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 As we’ll see later in this article, these SAAMI standards are in many cases outdated and can dramatically restrict the performance potential of a cartridge.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.
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Powder Valley has added Norma products to its extensive inventory of ammunition, reloading components, tools, and shooting accessories. Powder Valley is now carrying Norma products for shooters and handloaders. Norma ammo and components are developed with the high quality raw materials and tight tolerances to ensure long life and accuracy.
About Norma Precision AB
Dedicated to outfitting shooting enthusiasts with quality products since 1902, Norma started out in a small Swedish town and is now a top global brand boasting more than 350 employees, most of whom are hunters, shooters, and reloaders themselves. For hunting and target shooting applications Norma manufactures many millions of rounds annually for 100+ different cartridge types.
VERY Informative Video Show Cartridge Brass and Ammunition Production:
Here’s a cool video showing how bullet, brass, and ammunition are produced at the Norma Precision AB factory. You can see how cartridges are made starting with brass disks, then formed into shape through a series of processes, including “hitting [the cup] with a 30-ton hammer”. After annealing (shown at 0:08″), samples from every batch of brass are analyzed (at multiple points along the case length) to check metal grain structure and hardness. Before packing, each case is visually inspected by a human being (3:27″ time-mark). The video also shows how bullets are made from jackets and lead cores. Finally, you can watch the loading machines that fill cases with powder, seat the bullets, and then transport the loaded rounds to the packing system.
12 Days Of Christmas Contest at Powder Valley
Beginning Monday, December 4, 2023, Powder Valley has been running a major give-away contest, with prize products from a different maker each day. Today, 12/6/23, Berry’s Bullets are the Prize. And, TAKE NOTE readers, tomorrow 12/7/2023 Lapua, Berger, and Vihtavuori products are the Daily Contest Prize. If you need Lapua Brass, Berger Bullets, or VV powder, be sure to enter before end of day 12/7/2023. The 12 prizes vary by day and by value. Each day’s prize will be posted on Facebook and Instagram. WINNER SELECTION: A random drawing will be conducted the following day by Sponsor or its designated representatives. The Sweepstakes began on 12/4/23 and ends on 12/15/23.
About Powder Valley Powder Valley began in 1984 as Dexter Automotive, the first master distributor of Accurate powder. In 2000, Bryan and Noel Richardson purchased the company and moved operations to Winfield, Kansas with a focus on providing the finest in reloading components at the best possible price. Powder Valley expanded its vision to offer every type of powder and primer available so reloaders would have a single shopping source. Since then, Powder Valley has grown into the largest distributor of canister powder in the United States and currently carries an ever-expanding offering of high-quality bullets, brass, wads, shot, gun care items, and ammunition at an excellent value.
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We congratulate John Masek (F-Open) and Keith Trapp (F-TR), the 2023 NRA F-Class Mid-Range National Champions. The Mid-Range Nationals were held at the Ben Avery Range outside Phoenix, Arizona, and the F-Class Long Range Nationals continue November 2 through November 5, 2023. Keith’s 2023 Mid-Range title was his second big win in a row — Keith won the Long-Range F-TR Championship in 2022.
2023 F-Class Mid-Range National Champions Keith Trapp (L) and John Masek (R).
We were particularly pleased to see our colleague John Masek earn this major victory. John helps AccurateShooter.com with product tests/reviews, and John works on our Deals of the Week features. John also has a popular F-Class John YouTube Channel with videos we frequently feature. And you can see John’s content on his new website FClassJohn.com. CLICK HERE to access John’s videos and product tests.
John Masek Wins His First Nationals
John finished with a very impressive 1774-95X score, followed by Jason Simes (1772-84X) and Norm Harrold (1768-99X). John shot very well in difficult, windy conditions, finishing with not just the highest Grand Aggregate score, but the second highest X-Count (after Norm Harrold). This is a big win for John, his first-ever National title. No one has worked harder to raise his game through advanced reloading processes and lots of practice both with centerfire and rimfire rifles.
Forum member and fellow F-Class competitor David Joe praised John’s performance: “Hey John, great wind calling this week, congratulations! Who needs Long-Range with wind like that. What a close and hard won contest! Great scores today!”
In the F-TR Division, Keith Trapp took top honors with a 1776-87X score, followed by Tracy Hogg (1767-70X), and James Crofts (1762-67X). Keith, a proven F-TR superstar, also won the F-TR 1000-yard Nationals at Ben Avery in 2022.
Here’s an insightful interview with John Masek and fellow F-Open ace and YouTube host Erik Cortina:
And here is a video F-Class John produced at last year’s Long-Range (1000-yard) F-Class Championship. This was also held at the Ben Avery Range in Arizona.
Destiny Fulfilled: Before John left his Oregon home for the 2023 F-Class Nationals, this Editor spoke to John on the telephone. I said “Good luck John, I think you’re due to stand on the podium and hold a trophy.” That prediction proved prophetic. We are glad to see our friend and colleague John Masek now hold the title of NRA F-Class Open Mid-Range National Champion!
Shown above is John’s 7 PRCW F-Open Rifle. This features a Borden BRMXD action, X-Ring stock, and Flavio Fare trigger. On top is the 8-80x56mm March Majesta scope, a very advanced new optic. The rifle is chambered for the 7mm PRCW cartridge. John loads with Lapua brass, Vihtavuori N555 powder, and Berger 180gr Hybrid bullets.
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Ever wondered how factory ammunition is produced, from start to finish? How are brass cases made, how are bullets created, and how are finished cartridges produced on automated assembly lines? Today’s video showcase features six major factories that, collectively, produce bullets, powder, and finished ammo. We start with the Berger Bullet plant, follow by Vihtavuori powder production in Europe. Then we show the Remington (now Vista Outdoor) ammo plant in Utah, along with a Federal plant that produces rimfire ammunition. Last but not least, there’s an excellent, very informative video from the Norma ammo factory, plus a Hornady ammo plant video.
Bullets being seating at Hornady ammo factory.
Berger Bullets Factory Tour — Made in USA
In this video, Recoil TV takes a behind-the-scenes look at Berger Bullets, and how the outstanding, match-winning Berger bullets are created. The video covers the entire process — from raw materials, to the placement of bullet cores inside jackets, to the final ultra-consistent and uniform projectiles. To see the complete line of Berger Bullets, with full Ballistic data, visit BergerBullets.com
Vihtavuori Powder Production in Europe
Vihtavuori produces some of the most consistent, high-quality powder on the planet. Vihtavuori powders have been used to set world records and win countless championships in multiple disciplines. This excellent video goes inside Vihtavuori’s European production centers. It is really fascinating — you see how extruded powder starts with long spaghetti-like strings, before being finalized into the tiny sticks that we load.
Along with the powder production process, this video includes the entire VV production line, so you see how powder bottles are filled with powder and the tops of the bottles are secured by automated machines.
Remington Ammo Factory (Now Operated by Vista Outdoor)
This SHWATteam video visits the Remington ammunition plant in Arkansas. Vista Outdoor, the company that produces Federal, Speer and CCI ammo, purchased Remington’s ammunition business in Lonoke, Arkansas. Including the new high-tech plant in the back, this facility has the equivalent of 13+ football fields (1200 acres) under roof at its ammo plant, with over 1100 employees. Production capacity is impressive. When running at maximum output, this Remington ammo plant can crank out a staggering 7,000,000+ rounds every day. To produce that volume of ammunition, the facility needs a huge amount of resources: one million pounds of copper per month and 124,000 pounds of lead per day. Remington started manufacturing ammunition at this Lonoke facility in 1970, but some of the machines have been churning out ammo since long before.
Norma Factory Tour
Guys — honestly, if you do anything today on this site, watch this video. You won’t be disappointed. Guaranteed. This is a very informative (and surprisingly entertaining) video. Every serious hand-loader should watch this video to see how cartridge cases are made. The camera work and editing are excellent — there are many close-ups revealing key processes such as annealing and head-stamping.
VERY Informative Video Show Cartridge Brass and Ammunition Production:
Norma has released a fascinating video showing how bullets, brass, and ammunition are produced at the Norma Precision AB factory which opened in 1902. You can see how cartridges are made starting with brass disks, then formed into shape through a series of processes, including “hitting [the cup] with a 30-ton hammer”. After annealing (shown at 0:08″), samples from every batch of brass are analyzed to check metal grain structure and hardness. Before packing, each case is visually inspected by a human being (3:27″ time-mark).
Federal Rimfire Ammunition Production
Field & Stream Tours Federal Ammo Plant in Minnesota
A reporter for Field & Stream recently got a chance to tour the Federal ammunition production facility in Anoka, Minnesota. This large plant produces both rimfire and centerfire ammunition. While touring the plant, the reporter was allowed to capture video showing the creation of .22 LR rounds from start to finish. This is a fascinating video, well worth watching. Watch and learn how rimfire ammo is made.
Note to Viewers — After Starting Video, Click Speaker Icon to HEAR audio!
This revealing video shows all phases of .22 LR ammo production including cupping, drawing, annealing, washing, drying, head-stamping, priming, powder charging, bullet seating, crimping, waxing, inspection, and final packaging. We recommend you watch the video from start to finish. You’ll definitely learn some new things about rimfire ammo.
Hornady Ammunition Factory
If you wonder how ammo is made, starting with raw metal, check out this video from Hornady. It shows how bullet jackets are formed from copper, followed by insertion of a lead core. The jacket is then closed up over the core with the bullet taking its final shape in a die (a cannelure is applied on some bullet types). Next the video shows how cartridge brass is formed, starting with small cups of brass. The last part of the video shows how cases are primed and filled with powder, and how bullets are seated into the cases, using an automated process on a giant assembly-line.
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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.
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2 by Bryan Litz forBerger 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.
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.
A carpet is used up front for smoother tracking with the Joy-Pod’s flat, ski-style feet. The arms of the Joy-Pod were painted to match the stock. The rear bag features low-drag material on the ears.
F-Class competition grows in popularity every year. Unlike F-Open, the F-TR (Target Rifle) class is limited to the .223 Remington (5.56×45) or .308 Winchester (7.62×51) chamberings. F-TR rifles also use bipods rather than a front rest. But these are no ordinary Harris-style bipods. Modern F-TR bipods have a wide footprint for added stability and many F-TR shooters favor SEB Co-Axial joystick bipods (aka “Joy-Pods”). Today we are featuring an F-TR rig that showcases the types of components, and accessories used by top F-TR competitors — including a coaxial bipod and Labradar Chronograph. If you’re considering getting started in the F-TR game, take a close look at this modern F-TR build from Forum member DM.Oakes.
Modern F-TR Rig with Borden Action, Krieger Barrel, and SEB Joy-Pod
This handsome .308 Win F-TR rig features a smooth-running Borden BRM action, 30-inch 1:10″-twist Krieger barrel, and an X-Ring Laminated Wood stock. Up front is a coaxial “Joy-Pod” joystick bipod. This is a state-of-the art, wide footprint bipod used by many competitors at the Worlds in Canada. The long joystick allows the “driver” to quickly adjust both elevation and windage in a smooth, continuous motion. The Joy-Pod can be adjusted so it will hold setting during the shot — you don’t have to “hard-hold” the joystick. Many shooters let the joystick slide through their fingers as the rifle moves back on recoil. With a little practice (and careful placement of the rear sand-bag), the tracking is excellent and you can slide the gun right back to point of aim after each shot.
This F-TR rifle is shown during load testing with a LabRadar chronograph.
» Full LabRadar Field Test/Review by Ray Gross
If you are considering purchasing a LabRadar Chronograph system, we strongly suggest you read the very thorough and informative LabRadar Review by Ray Gross, past Captain of the USA F-TR team. Ray notes: “It takes me about 3 minutes to set up [my LabRadar] at the range. Because there are no downrange screens, I do not have to hold up other shooters on the range like I would when setting up a traditional chronograph. The convenience alone will mean that I will use it more often than my old chronograph. Every time I take it out, I enjoy it a little bit more.”
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Over the past 12 months, this article was one of the TOP TEN 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.
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 preferable 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.
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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Emil Praslick III is widely recognized as one of the greatest wind wizards on the planet — a master at identifying wind value and direction, and predicting wind cycles. As coach of the USAMU and top civilian teams, Emil has helped win many high-level championships. In the three videos we feature today, Emil, who works with Capstone Precision Group (Berger, Lapua, SK, Vihtavuori) and Team Applied Ballistics, explains how to determine wind direction and velocity using a variety of indicators. Praslick, now retired from the U.S. Army, was an 18-time National and 2-time World Champion coach with the USAMU.
Video ONE: Wind Theory Basics — Understanding “Wind Values”
In this video from UltimateReloader.com, Emil explains the basics of modern wind theory. To properly understand the effect of the wind you need to know both the velocity of the wind and its angle. The combination of those variables translates to the wind value. Emil also explains that the wind value may not be constant — it can cycle both in speed and velocity. Emil also explains some of the environmental conditions such as mirage that can reveal wind conditions.
Video TWO: Determining the Direction of the Wind
Key Point in Video — Find the Boil
Emil explains how to determine wind direction using optic. The method is to use spotting scope, riflescope, or binoculars to look for the “Boil” — the condition in mirage when the light waves rising straight up. The wind will generate that straight-up, vertical boil in your optics when it is blowing directly at you, or directly from your rear. To identify this, traverse your scope or optics until you see the boil running straight up. When you see that vertical boil, the direction your optic is pointing is aligned with the wind flow (either blowing towards you or from directly behind you).
Video THREE: The No Wind Zero Setting
In this second video, Emil defines the “No-Wind Zero”, and explains why competitive shooters must understand the no-wind zero and have their sights or optics set for a no-wind zero starting point before heading to a match. In order to hit your target, after determining wind speed and direction, says Emil, “you have to have your scope setting dialed to ‘no wind zero’ first.”
Coach of Champions — Emil Praslick III
SFC Emil Praslick III, (U.S. Army, retired) works with Berger Bullets and Applied Ballistics. Emil served as the Head Coach of the U.S. National Long Range Rifle Team and Head Coach of the USAMU for several years. Teams coached by Emil have won 33 Inter-Service Rifle Championships. On top of that, teams he coached set 18 National records and 2 World Records. Overall, in the role of coach, Praslick can be credited with the most team wins of any coach in U.S. Military history.
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At the request of our readers, we provide select “Deals of the Week”. Every Sunday afternoon or Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
NOTE: All listed products are for sale to persons 18 years of age or older. No products are intended for use by minors.
This week we mark a special milestone — our 400th BargainFinder Deals of the Week! That works out to 7.7 YEARS of bargains, promos, and discounts. To mark our 400th Week of Hot Deals, we are doubling the number of deals listed, for a total of TWENTY deals — all under $400.00.
The Frankford Arsenal Intellidropper powder scale/dispenser has earned positive owner reviews. This unit is FAST, and you can program your loads with a smart-phone App. Get it now for $179.49 on Amazon, a great deal.
Everyone needs a borescope to check barrel fouling. Teslong makes very good borescopes. Get the Basic Model for $55.99 or get the Rigid Model for $99.99 with a metal shaft. Both work well.
Berger bullets are hard to find but we found these 7mm 184gr Hybrid bullets in stock and ready to ship. Grab them now before someone else does.
Simple targets are hard to beat at the range. We love these Champion Sight-In Targets for only $3. Grab a bunch and go have some fun.
This is a great deal — Get a 9mm Smith & Wesson SD9VE pistol with built-in Crimson Trace Laser and extra night sights for just $389.99.
These 10-power Vortex Diamondback Binoculars are rubber-armored and 100% weatherproof with O-Ring seals. Get these for just $137.99, a 40% savings off the regular $229.99 price.
If you want to upgrade your AR15 rifle, consider grabbing a RISE AR-15 Trigger. This trigger has a clean break with a short reset and comes with anti-walk pins for installation.
With this Frankford Universal Seating Die you can load NINE different bullet diameters: .224, .243, .257, .264, .277, .284, .308, .325, .338. Now just $62.24 on Amazon this kit includes micrometer stem, 9 bullet alignment sleeves, 3 VLD bullet seating stems, and molded storage case.
This dual-mode rifle case for hunters and tactical shooters boasts comfortable shoulder straps, plus large external pockets. This case is offered in green or black in 28″, 36″, 42″, and 51″ sizes. The 36″ model starts at $65.25 on Amazon.
Seat primers easily and reliably with the RCBS hand primer tool. The tray holds 100 primers and allows good feel of seating depth. The universal mount fits all common rim sizes.
Do you shoot an M1 Garand or 1903 Springfield? Here’s a great deal on genuine mil-spec .30-06 SPRG ammo from the CMP. Get 400 rounds of 150gr .30-06 M2 Ball ammo for just $392.00. This comes in original ammo can with 20rd boxes.
Sometimes you just need a simple, inexpensive scope for your hunting rifle. The Simmons 2.5-10x40mm Aetec is great for the price and is even illuminated for those dusk and dawn shots.
Match target bullets are still hard to find but we saw these Hornady 6.5 A-Tips and the price is great. These are top level bullets so don’t hesitate to grab some for your next match.
Here’s an excellent package deal. Get a S&W 9mm M&P Shield M2.0 pistol plus range bag, cleaning kit, AND a nice folding knife — all for just $374.99 — a $53 savings.
Protect your ears while hearing those around you with these Walker Electronic Muffs. They feature comfortable cups and 27db NRR for your protection.
You have the equipment but do you have the skills to shoot in the wind? Grab The Wind Book and you’ll get tips and tricks from wind experts so you can dominate your next match.
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The 6.5 Creedmoor is now one of the most popular cartridges chambered in factory rifles. It found favor among hunters and PRS competitors, but then its little brother the 6mm Creedmoor became widely adopted because the 6mm version delivered less recoil, equivalent or better ballistics, and lower bullet cost.
There’s another Creedmoor cousin, the 22 Creedmoor, basically a 6mm Creedmoor necked down to .224 caliber. While this certainly can be used for PRS and tactical competition, the 22 Creedmoor seems to be ideally suited as a high velocity varmint round — something to replace the 22-250. You get 22-250 class velocities with a more modern cartridge design, and high-quality brass.
LEARN MORE about the 22 Creedmoor
There is an excellent write-up in the GunsAmerica Digest about the 22 Creedmoor cartridge. Reviewer Jeff Cramblit built a 22 Creedmoor rifle and tested it with a variety of bullet weights. He concluded it worked best as a varminter, but could also do PRS duty, provided it is loaded under the 3200 fps velocity limit common in PRS matches. CLICK HERE to read full GunsAmerica 22 Creedmoor test report.
Since there is not yet a SAAMI spec for the 22 Creedmoor, the cartridge is officially still a wildcat. However some ammo-makers have produced 22 Creedmoor loaded ammo: Copper Creek, Gunwerks, and Spark Munitions. Copper Creek has produced the most 22 Creedmoor loaded ammo varieties, with 18 different bullet options from 68 grains to 95 grains, including two lead-free bullet types. However, most everything is “out of stock” right now. Copper Creek also offers load development packs with either Peterson or Hornady brass. Here are five Cooper Creek options with Sierra and Berger bullets:
In addition, multiple companies have offered 22 Creedmoor cartridge brass: Alpha Munitions, Atlas ADG, Hornady, and Peterson Cartridge. The Peterson 22 Creedmoor brass is excellent.
Of course you can neck down high-quality Lapua 6mm Creedmoor brass. Lapua brass has outstanding consistency and durability. Choose from large primer or small primer types. Necking down is a relatively easy one-step operation with a neck-sizing or full-length sizing die. You’re just stepping down to .224 from .243 — not that big of a jump.
22 Creedmoor Brass from Peterson Cartridge
According to Derek Peterson, President of Peterson Cartridge, “We decided to build the tooling to make our .22 Creedmoor brass in response to the uptick in long-distance predator and varmint hunting. Plus the round is just straight-up fun to shoot. It is a low-recoil, flat shooting, wind-bucking round [that is] deadly accurate up to 800 yards.”
“When we designed the tooling for the .22 Creedmoor we set out to make casings with improved features”, Peterson added. “And we were successful. We increased the head hardness to tolerate higher pressures. And we increased our internal volume slightly to work better with the slow-burning powders [such as Reloder 26 or H1000].”
22 Creedmoor for Varmints — Video from the Varmint Fields of Eastern Oregon
Bullet Choices for 22 Creedmoor
If you have an appropriate twist-rate barrel, you can load the 22 Creedmoor with heavy 85-95 grain bullets. However, we think that, for varminting, the cartridge is better suited for lighter 65-80 grain bullets. This yields high velocities that provide explosive impacts on small varmints.
This GunsAmerica photo shows, L to R, 90gr Sierra MK, Hornady 88gr, 80gr, and 75gr .224 caliber bullets.
What is the Best Role for the 22 Creedmoor?
GunsAmerica tester Jeff Cramblit favors the 22 Creedmoor as a varmint round: “The performance of the 22 Creedmoor with 75-80 grain bullets makes it an outstanding varmint cartridge. I’ve seen claims of 80 grain Bergers at 3500 fps out of 26″ barrels, which would be devastating on any varmint. Loaded ammunition is available with bullets in the 70-75 range leaving 24” barrels at velocities around 3400+ fps, a bit more conservative than personal hand-loading, but still making it a very flat shooting, low recoiling round delivering impressive results.”
Jeff says the 22 Creedmoor will also work for PRS with heavier bullets: “I built the 22 CM to be a dual-purpose gun, or actually a 3-purpose gun. The first was for the coyotes and varmints previously mentioned. The second was for shooting PRS (Precision Rifle Series) style matches on occasion, and the third was for hunting deer-sized game. As with any multi-purpose tool there tends to be compromises.”
22 Creedmoor Cartridge Dimensions (No SAAMI Spec Yet)
More Efficient Alternatives — the 22 BR and 22 BRA
If you already have a 6mmBR rifle, and you want a higher velocity cartridge for varmint shooting, you may want to consider just necking down your brass. We’ve shot the 22 BR in the varmint fields and a steel match. This cartridge offers excellent accuracy, and is very flat shooting. We recommend getting a fairly fast-twist barrel so you can shoot the longer, high-BC bullets if you want to use your 22 BR in local matches. You’ll find that shorter 40gr to 66gr varmint bullets shoot great even in the faster-twist barrels.
For more information on the 22 BR for varminting and target shooting, with recommended loads for 40gr to 90gr bullets, read our Accurate Shooter 22 BR Cartridge Guide.
If you want more velocity than a 22 BR offers, you can have your barrel chambered for the 22 BRA (BR Ackley). With its 40-degree shoulder, the 22 BRA offers a few more grains capacity, so you can get more FPS with all classes of bullets. Fire-forming is easy — just use a normal 22 BR load with good bullets and shoot. We’ve fire-formed a 22 BRA in a varmint match and it showed excellent accuracy — there’s no need to waste bullets fire-forming. Go ahead and fire-form during a fun match.
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Is factory 6.5 Creedmoor ammunition good enough to win a PRS or NRL competition? The answer is a resounding “YES” if we’re talking about Berger ammunition. Produced with Berger match bullets and premium Lapua brass, this Berger 6.5 Creedmoor ammunition demonstrated excellent accuracy, impressive velocity, and very good ES/SD numbers. When tested at 1000 yards with an MPA-stocked PRS rig with Rem 700 action, this ammo showed just half-MOA of vertical, and produced a group that would have been a 50-1X in F-Class competition. That’s quite impressive for a PRS rig.
This ammo test was performed by our friend Erik Cortina from Texas. The reigning SW Nationals F-Open champion, Erik is a top F-Class competitor who also shoots tactical matches (for fun and glory). A couple seasons back, Erik built a new 6.5 Creedmoor with a Remington 700 action. Though this rifle sports a top-shelf MPA chassis and premium Kahles scope, Erik calls this his “budget build” because it has a plain Rem 700 factory action rather than the elite Borden actions he normally runs. Erik’s actions of choice are the Borden Mountaineer for PRS and Borden BRM-XD for F-Class.
Erik posted: “Shot my budget 6.5 Creedmoor … with Berger Bullets factory ammo. I shot five rounds over the chrono to get speed. I used BC info from the box and it all lined up properly. I adjusted my ECTuner to tune load and it took just 15 shots to get it shooting well. It’s simple with good components.”
This Berger factory ammo features Berger 130gr Hybrid OTM Tactical bullets. The Lapua 6.5 Creedmoor cases have a large rifle primer. You can see this ammo displays good velocity with Extreme Spread and Standard Deviation rivaling good hand-loads.
Cortina says the very accurate Brux barrel and razor-sharp 6-24x56mm Kahles scope help achieve this kind of outstanding performance at 1000 yards. Here are the key components for Erik’s latest PRS rig:
Barrel Tuner by Erik Cortina — Fits Behind Muzzle Brake
This rifle features a barrel tuner designed and crafted by Erik Cortina. You can the EC Barrel Tuner alone, or, as you can see, the EC Tuner can be fitted BEHIND a muzzle brake. Erik tells us: “The EC Tuner allowed me to tune the barrel to my ammo rather than tuning the ammo for barrel as is done when reloading. With the tuner, there is no need to try different brands of ammo as they can all be tuned to shoot as good as possible in my rifle.”
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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.
Here’s a cool video showing how bullet, brass, and ammunition are produced at the 
John Masek Wins His First Nationals
If you wonder how ammo is made, starting with raw metal, check out this video from 
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.
Drag Models — G7 is better than G1 for Long-Range Bullets
If you already have a 6mmBR rifle, and you want a higher velocity cartridge for varmint shooting, you may want to consider just necking down your brass. We’ve shot the 22 BR in the varmint fields and a steel match. This cartridge offers excellent accuracy, and is very flat shooting. We recommend getting a fairly fast-twist barrel so you can shoot the longer, high-BC bullets if you want to use your 22 BR in local matches. You’ll find that shorter 40gr to 66gr varmint bullets shoot great even in the faster-twist barrels.
Cortina says the very accurate Brux barrel and razor-sharp 6-24x56mm Kahles scope help achieve this kind of outstanding performance at 1000 yards. Here are the key components for Erik’s latest PRS rig:
