“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.
Share the post "Elevate Your “Mental Game” with Marksmanship Mantras"
This report is from Bryan Litz and the ScienceofAccuracy.com website.
As long as there have been rifles, there has been a debate as to how much – if any – the rifle moves prior to the bullet exiting the bore. The first video below shows a Barrett MRAD chambered in .338 Lapua Magnum firing a 300gr Lapua Scenar bullet. Capturing projectiles at 100k+ frames per second allows us to visualize aspects of the firing sequence that are otherwise invisible to the human eye.
Click Video to see barrel with suppressor (on right) move with recoil before bullet exits.
What is clear from this video is that the rifle system is moving rearward while the bullet is traveling through barrel and subsequently through the suppressor. During the “in-bore” portion of bullet travel, any deviation of the muzzle orientation from the initial point of aim can cause a point of impact change. This is because the bullet will exit while the barrel is pointed somewhere different than when the shot was initially fired. Much of the shot’s point-of-aim orientation can be maintained through consistent marksmanship fundamentals and recoil management techniques. However, most shooters are not likely capable of managing it to less than 0.001″ for EVERY shot, especially given on lightweight magnum rifles.
Here’s another example with a 180gr bullet in a Rem 700 BDL .30-06 rifle. “Every time we watch a video like this it reminds us that guns like this, the majority of accuracy and precision come from the gun/sight/support system, not the ammo. When you consider that 0.005″ of muzzle deflection, (orthogonal to the bore) results in ~1.5 moa of dispersion (.75 in any direction) and you see this massive barrel movement prior to bullet exit, it’s clear that the vast majority of dispersion [for typical rifles] is coming from this movement”.
Precision rifle systems, such as benchrest, PRS, and F-Class rifles, tend to minimize the movement away from the bore axis prior to bullet exit to achieve the best possible precision. A common theme among the most precision systems is higher-weight rifles with lower-weight projectiles. This relates to basic physics: Newton’s Third of Motion “For every action, there is an equal and opposite reaction.” With all else held equal, if the rifle weighs more and the bullet weighs less, there is a lower magnitude of motion prior to the bullet leaving the barrel.
In our latest book, Modern Advancements in Long Range Shooting Volume III, Chapter 3 covers the Theory of Precision for Rifles which mathematically describes and estimates the precision potential of rifles based on rifle mass and kinetic energy of the bullet. The chapter includes all the live fire test data to support the theory and great discussion on the testing performed can be found on our podcast at the Science of Accuracy Academy website.
The Applied Ballistics Facebook Page features great, interesting new content posted multiple times each week. This resource features videos, test results, accuracy tips, and samples from Bryan Litz’s excellent books on ballistics and the three volume series on Modern Advancements in Long Range Shooting. Here are some highlights from Applied Ballistics’ Facebook posts from the past two weeks. Plus there’s a discount code, READ2024, that can save you 25% on Applied Ballistics books purchased in the month of March.
.22 LR Super Slow Motion Video — Watch the Bullet!
Watch .22 LR Rimfire Projectile Exiting Rifle Muzzle
This video, filmed with an ultra-high-speed camera, shows the milliseconds in time as a .22-caliber bullet travels the first 11 inches after leaving a .22 LR rifle barrel. Applied Ballistics states: “Notice that the bullet is fully obturated to the internal bore dimension — the step/rebate that exists on the unfired bullet where it meets the case gets expanded (obturated) and doesn’t exist on the fired bullet.”
How Important is Case Fill Ratio — You May Be Surprised
Conventional reloading practice is to select a powder that gives you a good case fill, meaning 90%-100% fill ratio for the cartridge and bullet you’re using. But why?
Some say that a higher fill ratio is good because it prevents the powder from settling differently in the case (which could lead to inconsistent ignition and greater MV SD). This explanation sounds good, and went unchallenged for a long time. However, Applied Ballistics has done some interesting testing that sheds new light on the density issue.
Modern Advancements in Long Range Shooting – Vol. 2 contains the results of Applied Ballistics tests of five different cartridge types — .223 Rem to .338 Lapua — loaded with different powders to produce fill ratios of 80%, 90%, and 100%. The testers wanted to see if 100% fill ratios actually gave better results (lower MV SDs) than the lower fill ratios.
Results of testing 3 different loads in 5 different cartridges — The highest MV SD was in fact measured in an 80% fill ratio load. However, the lowest MV SD was also measured for a different 80% load! Seems like the more we learn, the more questions we have. An informative Applied Ballistics podcast covers the Fill Ratio test. Visit Thescienceofaccuracy.com to access this and interesting podcasts.
EDITOR’s NOTE: There were multiple comments from Facebook readers stating that fill ratios 90% and above worked more consistently for them. And the reloading manuals warn against very low fill ratios.
Get 25% Off Applied Ballistics Books in March 2024
Applied Ballistics, through its Science of Accuracy webstore, is currently offering big savings on its popular books — considered to be the best print resources about rifle accuracy/ballistics ever published. This month you can save 25% on all six Applied Ballistics book titles by respected expert (and past national champion) Bryan Litz. Use Code READ2024 to get 25% of one or more of these books.
Get 25% OFF Applied Ballistics Books! Use code: READ2024 at checkout.
Share the post "Applied Ballistics — Rimfire Video, Fill Ratios, and 25% Off Sale"
The team from Applied Ballistics will offer ballistics services at major matches in 2024. The team will have its advanced Doppler Radar unit which can provide ultra-precise custom ballistic profiles.
Applied Ballistics (AB) has announced the initial deployment schedule for the Applied Ballistics Mobile Laboratory during the 2024 shooting season. The Applied Ballistics Crew will be driving the Mobile Lab Truck and Trailer to a number of important shooting events in 2024. At these events you can get a Personal Drag Model (PDM) for your rifle/load based on Doppler Radar testing. NOTE: You must be actually competing at one of the listed events in order to participate and get a PDM. The first listed deployment will be at the NRL Hunter match in Montana on May 17, 2024. Here is the initial 2024 schedule:
May 17, 2024: Belt, Montana – NRL Hunter
June 7, 2024: Casper, Wyoming – Nightforce ELR
September 11-12, 2024: Grand Junction, Colorado – IPRF World Championships
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.
Share the post "Applied Ballistics Offers Personal Drag Models with Mobile Lab"
Bryan Litz, founder of Applied Ballistics LLC, has a very informativeFacebook page where he regularly posts useful ballistics info and shooting tips. We recommend that Facebook users check out the Bryan Litz Ballistics Facebook page. Here is one interesting example from that page. Bryan analyzes the Crosswind Weighting Factor (CWF). The Crosswind Weighting Factor (CWF) shows where a bullet’s trajectory is most susceptible to wind. By understanding CWF, shooters can better predict how wind affects bullet flight, especially at extreme ranges, when the projectile has gone transonic.
Crosswind Weighting Factor (CWF) graphs show where bullet trajectories are most susceptible to wind.
Where does the wind have the most effect?
At the shooter?
At the target?
Halfway?
Bryan Litz explains: “Out through the supersonic range, the CWF is maximum at the shooter. However as the trajectory extends into transonic, the max CWF gets pushed down range. That’s because the greatest segments of lag time in the bullets trajectory are at transonic where the drag coefficient is maximized around Mach 1.” [Editor: So if your bullet stays fully supersonic during its flight to your target, you can normally expect the CWF to be highest at your shooting station. But once the projectile drops into transonic speeds then the situation changes.]
Get More Tips on Bryan Litz Ballistics Facebook Page
This post is from the new Bryan Litz Ballistics Facebook page. You can bookmark that page at www.Facebook.com/BryanLitzBallitics. Facebook users will want to check that page regularly for other advice from Bryan, American’s leading Ballistics expert and founder of Applied Ballistics LLC.
Applied Ballistics also offers a noteworthy online training operation — The Science of Accuracy Academy. This will include podcasts, exclusive seminars, and access to the latest Applied Ballistics research.
Share the post "Crosswind Weighting Factor Explained by Bryan Litz"
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 (or on a long-range hunt). 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 of Applied Ballistics 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. If, for example, your point of impact is 33 inches, then you are getting more than the stated MOA with each click (assuming the target is positioned at exactly 100 yards).
How to Perform the Tall Target Test
The tall target test determines if your scope is giving you the proper amount of adjustment. For example, when you dial 30 MOA, are you really getting 30 MOA, or are you getting 28.5 or 31.2 MOA? The only way to be sure is to verify, don’t take it for granted! Knowing your scopes true click values insures that you can accurately apply a ballistic solution. In fact, many perceived inaccuracies of long range ballistics solutions are actually caused by the scopes not applying the intended adjustment. In order to verify your scope’s true movement and calculate a correction factor, follow the steps in the Tall Target Worksheet. This worksheet takes you thru the ‘calibration process’ including measuring true range to target and actual POI shift for a given scope adjustment.
NOTE: When doing this test, don’t go for the maximum possible elevation. Do NOT max out the elevation knob, running it to the top stop. Bryan Litz explains: “It’s good to avoid the extremes of adjustment when doing the tall target test. I don’t know how much different the clicks would be at the edges, but they are not the same.”
Tall Target Test For Milrad Scopes with B2B Target
This Precision Rifle Network video shows how to do a scope-tracking test using the pre-printed Sniper’s Hide Tall Target from Box to Bench Precision (B2B). With the primary line divisions in MILs, this printed target is perfect for Milliradian scopes. From bottom of the vertical line to the top there are 10 mils (36 inches) of travel. The markings are high contrast to make the testing easier.
In this video, there are some very helpful tips on setting up the target frame correctly and making sure the Tall Target is perfectly vertical. A plumb line can help. In this video the vertical tracking of a Burris XTR III 5.5-30x56mm scope is tested. Actual testing begins at 7:20 time-mark. The Precision Rifle Network has many other informative videos, with a new video released every week.
Should You Perform a WIDE Target Test Too?
What about testing your windage clicks the same way, with a WIDE target test? Bryan Litz says that’s not really necessary: “The wide target test isn’t as important for a couple reasons. First, you typically don’t dial nearly as much wind as you do elevation. Second, your dialed windage is a guess to begin with; a moving average that’s different for every shot. Whereas you stand to gain a lot by nailing vertical down to the click, the same is not true of windage. If there’s a 5% error in your scope’s windage tracking, you’d never know it.”
Verifying Scope Level With Tall Target Test
Bryan says: “While setting up your Tall Target Test, you should also verify that your scope level is mounted and aligned properly. This is critical to insuring that you’ll have a long range horizontal zero when you dial on a bunch of elevation for long range shots. This is a requirement for all kinds of long range shooting. Without a properly-mounted scope level (verified on a Tall Target), you really can’t guarantee your horizontal zero at long range.”
NOTE: For ‘known-distance’ competition, this is the only mandatory part of the tall target test, since slight variations in elevation click-values are not that important once you’re centered “on target” at a known distance.
Share the post "Confirm Your Scope Click Values with Tall Target Test"
The USAMU has published a “how-to” article about bullet sorting. While many of us may sort bullets by base-to-ogive length (and/or weight), the USAMU story explores the “how and why” of sorting bullets by Overall Length (OAL). Read the article highlights below, and make your own decision as to whether OAL sorting is worth the time and effort. Bryan Litz of Applied Ballistics says that sorting by OAL is not a bad idea, but base-to-ogive bullet sorting probably represents a better investment of your time.
Bullet Sorting by Overall Length
We’d like to share a specialized handloading technique which we’ve long found beneficial to our long-range (600 yards and beyond) accuracy. Sorting of bullets for extreme long range (LR) accuracy is not difficult to do, but some background in theory is needed.
Here at USAMU’s Handloading Shop, we only sort individual bullets for the most demanding Long-Range applications and important competitions. Only the most accurate rifles and shooters can fully exploit the benefits of this technique. The basic sorting process involves measuring the Overall Length (OAL) of the bullets, and grouping them in 0.001″ increments. It’s not unusual to find lots of match bullets that vary as much as 0.015″-0.020″ in length throughout the lot, although lots with much less variation are seen as well. Even in bullet lots with 0.015″ OAL variation, the bullet base-to-ogive length will show much less variation. Hence, our basic sort is by bullet OAL. One obvious benefit of sorting is easily seen in the attached photo. The few bullets that are VERY different from the average are culled out, reducing probable fliers.
How does one know what OAL increments to use when sorting? The answer is simple. As each lot of bullets is unique in its OAL distribution, it’s best to sample your bullet lot and see how they are distributed. In the attached photo, you will see a set of loading trays with a strip of masking tape running along the bottom. Each vertical row of holes is numbered in 0.001″ increments corresponding to the bullets’ OAL. A digital caliper makes this task much easier. As each bullet is measured, it is placed in the line of holes for its’ OAL, and gradually, a roughly bell-shaped curve begins to form.
Note that near the center, bullets are much more plentiful than near the edges. At the extreme edges, there are a few that differ markedly from the average, and these make great chronograph or sighting-in fodder. We recommend using a sample of 200 bullets from your lot, and 300 is even better. Some bullet lots are very consistent, with a tall, narrow band of highly-uniform bullets clustered together over just a few thousandths spread. Other lots will show a long, relatively flat curve (less uniform), and you may also see curves with 2 or more “spikes” separated by several 0.001″ OAL increments.
Bullet Sorting — OAL vs. Base-to-Ogive vs. Weight
Expert advice from Bryan Litz, Applied Ballistics
I’m often asked what is a the best measure to sort bullets by, and the answer (to this and many other questions in ballistics) is: it depends.
Choosing to sort by overall length (OAL), base to ogive (BTO), bearing surface, weight, etc. can get overwhelming. Shooters typically look for something they can measure, which shows a variation and sort by that. It’s common for dimensional variations to correlate. For example, bullets which are longer in OAL are typically also shorter in BTO, and have longer noses. All these are symptoms of a bullet that was pushed a little further into the pointing die, or possibly had more than average lube while being swaged. So in essence, if you sort by BTO, you’re measuring one symptom which can indicate a pattern in the bullets shape.
So, the question still stands — what should you measure? You’ll always see more variation in OAL than BTO, so it’s easier to sort by OAL. But sometimes the bullet tips can be jagged and have small burrs which can be misleading. Measuring BTO will result in a lower spread, but is a more direct measure of bullet uniformity.
Then there’s the question of; how much variation is too much, or, how many bins should you sort into? Shooters who see 0.025” variation in BTO may choose to sort into 5 bins of 0.005”. But if you have only 0.005” variation in the box, you’ll still sort into 5 bins of 0.001”. What’s correct? You have to shoot to know. Live fire testing will answer more questions, and answer them more decisively than any amount of discussion on the subject. The test I recommend is to identify bullets on the extreme short end of the spectrum, and some on the extreme long end. Load at least 10 rounds of each, and take turns shooting 5-shot groups with them. If there is a difference, it will be evident. The results of the testing will answer your question of: should I sort based on X, Y, or Z?”
You can read more discussions on this and other similar subjects in our Accurateshooter.com Shooters’ Forum. Here’s a link to a thread discussing bullet sorting: Bullet Sorting Thread
Share the post "How to Sort Bullets: OAL vs. Base-to-Ogive vs. Weight"
The Coriolis Effect comes into play with extreme long-range shots like this (2100 yards at Raton, New Mexico). The rotation of the earth actually moves the target a small distance (in space) during the long duration of the bullet’s flight.
When you’re out at the range, the Earth seems very stable. But it is actually a big sphere zooming through space while spinning around its axis, one complete turn every 24 hours. The rotation of the earth can create problems for extreme long-range shooters. During extended bullet flight times, the rotation of the planet causes an apparent deflection of the bullet path over very long distances. This is the ballistics manifestation of the Coriolis Effect.
Bryan Litz of Applied Ballistics discusses and explains the Coriolis Effect in his Ballistics Books and Seminars. Bryan notes that Coriolis is “a very subtle effect. People like to make more of it than it is because it seems mysterious.” In most common shooting situations inside 1K, Coriolis is not important. 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.
Bryan explains: “The Coriolis Effect… has to do with the spin of the earth. You are basically shooting from one point to another on a rotating sphere, in an inertial reference frame. 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.”
Coriolis is a very subtle effect. With typical bullet BCs and velocities, you must get to at least 1000 yards before Coriolis amounts to even one click. Accordingly, Bryan advises: “Coriolis Effect is NOT something to think about on moving targets, it is NOT something to think about in high, uncertain wind environments because there are variables that are dominating your uncertainty picture, and the Coriolis will distract you more than the correction is worth.”
“Where you could think about Coriolis, and have it be a major impact on your hit percentage, is if you are shooting at extended range, at relatively small targets, in low-wind conditions. Where you know your muzzle velocity and BC very well, [and there are] pristine conditions, that’s where you’re going to see Coriolis creep in. You’ll receive more refinement and accuracy in your ballistics solutions if you account for Coriolis on those types of shots. But in most practical long-range shooting situations, Coriolis is NOT important. What IS important is to understand is when you should think about it and when you shouldn’t, i.e. when applying it will matter and when it won’t.”
Share the post "Long Range Shooting on a Spinning Planet — The Coriolis Effect"
Bryan Litz and The Science of Accuracy Academy has done a Podcast with vital information for all handloaders. This Podcast examines the effects of humidity variances on powder. Bryan notes: “If you want to know how much this can matter, we’re talking up to 200 fps difference for the same load of H4350 in 6.5 Creedmoor” at opposite extremes of humidity.
Bryan adds that “Most shooters don’t realize what a big deal this can be — it overshadows many of our efforts to make consistent velocity and hit targets. This can happen in loaded rounds not just for hand loading where you expose powder to ambient humidity. This is especially important for hunters considering the range of environments hunting ammo goes through.”
$20 OFF The Science of Accuracy Academy Products
As a Holiday Season promotion, The Science of Accuracy Academy Store is offering $20 Off orders $100 or more, now through the end of 2023. Save on Bryan Litz’s six impressive books about Ballistics, Bullet Performance, and Long Range Shooting. The Berger Bullets Reloading Manual is also discounted. And there are Berger Bullets and reloading items on sale. Use Discount Code JOLLY23 for the $20 savings.
In addition you can get your own subscription to the Academy, allowing you to access all podcasts, exclusive videos, learning resources, and bullet data sheets.
Share the post "Effects of Humidity on Powder Performance — Podcast INFO"
Applied Ballistics Founder Bryan Litz and Former USAMU and Team USA coach Emil Praslick III share their wisdom in an informative Guns Magazine Podcast. Along with being a true ballistics guru, Bryan Litz is an outstanding competitive shooter, having won F-TR National Championships, and both Sling and F-TR divisions at the Berger SW Nationals, along with many other matches. Emil is considered one of the world’s great wind-readers and team coaches, having coached 20+ championship teams.
Guns Magazine podcast host Brent Wheat asks Bryan and Emil about multiple topics including: exterior ballistics, bullet design, wind reading, ballistic solvers, BC myths, and more.
Brent reports: “Together, Bryan and Emil understand what happens from the time a bullet leaves the muzzle until it impacts the target, including the atmospheric affects along the way. Grab a pencil, listen in, and get ready to take notes.”
This Long Range Grad School podcast features Berger’s Chief Ballistician, Bryan Litz, and Berger’s Emil Praslick. Both have extensive long range competitive shooting experience, with championship titles (as shooter and/or coach) in a multitude of long range disciplines. CLICK arrow below to start podcast audio:
Emil Praslick (left) confers with Bryan Litz (right) at King of 2 Miles ELR Event.
In this Video Emil Praslick explains his methods for determining wind direction.
Bryan Litz coaching Team USA in Canada using a WIND PLOT.
Share the post "Long Range Experts Podcast — Bryan Litz and Emil Praslick"
Figure 1. When the bullet is seated farther out of the case, there is more volume available for powder. This enables the cartridge to generate higher muzzle velocity with the same pressure.
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 1 by Bryan Litz forBerger Bullets.
Many shooters are not aware of the dramatic effects that bullet seating depth can have on the pressure and velocity generated by a rifle cartridge. Cartridge Overall Length (COAL) is also a variable that can be used to fine-tune accuracy. It’s also an important consideration for rifles that need to feed rounds through a magazine. In this article, we’ll explore the various effects of COAL, and what choices a shooter can make to maximize the effectiveness of their hand loads.
Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI)
Most loading manuals (including the Berger Manual), present loading data according to SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) standards. SAAMI provides max pressure, COAL and many other specifications for commercial cartridges so that rifle makers, ammo makers, and hand loaders can standardize their products so they all work together. As we’ll see later in this article, these SAAMI standards are in many cases outdated and can dramatically restrict the performance potential of a cartridge.
Bullet seating depth is an important variable in the accuracy equation. In many cases, the SAAMI-specified COAL is shorter than what a hand loader wants to load their rounds to for accuracy purposes. In the case where a hand loader seats the bullets longer than SAAMI specified COAL, there are some internal ballistic effects that take place which are important to understand.
Effects of Seating Depth / COAL on Pressure and Velocity
The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long. In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short.
When you think about it, it makes good sense. After all, when you seat the bullet out longer and leave more internal case volume for powder, you’re effectively making the cartridge into a bigger cartridge by increasing the size of the combustion chamber. Figure 1 illustrates the extra volume that’s available for powder when the bullet is seated out long.
Before concluding that it’s a good idea to start seating your bullets longer than SAAMI spec length, there are a few things to consider.
Geometry of a Chamber Throat
The chamber in a rifle will have a certain throat length which will dictate how long a bullet can be loaded. The throat is the forward portion of the chamber that has no rifling. The portion of the bullet’s bearing surface that projects out of the case occupies the throat (see Figure 2).
The length of the throat determines how much of the bullet can stick out of the case. When a cartridge is chambered and the bullet encounters the beginning of the rifling, known as the lands, it’s met with hard resistance. This COAL marks the maximum length that a bullet can be seated. When a bullet is seated out to contact the lands, its initial forward motion during ignition is immediately resisted by an engraving force.
Seating a bullet against the lands causes pressures to be elevated noticeably higher than if the bullet were seated just a few thousandths of an inch off the lands.
A very common practice in precision reloading is to establish the COAL for a bullet that’s seated to touch the lands. This is a reference length that the hand loader works from when searching for the optimal seating depth for precision. Many times, the best seating depth is with the bullet touching or very near the lands. However, in some rifles, the best seating depth might be 0.100″ or more off the lands. This is simply a variable the hand loader uses to tune the precision of a rifle.
This is one of the very best books ever published about Long Range shooting. Based on sophisticated testing and research, this 356-page hardcover from Applied Ballistics offers important insights you won’t find anywhere else. Modern Advancements in Long Range Shooting – Volume II, a major treatise from Bryan Litz, is chock full of information, much of it derived through sophisticated field testing. As Chief Ballistician for Berger Bullets (and a trained rocket scientist), author Bryan Litz is uniquely qualified. Bryan is also an ace sling shooter and a past F-TR National Champion. Moreover, Bryan’s company, Applied Ballistics, has been a leader in the Extreme Long Range (ELR) discipline.
AUDIO FILE: Bryan Litz Talks about Modern Advancements in Long Range Shooting, Volume 2. (Sound file loads when you click button).
Volume II of Modern Advancements in Long Range Shooting ($44.95) contains all-new content derived from research by Applied Ballistics. Author Bryan Litz along with contributing authors Nick Vitalbo and Cal Zant use the scientific method and careful testing to answer important questions faced by long range shooters. In particular, this volume explores the subject of bullet dispersion including group convergence. Advanced hand-loading subjects are covered such as: bullet pointing and trimming, powder measurement, flash hole deburring, neck tension, and fill ratio.
Each topic is explored with extensive live fire testing, and the resulting information helps to guide hand loaders in a deliberate path to success. The current bullet library of measured G1 and G7 ballistic coefficients is included as an appendix. This library currently has data on 533 bullets in common use by long range shooters.
Bryan tells us that one purpose of this book is to dispel myths and correct commonly-held misconceptions: “Modern Advancements in Long Range Shooting aims to end the misinformation which is so prevalent in long range shooting. By applying the scientific method and taking a Myth Buster approach, the state of the art is advanced….”
Bullet Dispersion and Group Convergence
Part 1 of this Volume is focused on the details of rifle bullet dispersion. Chapter 1 builds a discussion of dispersion and precision that every shooter will benefit from in terms of understanding how it impacts their particular shooting application. How many shots should you shoot in a group? What kind of 5-shot 100 yard groups correlate to average or winning precision levels in 1000 yard F-Class shooting?
Chapter 2 presents a very detailed investigation of the mysterious concept of group convergence, which is the common idea that some guns can shoot smaller (MOA) groups at longer ranges. This concept is thoroughly tested with extensive live fire, and the results answer a very important question that has baffled shooters for many generations.
Part 2 of this Volume is focused on various aspects of advanced hand-loading. Modern Advancements (Vol. II) employs live fire testing to answer the important questions that precision hand loaders are asking. What are the best ways to achieve MVs with low ES and SD? Do flash hole deburring, neck tension, primer selection, and fill ratio and powder scales sensitivity make a difference and how much? All of these questions are explored in detail with a clear explanation of test results.
One of the important chapters of Part 2 examines bullet pointing and trimming. Applied Ballistics tested 39 different bullet types from .224 through .338 caliber. Ten samples of each bullet were tested for BC in each of the following configurations: original out of the box, pointed, trimmed, pointed and trimmed. The effect on the average BC as well as the uniformity in BC was measured and tabulated, revealing what works best.
Part 3 covers a variety of general research topics. Contributing author Nick Vitalbo, a laser technology expert, tested 22 different laser rangefinders. Nick’s material on rangefinder performance is a landmark piece of work. Nick shows how shooters can determine the performance of a rangefinder under various lighting conditions, target sizes, and reflectivities.
Chapter 9 is a thorough analysis of rimfire ammunition. Ballistic Performance of Rifle Bullets, 2nd Edition presented live fire data on 95 different types of .22 rimfire ammunition, each tested in five different barrels having various lengths and twist rates. Where that book just presented the data, Chapter 9 of this book offers detailed analysis of all the test results and shows what properties of rimfire ammunition are favorable, and how the BCs, muzzle velocities and consistency of the ammo are affected by the different barrels.
Chapter 10 is a discussion of aerodynamic drag as it relates to ballistic trajectory modeling. You will learn from the ground up: what an aerodynamic drag model is, how it’s measure and used to predict trajectories. Analysis is presented which shows how the best trajectory models compare to actual measured drop in the real world.
Finally, contributing author Cal Zant of the Precision Rifle Blog presents a study of modern carbon fiber-wrapped barrels in Chapter 11. The science and technology of these modern rifle barrels is discussed, and then everything from point of impact shift to group sizes are compared for several samples of each type of barrel including standard steel barrels.
Share the post "Great Book — Modern Advancements in Long Range Shooting II"
“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?
Some say that a higher fill ratio is good because it prevents the powder from settling differently in the case (which could lead to inconsistent ignition and greater MV SD). This explanation sounds good, and went unchallenged for a long time. However, Applied Ballistics has done some interesting testing that sheds new light on the density issue.
Verifying Scope Level With Tall Target Test
When you’re out at the range, the Earth seems very stable. But it is actually a big sphere zooming through space while spinning around its axis, one complete turn every 24 hours. The rotation of the earth can create problems for extreme long-range shooters. During extended bullet flight times, the rotation of the planet causes an apparent deflection of the bullet path over very long distances. This is the ballistics manifestation of the 
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 1
Part 2 of this Volume is focused on various aspects of advanced hand-loading. Modern Advancements (Vol. II) employs live fire testing to answer the important questions that precision hand loaders are asking. What are the best ways to achieve MVs with low ES and SD? Do flash hole deburring, neck tension, primer selection, and fill ratio and powder scales sensitivity make a difference and how much? All of these questions are explored in detail with a clear explanation of test results.
