics Apps that run on your mobile devices. In this short video Bryan explains how to use ballistics solvers to determine your bullet’s drop and drift at long range. If you don’t have the AB App on your smartphone you can also use the excellent JBM Ballistics Solver, available FREE on the internet.

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December 23rd, 2021

Amazing Applied Ballistics Rimfire Ammo Test — 50 Types Tested

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley
Photo shows Bryan Litz (on right) and tester Mitchell Fitzpatrick. Bryan said: “Only 2,445 rounds to go! We’re testing over 50 ammo types in five different twist barrels… science can be exhausting!”

Do you know the actual BC (Ballistic Coefficient) of your rimfire ammunition? Well Applied Ballistics has the data, thanks to a comprehensive, marathon ammo testing session. Some years back, in an effort to determine the “real world” BCs of various rimfire ammo types, Bryan Litz and his team at Applied Ballistics did an extraordinary, in-depth shooting test. Litz and company tested over fifty types of .22 LR ammo, using five different twist-rate barrels. This was one of the most comprehensive and through rimfire ammo tests ever done.

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley

.22 LR Rimfire Ammunition testingBryan tolds us: “We tested many types of .22 rimfire ammo for the 2nd Edition of the Ballistic Performance of Rifle Bullets book. We used a pair of Oehler chronographs to measure velocity at the muzzle (MV) and velocity at 100 yards.” With these numbers (average and SD) Bryan can calculate G1 BCs for all the 50+ types of rimfire ammo. What’s more, because every sample is shot through five different barrels (each with a different twist rate) Bryan can also determine how velocity is affected by twist rate.

The tests are primarily to determine velocities for BC calculations — this was not an accuracy test. Bryan explains: “Our tests are not really looking at accuracy, mainly because that’s so subjective to different rifles. Our testing is primarily focused on measuring the BC of rimfire rounds from different twist-rate barrels. The MVs and BCs from the different twist test barrels was then published by Applied Ballistics in print books. Bryan Litz told us: “The .22 LR Rimfire data was originally published in Ballistic Performance of Rifle Bullets, 2nd Edition, which is now out of print. The 3rd Edition of that book doesn’t have rimfire data. The rimfire testing results and data were re-published in Modern Advancements in Long Range Shooting – Volume II (along with many other topics).

Bringing Science to the Rimfire World
Bryan’s goal with this project was to increase the rimfire knowledge base: “We hope to give the world of .22 LR rimfire a good dose of science. How is the BC of .22 rimfire ammo affected by barrel twist? Do subsonic rounds have more consistent BCs than supersonic or transonic rounds? What brands have the highest BCs? What brands have the most consistent MVs?”

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley
Data from two Oehler chronographs is recorded in a computer. Ammo samples were tested in five (5) different barrels (of varying twist rates). Give credit to Dane Hobbs who supplied a test rifle, multiple barrels, and most of the ammo types for the test.

.22 LR at 300 Yards?
Bryan also conducted some longer range rimfire tests. His interesting findings have appeared in the Modern Advancements in Long Range Shooting book series. Bryan notes: “While .22 rimfire isn’t typically considered ‘long range’, we were able to consistently hit a two-MOA steel target at 300 yards with the trajectory predicted by AB software and the measured BC of some standard .22 LR rimfire ammo. The info we’re generating may make it possible to push the range of target engagement for a round that’s not seen much advancement in many decades.”

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November 26th, 2021

Twist Rate and Stability — Correcting Common Misconceptions

FirearmsID.com barrel rifling diagram

Understanding Twist: Bullet Stabilization

by Sierra Bullets Ballistic Technician Paul Box for Sierra Bullets Blog.

Based on the questions we get on a daily basis on our 800 (Customer Support) line, twist is one of the most misunderstood subjects in the gun field. So let’s look deeper into this mystery and get a better understanding of what twist really means.

When you see the term 1:14″ (1-14) or 1:9″ twist, just exactly what does this mean? A rifle having a 1:14″ twist means the bullet will rotate one complete revolution every fourteen inches of the barrel. Naturally a 1:9″ turns one time every nine inches that it travels down the barrel. Now, here’s something that some people have trouble with. I’ve had calls from shooters thinking that a 1:14″ twist was faster than a 1:9″ because the number was higher with the 1:14″. The easiest way to remember this is the higher the number, the slower the twist rate is.

Now, the biggest misconception is that if a shooter has a .223 with a 1:8″ twist, his rifle won’t stabilize a 55gr bullet or anything lighter. So let’s look at what is required. The longer a bullet is for its diameter, the faster the twist has to be to stabilize it. In the case of the .223 with a 1:8″ twist, this was designed to stabilize 80gr bullets in this diameter. In truth the opposite is true. A 1:8″ will spin a 55gr faster than what is required in order to stabilize that length of bullet. If you have a bullet with good concentricity in its jacket, over-spinning it will not [normally] hurt its accuracy potential. [Editor’s Note: In addition, the faster twist rate will not, normally, decrease velocity significantly. That’s been confirmed by testing done by Bryan Litz’s Applied Ballistics Labs. There may be some minor speed loss.]

FirearmsID.com barrel rifling diagram
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.

Think of it like tires on your truck. If you have a new set of tires put on your truck, and they balance them proper at the tire shop, you can drive down a street in town at 35 MPH and they spin perfect. You can get out on the highway and drive 65 MPH and they still spin perfect. A bullet acts the same way.

Once I loaded some 35gr HP bullets in a 22-250 Ackley with a 1:8″ twist. After putting three shots down range, the average velocity was 4584 FPS with an RPM level of 412,560. The group measured .750″ at 100 yards. This is a clear example that it is hard to over-stabilize a good bullet.

Twist-rate illustration by Erik Dahlberg courtesy FireArmsID.com. Krieger barrel photo courtesy GS Arizona.
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November 23rd, 2021

Wind Reading Tips from Bryan Litz and Emil Praslick III

Wind reading coaching bryan litz Ben Avery Phoenix wind video

Wind effects are complex. In trying to access wind speeds and angles, you’ll want to watch multiple indicators — mirage, dust, wind-flags, grass movement, and more. You’ll also need to be concerned about wind cycles. In the video below, Bryan Litz talks about variable wind speed along a bullet’s flight path. A respected ballistics guru, Bryan is the founder of Applied Ballistics and a designer of Berger’s Hybrid Match projectiles. He is also a past F-TR National Champion and a High Master Palma ace.

In this video, Bryan discusses how wind effects can vary in intensity at different points along the bullet’s flight path to the target. Sometimes the firing line is sheltered, and the strongest winds come into effect in the middle of the trajectory. Bryan concludes: “Wind matters everywhere … but the best thing you can do is try to get a handle on the wind [velocity and angle] where you are. That may or may not represent the wind down-range — that’s when you have to look downrange and make a judgment[.]”

Litz Competition Tip: 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.

More Wind Tips from Wind Wizard Emil Praslick
In these two short videos, Emil Praslick III, former coach of the USAMU and USA National long range teams, explains how to find the wind direction and how to confirm your no-wind zero. Praslick is widely considered to be one of the best wind coaches in the USA.

When Winds Are EXTREME — Near Gale Force at Ben Avery

This video shows INSANE winds at NBRSA 100/200 Benchrest Nationals. This was filmed at the Ben Avery Range in Phoenix, AZ during the recent NBRSA 100/200 yard National Championships. Extreme to say the least. Based on what we’re seeing here, there are 20-25 mph crosswinds, with gusts to 35 mph — near Gale Force. Video by Hall-of-Fame Benchrest competitor Gene Bukys, whom we sadly lost to COVID last year. RIP Gene.

Texas gunsmith Mike Bryant reports: “This video shows the Unlimited Class 200 at the Nationals in Phoenix. I had three 10-shot groups in the low 2″ range with a 2.228″ being my big group and was glad they weren’t bigger. Thursday and Friday were the worst of the windy days. Unfortunately those were the days for the UL 200 and it was about as windy through most all of the Sporter 200.”

Excellent Wind Reading Resource

The Wind Book for Rifle Shooters covers techniques and tactics used by expert wind-readers. The authors provide a wind-reading “toolbox” for calculating wind speed, direction, deflection and drift. They explain how to read flags and mirage, record and interpret your observations, and time your shots to compensate for wind. Here are two reviews:

This is a must-have book if you are a long-range sport shooter. I compete in F-Class Open and when 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. It covers how to get wind speed/direction from flags, mirage, and natural phenomenon. This is the best book for learning to read wind speed and direction. — Muddler

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September 28th, 2021

King of 2 Miles Event Kicks Off in Raton, New Mexico

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

The 2021 King of 2 Miles ELR competition officially commenced yesterday at the Whittington Center in Raton, New Mexico. This unique event, the “Olympics” of Extreme Long Range (ELR) shooting, attracts many of the best marksmen on the planet, campaigning rifles capable of mind-blowing accuracy at extreme distances. The bullet, barrel, and optics technology on display was impressive — as was the amazing marksmanship. Ryan Cheney is leading the KO2M Qualifications after Day 1&2, shooting perfect 3-for-3s without a miss at 1692, 2097, and 2376 yards, and getting one hit at the most distant 2550-yard target. SEE Day One and Two Results.

Here are some of the cartridges used in ELR Competition. With these high-capacity cartridges, many competitors are using ultra-precision lathe-turned solid bullets.

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range
Big ELR Cartridges left to right: .460 Steyr, .416 Barrett, .375 CheyTac, 33XC, .338 Lapua Magnum, and .300 Remington Ultra Magnum.

Top Results in 2021 Qualifications
Here are the sixteen highest-scoring shooters at the 2021 KO2M match, after two days of qualifications. The Top 16 advance to the Finals tomorrow.

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

Watch K02M Run from 2019 with 360-degree Views
Here is Bryan Litz Shooting K02M in 2019. NOTE, you can slide left/right to get a 360-degree view of the firing line — give it a try! View on Facebook, if 360° movie does not appear on your device.

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

Here are Target Distances and Angles
Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

Paul PhillipsPaul Phillips, 2019 K02M Champion, posted: “I’m very happy with Clay Rhoden with Longshot Cameras and James Devoglaer with KVR Ranch. They performed very well today in qualifications. They hit every plate out to 2550 yards [after the cold bore target]. [This was] their first time at King of 2 Miles!”

Shown below is the ammunition Paul Phillips loaded for his Global Precision Group team using Cutting Edge lathe-turned bullets:

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

Applied Ballistics Brings High-Tech Gear to the KO2M Competition
The Applied Ballistics Team arrived early in Raton to do testing with their high-tech Doppler Radar equipment. This can provide very precise custom ballistics profiles for the ELR rifles. When you’re shooting at these extreme ranges, your come-up tables have to be perfect.

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

“Goooooood Moooooorning New Mexico! It’s a BEAUTIFUL day on the range! We’re setting up the Mobile Lab on the Cooper Range at the NRA Whittington Center and we’ll be hanging out in this gorgeous place.”

Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range
Ko2m king 2 two miles raton new mexico whittington ELR Extreme long range

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August 29th, 2021

Sunday GunDay: King of point28 Miles — Rimfire ELR Match in MN

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

No this isn’t the King of 2 Miles ELR event. But it is the rimfire equivalent — the King of 0.28 Miles (roughly 500 yards). Every year in Minnesota a challenging rimfire match is held at the scenic Rush Lake Range. This combines PRS-style stage shooting out to 300+ yards, along with prone rimfire ELR shooting out to the full “point28 miles”. The 2021 King of point28 Miles match kicked off on August 27, 2021, and concludes today, August 29, 2021. CLICK HERE for LIVE Video from 8/29/21 match, courtesy Applied Ballistics LLC.

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

The King of point28 Miles match features custom-painted steel targets
king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics
Here is an interesting rimfire rig with a unique front end.

Video from 2019 Match (Don’t mind the distorted first frame — the video is excellent!)

king of point28 miles KO2M rimfire .22 LR ELR applied ballisticsTactical Rimfire and .22 LR Rimfire ELR
As conducted in recent years, the King of point28 Miles has been a unique “hybrid” type of competition. The match begins with multiple tactical-style stages with steel targets at various distances. Many of the steel targets are custom-painted, some with elaborate faces. Some stages included PRS/NRL-style barricades or support structures. In past years there have been some specialty targets such as the Accushot One-Shot Challenge (see right) which uses playing cards.

After the shorter stages, there is the namesake “point28 Miles” competition, with dozens of competitors lined up prone shoot distant targets — starting at about 300 yards and moving out progressively to targets 0.28 miles away (about 500 yards). How challenging is that? Consider this — at 500 yards a .22 LR rimfire cartridge may be only traveling 610 fps while a 10mph 90-degree wind can deflect the bullet 8.75 feet off point-of-aim!*

CLICK HERE for LIVE Video from the 8/29/2021 match, ELR stages.

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics
Competitor in Long-Range prone event with Masterpiece Arms (MPA) Chassis rifle.

Custom Personal Drag Models (PDMs) for Rimfire Competitors
The Team from Applied Ballistics was on hand for the King of point28 match. They brought the AB Mobile Lab trailer with its computers, sensors, and advanced Doppler Radar equipment. The Doppler Radar was employed to create custom ballistic profiles (aka “Personal Drag Models”) for 90+ shooters.

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

Personal Drag Models (PDMs) provide shooters with exact, precise ballistics data for their preferred ammo as fired in their match rifles. This is especially important for rimfire ammo which may start supersonic, then go transonic, and finish well subsonic during much of its flight. Bryan Litz explains: “The Doppler Radar system allows us to track the bullet’s velocity as it flies down-range. As the bullet’s velocity decays, that’s what tells you the ballistic coefficient, the drag, and [other factors].”

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics

Prizes Galore for King of point28 Miles Competitors

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics
With a big list of sponsors, the King of point28 Miles Match always has an impressive prize table. Vudoo Gunworks and Accurate Rifle Systems also provided a Match Charity Rifle.

king of point28 miles KO2M rimfire .22 LR ELR applied ballistics
Interesting 4-wheeled range carts from sponsor Range Tactical Gear. Carts are priced from $395 to $650.


* Trajectory calculated with JBM Ballistics based on .22-cal 40gr bullet with 1150 fps muzzle velocity and 0.125 G1 BC. With that BC and MV, the drop at 500 yards from 100-yard zero is 20.1 MOA. Rimfire bullets launched at higher MVs, or which have higher BCs, will exhibit less drop and less wind drift.

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August 27th, 2021

Get Smart — Read FREE Applied Ballistics TECH Articles

Want to improve your understanding of Ballistics, Bullet Design, Bullet Pointing, and other shooting-related tech topics? Well here’s a treasure trove of gun expertise. Applied Ballistics offers dozens of FREE tech articles on its website. Curious about Coriolis? — You’ll find answers. Want to understand the difference between G1 and G7 BC? — There’s an article about that.

“Doc” Beech, technical support specialist at Applied Ballistics says these articles can help shooters working with ballistics programs: “One of the biggest issues I have seen is the misunderstanding… about a bullet’s ballistic coefficient (BC) and what it really means. Several papers on ballistic coefficient are available for shooters to review on the website.”

Litz applied ballistics PDF articles

Credit Shooting Sports USA Editor John Parker for finding this great resource. John writes: “Our friends at Applied Ballistics have a real gold mine of articles on the science of accurate shooting on their website. This is a fantastic source for precision shooting information[.] Topics presented are wide-ranging — from ballistic coefficients to bullet analysis.”

READ All Applied Ballistics Articles HERE »

Here are six (6) of our favorite Applied Ballistics articles, available for FREE to read online. There are dozens more, all available on the Applied Ballistics Education Webpage. After Clicking link, select Plus (+) Symbol for “White Papers”, then find the article(s) you want in the list. For each selection, then click “Download” in the right column. This will send a PDF version to your device.

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August 17th, 2021

Cartridge Base to Ogive (CBTO) Length — Factors to Consider

chamber length loading berger bullets
Here are two different bullet types, seated to the same CBTO length, but different COAL. Note the shiny scratches on the bullets made by the comparator tool which indicates a point on the bullet ogive near where the ogive will engage the rifling.

Berger Bullets COAL length cartridgeEffects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2
by Bryan Litz for Berger Bullets.
Part One of this series focused on the importance of COAL in terms of SAAMI standards, magazine lengths, seating depths, and pressure levels. Another measure of length for loaded ammunition is highly important to precision, namely Cartridge Base to Bullet Ogive Length (CBTO).

Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.
chamber length loading berger bullets

Look at Figure 2. Suppose the bullet was seated out of the case to the point where the base of the bullet’s nose (ogive) just contacted the beginning of the riflings (the lands) when the bolt was closed. This bullet seating configuration is referred to as touching the lands, or touching the riflings and is a very important measurement to understand for precision hand-loading. Due to the complex dynamics of internal ballistics which happen in the blink of an eye, the distance a bullet moves out of the case before it engages the riflings is highly critical to precision potential. Therefore, in order to systematically optimize the precision of his handloads, it’s critically important that the precision hand-loader understands how to alter bullet seating depth in relation to the barrel rifling. Part of the required knowledge is understanding how to accurately and repeatably measure the Cartridge Base To Ogive (CBTO) dimension. This is explained in the FULL ARTICLE.

Bryan Litz offers an extended discussion on how to measure CBTO using different tools and methods, including the Hornady OAL gauge. You can read this discussion in the full article found on the Berger Bullets website. CLICK HERE to Read Full Article.

Why Not Use CBTO as a SAAMI Standard?
If CBTO is so important to rifle accuracy, you might ask, “Why is it not listed as the SAAMI spec standard in addition to COAL?” There is one primary reason why it is not listed in the standard. This is the lack of uniformity in bullet nose shapes and measuring devices used to determine CBTO.

Benefits of Having a Uniform CBTO
There is another aspect to knowing your CBTO when checking your COAL as it pertains to performance. With good bullets, tooling, and carefully-prepared cases you can easily achieve a CBTO that varies less than +/- .001″ but your COAL can vary as much as .025″ extreme spread (or more with other brands). This is not necessarily bad and it is much better than the other way around. If you have a CBTO dimension that varies but your COAL dimension is tight (within +/- .002″) then it is most likely that your bullet is bottoming out inside the seater cone on the bullet tip. This is very bad and is to be avoided. It is normal for bullets to have precisely the same nose shape and it is also normal for these same bullets to have nose lengths that can vary as much as .025″.

Summary of Cartridge Base To Ogive (CBTO) Discussion
Here are four important considerations regarding bullet seating depth as it relates to CBTO:

1. CBTO is a critical measurement to understand for handloaders because it’s directly related to precision potential, and you control it by simply setting bullet seating depth.

2. Tools and methods for measuring CBTO vary. Most of the measurement techniques have pitfalls (which may give rise to inconsistent results) that you should understand before starting out.

3. A CBTO that produces the best precision in your rifle may not produce the best precision in someone else’s rifle. Even if you have the same rifle, same bullets, same model of comparator gauges, etc. It’s possible that the gauges are not actually the same, and measurements from one don’t translate to the same dimension for another.

4. Once you find the CBTO that produces the best precision in your rifle, it’s important to allow minimal variation in that dimension when producing quality handloads. This is achieved by using quality bullets, tooling, and properly preparing case mouths and necks for consistent seating.

CLICK HERE to Read Full Article with More Info
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