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November 5th, 2025

Small-Bore Rifles Book — Excellent Resource for Rimfire Shooters

If you are shopping for a new rimfire rifle, particularly a .22 LR, you may want to pick up a copy of Small-Bore Rifles: A Guide for Rimfire Users by C. Rodney James. This provides a detailed history of rimfire cartridges and provides a look at a variety of rimfire rifles for various applications — target, plinking, varminting. SSUSA.org explains this book covers “every aspect of rimfire shooting, from a detailed history of its calibers and platforms, to a discussion of proper maintenance and expected accuracy[.]” American Rifleman Editor-in-Chief, Mark Keefe, writes: “This little book is the most useful treatment of the [.22 Long Rifle] I have read, and it is highly recommended for anyone serious about being a rimfire rifleman.”

The 248-page book is available for $17.99 from Skyhorse Publishing in both paperback and ebook formats. You can view a 40-page sample of this book, including the index, on Amazon. CLICK HERE, then, when the page opens on Amazon.com, click the “READ SAMPLE” link below the book cover image. Amazon offers the book in Kindle format for $12.99.

This book focuses primarily on the .22 LR (Long Rifle) cartridge. However, it does include extensive information on other rimfire chamberings, including .17 PMC/Aguila, .17 HMR, and .22 WMR. Here’s part of the 22 WMR section:

Here are reviews by recent verified purchases of the book:

“Everything you could ever want to know about the development of the .22 round, the ballistics of the same and the history of early bolt-action .22 rifles are presented in an easy-read style by a very knowledgeable author. There are plenty of color photographs and a lot of useful maintenance information throughout the book. I do have one complaint… the book has almost no information on semi-automatics.” — K. Greene

“A must-read book for the rimfire enthusiast. Much accurate information presented in an enjoyable format. From the earliest rimfire rounds to the latest 17s [are] all are covered in this book. Bolt actions, semi-autos and single-shot rifles are covered with the pros and cons of each. What makes for accuracy from the rifle to the cartridge is well covered.” — Ken Cook

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November 5th, 2025

Sectional Density of Bullets — What You Need to Know

Bullet projectile sectional density formula Sierra Bullets

by Sierra Bullets Ballistic Technician Paul Box
All of us who have been in reloading and shooting for any period of time have read how sectional density has been regarded as a bullet’s ability to penetrate. Back before high velocity came along and modern bullet design, the easiest way to get more “power” and penetration was by increasing the diameter and mass. After all, a bowling ball will hurt more than a golf ball, right?

Let’s take a closer look at sectional density.

The formula for calculating sectional density is pretty simple and straight forward. Take the bullet weight and divide by 7000. This number is then divided by the bullet diameter squared Two bullets of equal weight and the same diameter will have equal sectional sectional density. No regard is given to the bullet construction. This is where the fly hits the soup in considering sectional density as far as penetration is concerned.

Section Density Formula: (Bullet Weight divided by 7000) divided by Bullet Diameter squared.

Bullet construction is the biggest factor in how it is able to penetrate. The best example I can think of here is to look at the Sierra .224 55 Gr. FMJBT GameKing #1355 compared to the 55 Gr. BlitzKing #1455. Both are .224 and weigh 55 grs. Both have a sectional density of .157. But there is a huge difference in their construction. The FMJ has a thick jacket and is designed to penetrate. The BlitzKing is designed for fast and rapid expansion with little concern for how deep they will penetrate.

The next time you’re choosing a bullet, look at the construction and less at the sectional density number. It’s all about the construction anyway. If you have any questions or would like to discuss sectional density or bullet penetration further, please give us a call at 800-223-8799 or shoot us an email at sierra@sierrabullets.com.

Sierra Bullets reloading tips

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November 4th, 2025

Replace Your Gun Safe Keypad Batteries — Don’t Get Locked Out

If the battery on your safe’s electronic lock is
more than a year old, or if it is not giving you the
right voltage, replace it today!

safe battery gunsafe sargent greenleaf

Gunsafe safe keypad control battery batteriesThis time of year, many readers are putting their guns away in a safe for the winter. It’s easy to just tuck the guns away and forget about them. But there’s something you should do before you shut the safe door.

If you have a safe with an electronic keypad, you should replace the battery every year as a precautionary measure. Trust us, you don’t want to come back in a few months and find that the keypad memory is kaput, and you’re locked out. That can lead to an expensive locksmith visit.

NOTE: Some lock systems use more power and you may need to change your batteries TWICE a year. Batteries aren’t that expensive — you may want to replace batteries TWICE a year if you open and close your safes very frequently.

Low Voltage Battery? You May Be Locked Out…
Here’s a true story. I have one safe with a Sargent & Greenleaf (S&G) keypad. A couple years back, in early December, I went to get into the safe. I punched in the correct combination, but all I got was a rapid “beep, beep, beep, beep” after I finished the last combination entry. I tried again to ensure I entered the combination correctly (I did). But again, the locking system responded with multiple rapid beeps indicating something was wrong. And the safe would not open. Now I was worried….

I popped out the battery holder (which slides in from the bottom of the keypad housing on the door). I removed the battery and tested it with a volt-meter. The 12-month-old Duracell 9-volt battery only registered 6.1 volts.

Low voltage was the problem. I went down to the store and got a couple new 9V batteries. I tested the new batteries and both measured 9.4 volts output. I slipped one of the new 9V batteries into the keypad housing, punched in the combination and everything worked OK again. Eureka.

Most electronic locks for safes WILL “remember” the combination for a period of time even when the battery is low (and the keypad’s “brain” should retain the combination when you remove the battery for replacement). However, a dead battery, or extended periods of low voltage can give you problems. Don’t rely on wishful thinking…

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November 3rd, 2025

Quickly Determine Your Dominant Eye with This Simple Test

6.5 Creedmoor Annealing

Shooting Sports USA Eye dominanceDo you know which one of your eyes is dominant? It’s easy to determine eye dominance with a simple exercise. Pick an object about 6-10 feet away (a light switch or door knob works well). Make an “OK” sign with your right hand (see photo) and hold that about 18″ from your face. Now, with both eyes open, look through the circle formed by your thumb and index finger. Center the circle on the object, so you can see the object in the middle.

Now, here’s the important part — while still holding your hand up, centered on the object, first close your right eye. If you don’t see the object anymore, then your right eye is dominant. If you still see the object, then repeat the procedure with the left eye shut and right eye open. If you don’t see the object when your left eye (only) is closed, then you are left-eye dominant.

6.5 Creedmoor AnnealingThe digital archives of Shooting Sports USA contain many interesting articles. A while back, Shooting Sports USA featured a “must-read” expert Symposium on Eye Dominance, as it affects both rifle and pistol shooting. No matter whether you have normal dominance (i.e. your dominant eye is on the same side as your dominant hand), or if you have cross-dominance, you’ll benefit by reading this excellent article. The physiology and science of eye dominance is explained by Dr. Norman Wong, a noted optometrist. In addition, expert advice is provided by champion shooters such as David Tubb, Lones Wigger, Dennis DeMille, Julie Golob, Jessie Harrison, and Phil Hemphill. NOTE: If the story doesn’t open at the links, go to the ssusa.org home page first, indicate you are over 18, and then CLICK HERE.

Top Rifle Champions Talk About Eye Dominance:

David Tubb — 11-Time National High Power Champion
I keep both eyes open, always. Some use an opaque blinder in rifle or shotgun shooting. If you close your non-dominant eye, you will not get as good a sight picture. If your aiming eye is not your dominant eye, you have even more of a problem to overcome.

Lones Wigger — World, National and Olympic Champion Rifleman
Shooters should try to use the dominant eye unless the vision is impaired and the non-dominant eye has better vision. You should always shoot with both eyes open since this will allow the shooting eye to function properly.

Dennis DeMille — National Service Rifle Champion
I close my non-shooting eye initially. Once I pick up my sight picture, it’s not something I focus on. For those that use a patch, I recommend that they use something white to block their view, rather than cover the eye.

Bruce Piatt — 2025 World Action Pistol Team Championship — Member of Winning Team CMP-USA
Some shooters, especially those with nearly equal or cross-dominance, will naturally find themselves squinting one eye. When anyone does this, you are also closing your dominant eye to some extent and adding stress to your face.

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November 2nd, 2025

Linear Compensators — Function Compared to Muzzle Brakes

Brownells Linear compensator video

In this interesting video, Brownells Gun Tech Caleb Savant covers the topic of linear compensators, aka “blast diffusers” or “linear blast devices”. These are quite different in function from a typical muzzle brake and they are NOT a sound suppressor. Unlike a traditional muzzle brake, a linear compensator directs the muzzle blast forward, AWAY from the shooter. This is not only good for the shooter but also for folks next to the shooter, either at the range or in a CQB law enforcement or military situation.

A “Linear Compensator”, also known as “blast diffuser”, my look similar to a muzzle brake. But it works differently. A typical muzzle brake shoots blast out the side, and can be pretty annoying for someone positioned next to the shooter. By contract, the Linear Compensator direct blast force more forward. This helps reduce perceived recoil, and importantly doesn’t send hot gasses left and ring to nearby shooters or observes. Muzzle brake output can be very annoying. This Editor once was shooting next to a .338 Lapua Magnum with a brake, just a couple feet away. With each .338 LM shot I could feel heat on arms/hands and actually feel the bones in my forearm vibrate.

Attachment Methods — Direct Thread Mounting vs. Quick-Attach Mounting
Linear compensators have become much more popular in recent years as AR-15 pistols and SBRs have proliferated. Some linear comps, such as popular models from Midwest Industries and the Troy Claymore, attach directly to the muzzle, just like a traditional flash hider or muzzle brake.

Other Linear Compensators are slip-on, quick-attach components that mount OVER another muzzle device. For example, the VG6 Precision CAGE Device (Concussion Altering Gas Expansion) attaches directly over one of their standard muzzle devices. Almost every company that makes a sound suppressor also offers a linear compensator, which typically attaches to the muzzle the same way as the silencer.

Video find by Boyd Allen. We welcome reader submissions.
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November 2nd, 2025

Excellent Ballistics App for iPhones & iPads — FREE to Download

Ballistic AE Mobile App Ballistics Program solver JBM iphone, iPod, iPad

Ballistic AE Mobile App Ballistics Program solver JBM iphone, iPod, iPadNeed a top-notch Ballistics App for your iPhone or iPad? Start with Ballistic: Advanced Edition (AE), the number 1 (i.e. most installed) App for iOS systems (iPhones and iPads). Ballistics AE (Advanced Edition) is the most popular iOS ballistics program for many good reasons. It offers a full feature set with Ballistic Solver, Ballistic Comparison (with up to 8 projectiles), Target Log (records group sizes), Advanced WindKit, and more. The Ballistic: Advanced Edition software is easy to use, with nice controls. Underneath it all is the proven JBM Ballistics calculator. And here’s the kicker — this excellent mobile App software is now FREE to download and install on iPhones and iPads!

This Video Explains How to Set Up and Use Ballistic: Advanced Edition

Full-featured and easy to use, Ballistics AE has been refined over many years, and it supplies rock-solid solutions derived from JBM Ballistics solver (created by James B. Millard). Unlike some other Apps, Ballistics AE is STABLE on iPhones (with various OS levels). What’s cool is that Ballistics AE is now available for FREE for both iPhones and iPads. This software is now provided by Federal Premium Ammunition, with in-App purchase functionality.

Ballistic AE Mobile App Ballistics Program solver JBM iphone, iPod, iPad

We’ve used the Ballistic: Advanced Edition program on an iPhone 5S, iPhone 6, and iPad, and it performed well. Here are some of the features we liked:

  • 1. Mirrors output from online version of JBM Ballistics we often use for initial calculations.
  • 2. Controls are simple to use and (mostly) intuitive.
  • 3. Handy comparison feature lets you compare ballistics for different projectiles side by side.
  • 4. Advanced Wind Kit allows you to account for complex wind situations.
  • 5. Projectile and BC Databases are very comprehensive.
  • 6. Software is regularly updated to match Apple OS changes.

Ballistic-AE App for iPhone | Ballistic-AE App for iPad

Ballistic AE Mobile App Ballistics Program solver JBM iphone, iPod, iPad

This article is Copyright 2025 AccurateShooter.com. No republication is authorized. Any appearance of this story on another site obliges that site to pay liquidated damages and/or licensing fees.

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November 1st, 2025

Saturday Movies: Single-Stage Reloading Press Showcase

RCBS Rock Chucker MEC Marksman Lyman Brass smith ideal Frankford co-ax forster Hornady iron Lee Classic Cast Breech Lock Press

Hand-loaders have never had so many great choices in single-stage presses, with many different configurations and features. There are classic O-Frame presses, Coax-style presses, Open-front presses, Pyramid presses, and compact C-Frame presses. Here is our 2019 Single Stage Press Showcase with products from Forster, Hornady, Lee, Lyman, MEC, and RCBS. We’ve included short videos showing the features of these reloading presses.

If you are shopping for a new press you should look at the various features of each. You may prefer something classic like a Rock Chucker, or the innovative open-front MEC. If you are looking for a compact press to use at the range, the Lyman C-Frame is very impressive for the price. And the Forster Co-Ax remains a great addition to any loading room.

MEC Marksman Single-Stage Press

If you are looking for a new, full-size single-stage reloading press, definitely consider the MEC Marksman. Created by the makers of the popular MEC shotshell reloading systems, the MEC Marksman combines a sturdy cast-iron frame with a modern open-front design. If you are looking for a new, full-size single-stage reloading press, definitely consider the MEC Marksman. Created by the makers of the popular MEC shotshell reloading systems, the MEC Marksman combines a sturdy cast-iron frame with a modern open-front design. With a $245.49 street price, the MEC Marksman press now costs more than an RCBS Rock Chucker Supreme press, but the MEC offers some distinct advantages — such as an open front plus a floating shell-holder system.

MEC Marksman Press Gavin Gear single stage open front press die caddy accessories

Our friend Gavin Gear of UltimateReloader.com got his hands on a MEC Marksman press and put it through its paces. He came away impressed with the product, saying it delivers excellent performance, and has many impressive features. Gavin tells us: “Cast iron tools and machines are a lifetime investment. The made-in-USA MEC Marksman features ductile cast-iron construction, an open-front frame design for easy cartridge access, a new floating shell-holder design with a unique retention system, and ambidextrous handle setup.” MEC also offers a wide selection of accessories for the Marksman press, including a press riser/mount, shell-holder caddy, and die trays.

Forster Co-Ax Press

co-ax forster Hornady reloading single-stage PressIf you are not yet familiar with the many unique features of the Forster Co-Ax, we recommend you watch the video above, a very thorough video review by Rex Roach. This shows how the press operates and highlights the design elements which set the Co-Ax apart from every other reloading press on the market. This 14-minute video shows the key Co-Ax features, explaining how the floating case-holder jaws work (3:30 time-mark), how the dies are held in place (4:40 time-mark), how spent primers are captured (6:10 time-mark), and how to set the primer seating depth (10:00 time-mark). We’ve used a Co-Ax for years and we still learned a few new things by watching this detailed video. If you are considering purchasing a Co-Ax, definitely watch this video start to finish.

In recent years, Forster Co-Ax® presses have been somewhat hard to find, as demand has out-stripped supply. The Co-Ax has many dedicated fans, given its unique features, such as the floating case-holder jaws, and easy, rapid slide-in/slide-out die placement. We’ve also found that Co-Ax presses load very straight ammo and we like the ability to switch between short handle (good for bullet seating) and long handle (ideal for heavy case-sizing tasks). We also think the Forster Co-Ax has one of the best spent primer capture systems on the market — a straight drop into a removable plastic cup. Simple and it works.

Lyman Brass Smith Victory Single-Stage Press

Lyman Brass Smith Victory Single stage press videoLyman’s sturdy Victory Single-stage Press is a full-size unit that competes with the RCBS Rock Chucker Press. With beefy cast iron construction, the Victory’s strength and leverage rivals the Rock Chucker. The press operates smoothly and the handle can be mounted on either side.

If you like to prime cases using a press, this Victory press has a priming system that’s much easier to use than the RCBS Rock Chucker system. The priming tube is right up front, with multiple primers loaded vertically in a tube. Simply push the shuttle at the button of the tube to advance the primer into place.

For convenience, the entire primer-loading system can also be removed so it doesn’t interfere with case and bullet-handling operations. We generally prefer to prime cases separately using a dedicated hand- or bench-mounted tool, but the Victory press does the job nicely.

Overall, the Victory is a great value in a full-size “O-Frame” press with sturdy construction and a solid Lyman warranty. It is available now for $219.99 on Amazon.

RCBS Rock Chucker Supreme Single-Stage Press

RCBS Rockchucker Rock Chucker Supreme Single Stage reloading press Bruno ShootersNearly every serious hand-loader has owned or used the RCBS Rock Chucker press. This Editor still uses a Rock Chucker passed down by his brother 20 years ago. And yes, it is still going strong. The latest Rock Chucker Supreme single-stage press features an improved “upside-down Y-path” dual-bin spent primer catcher. Otherwise the Rock Chucker Supreme remains big, strong, versatile and sturdy. It has very strong linkages, with a compound leverage system providing plenty of power — FL-sizing is a breeze even with large, magnum cases. The 1″-diameter ram has 12.5 sq. inches of ram-bearing surface.

The Rock Chucker offers a secondary 1 1/4″ x 12 thread for shotshell reloading dies and Piggyback 3 upgrade. The Rock Chucker Supreme retails for $234.99 now at Midsouth. The Rock Chucker Supreme combines easy operation, ambidextrous handle, and outstanding strength. It has a big 4.25″ loading window that works even for big magnum cases. The long handle and central pivot design provide outstanding leverage. The RCBS Rock Chucker is definitely a quality product that can last a lifetime. For heavy-duty sizing chores this remains one of the best choices in single-stage presses.

Lyman Brass Smith Ideal C-Frame Compact Press

The Lyman Brass Smith Ideal Press is a very affordable, cast iron C-Frame reloading press. We think it is the new “class leader” in compact presses. This works great as a secondary press for your reloading room or a small press you can take to the range. The large front opening allows you to access the shell holder without hitting the support bar on other types of presses. Unlike other compact presses made from aluminum, Lyman’s Ideal press is cast iron so it is rigid and strong. The high-quality steel ram is one inch in diameter. The Brass Smith is a true ambidextrous press that can be accessed from either side and mounted the same. This is a great choice for a second, auxiliary press for depriming and bullet seating. It is now just $134.99 at MidwayUSA.

Lyman Ideal C frame iron press midsouth shooters

Hornady Iron Single Stage (Open-front) Press

In this “Reloading with Rosie” video, the attractive female host loads some ammo using the Hornady Iron Press. With a beefy, pyramid-style cast-iron frame with an open front, this press offers some advantages over a traditional “O-Frame” type press. Access is considerably easier, for one thing. And the top of the press includes slots to hold dies and tools — that’s really a very nice feature that saves time. Also an optional “automatic” priming system shuttles primers from a vertical tube in the back to the shell-holder in the front. That’s clever. Over all the Iron Press is a nice piece of engineering — good job Hornady. It is offered for $289.99 at Midsouth.

Hornady Iron Press video

Lee Classic Cast (Iron) Breech Lock Press

Lee Classic Cast Breech Lock PressThe Lee Classic Cast Breech Lock Press offers excellent value for the money ($190.99 at Midsouth). Based on the proven design of the Classic Cast press, the updated Breech Lock series adds the quick-change die bushing and an improved primer drop system. This press is strong, with cast iron frame, all-steel linkage, and 12 square inches of ram bearing surface.

Lee says this press has the “largest opening and the longest stroke in the industry” among O-frame type presses. The handle can be mounted on either side. We love the fact that the handle ANGLE can be adjusted, as well as the lever arm length — that allows you to adjust travel and leverage to suit your preference. Smart engineering.

The new spent primer drop features a large-diameter hollow ram with clear hose that drops primers straight to a bin — that’s simple and effective. The press is very rigid and the base is wide enough for good stability. We have one of these Classic Cast Breech Lock Presses in our reloading room and it works well.

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November 1st, 2025

Bloody Nightmare — Pistol Powder Loaded in 7mm-08 Rifle Ammo

Varget Kaboom TiteGroup Hand injury reloading fingers accident

This is a grim tale. A man almost lost the use of his right hand, and did suffer terrible injuries to his fingers. All because he picked the wrong bottle of powder off the shelf. We have run this story before, and we will continue to run it every year, as a caution to our readers. This mistake is easy to make, but the consequences can be dire. Always, always double-check your powder labels before you start the hand-loading process. If you don’t, you may not have a hand to load with next time…

Similar Labels, Disasterous Consequences
The shooter, Denny K., was assembling some rounds for his brand new 7mm-08 Savage hunting rifle. He thought he was loading with Hodgdon Varget. Instead he had filled his powder measure with Hodgdon TiteGroup, a fast-burning pistol powder. The labels are similar, so the mistake is understandable. But the results were devastating. Here’s what 41 grains of TiteGroup can do in a 7mm-08:

Varget Kaboom TiteGroup Hand injury reloading fingers accident

Posting on the Firing Line, in a thread entitled “Lucky to Be Alive”, Denny writes:

“This is the hardest post to post. I know if I had read it a week ago my comment would have been: ‘You have no business reloading’. I had everything perfect, except pouring the wrong powder in the powder measure. I type this slowly with my left hand, embarrassed but … possibly saving someone else a tragedy or, like me, a long drive to the Emergency Room and surgery to save my finger.”

CLICK HERE for bigger, more graphic photo of injury.
Varget Kaboom TiteGroup Hand injury reloading fingers accident

The Still-Sealed Bottle of Varget
Denny did not initially comprehend exactly why the kaboom happened. He thought maybe his new Savage rifle was at fault. Then, on his return home, he discovered something…

Denny wrote: “The seven-hour period it took to go to ER, transport to Trauma Center and surgery made me think it was a Savage rifle issue. Brand new rifle, new brass, triple-checked loading data. The next day I was humbled when I realized the Varget powder was still sealed.

I knew what powder to use. I thought [Varget] was what I used. Not until the following day did I realize the Varget was still sealed.”

At that point, Denny realized what caused the accident — “operator error”. He knew he had to warn others about using the wrong powder: “I knew I needed to share my mistake, even though it is embarrassing, just to remind people. I’ve been reloading for 30 years…”

Editor’s Comment: Denny was not a novice reloader. His experience demonstrates that this kind of mistake can be made by any hand-loader, even one with decades of experience. Be safe guys, take your time when you load your ammo. Remove powders from measures after your loading sessions (pistol powders can look very similar to rifle powders). And by all means CHECK the LABEL on the jug. As the TiteGroup label says: “A little goes a long way.”

It’s not a bad idea to separate your pistol powders from your rifle powders, or perhaps even load for pistol in a separate part of your workshop.

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October 30th, 2025

Bullet Concentricity and Alignment — What You Need to Know

Sinclair concentricity 101 eccentricity run-out reloading plans

Sinclair International reloading toolsSinclair International has released an interesting article about Case Concentricity* and bullet “run-out”. This instructional article by Bob Kohl explains the reasons brass can exhibit poor concentricity, and why high bullet run-out can be detrimental to accuracy.

Concentricity, Bullet Alignment, and Accuracy by Bob Kohl
The purpose of loading your own ammo is to minimize all the variables that can affect accuracy and can be controlled with proper and conscientious handloading. Concentricity and bullet run-out are important when you’re loading for accuracy. Ideally, it’s important to strive to make each round the same as the one before it and the one after it. It’s a simple issue of uniformity.

The reason shooters work with tools and gauges to measure and control concentricity is simple: to make sure the bullet starts down the bore consistently in line with the bore. If the case isn’t properly concentric and the bullet isn’t properly aligned down the center of the bore, the bullet will enter the rifling inconsistently. While the bore might force the bullet to align itself with the bore (but normally it doesn’t), the bullet may be damaged or overstressed in the process – if it even it corrects itself in transit. These are issues we strive to remedy by handloading, to maintain the best standard possible for accurate ammunition.

The term “concentricity” is derived from “concentric circle”. In simple terms it’s the issue of having the outside of the cartridge in a concentric circle around the center. That goes from case head and center of the flash hole, to the tip of the bullet.

Factors Affecting Concentricity

The point of using this term is to identify a series of issues that affect accurate ammunition. Ideally this would work best with a straight-walled case; but since most rifle cartridge cases are tapered, it equates to the smallest cross section that can be measured point by point to verify the concentric circle around the center. For the examples below, I’m working with .308 Winchester ammo.

Concentricity run-out cartridge case
Figure 1: The cartridge.

Concentricity run-out cartridge case
Figure 2: Centerline axis of the case, extending from flash hole to case mouth.

The case walls have to be in perfect alignment with the center, or axis, of that case, even if it’s measured at a thousandth of an inch per segment (in a tapered case).

Concentricity run-out cartridge case
Figure 3: Case body in alignment with its axis, or centerline, even in a tapered case.

The case neck must also be in alignment with its axis. By not doing so you can have erratic bullet entry into the bore. The case neck wall itself should be as uniform as possible in alignment and in thickness (see the M80 7.62x51mm NATO cartridge in Figure 5) and brass can change its alignment and shape. It’s why we expand the case neck or while some folks ream the inside of the neck and then turn the outside for consistent thickness, which affects the tension on the bullet when seated.

Concentricity run-out cartridge case
Figure 4: Neck in alignment with center of the case axis.

Concentricity run-out cartridge case
Figure 5: Variations in case neck wall thickness, especially on some military brass, can cause an offset of the bullet in its alignment. This is an M80 ball round. Note the distinct difference of the neck walls.

Having a ball micrometer on hand helps, especially with military brass like 7.62x51mm in a semi-auto rifle, where there are limits as to how thin you want the neck walls to be. In the case of 7.62 ball brass you want to keep the wall to .0145″.

Concentricity run-out cartridge case
Figure 6: A ball micrometer like this RCBS tool (#100-010-268) can measure case neck thickness.

Turning the outside of the neck wall is important with .308 military cases regardless of whether you expand or ream the neck walls. There are several outside neck turning tools from Forster, Hornady, Sinclair, and others. I’ve been using classic Forster case trimming (#100-203-301) and neck turning (#749-012-890) tools for 40 years.

Bullet Run-Out
The cartridge, after being loaded, still needs to be in alignment with the center of the case axis. Figure 7 shows a bad example of this, a round of M80 ball. A tilted bullet is measured for what’s known as bullet “run-out”.

Concentricity run-out cartridge case
Figure 7: An M80 round with the bullet tilted and not aligned with the axis. This will be a flyer!

Run-out can be affected by several things: (1) improperly indexing your case while sizing, which includes not using the proper shell holder, especially while using a normal expander ball on the sizing die (it also can stretch the brass). (2) The head of a turret press can flex; and (3) improper or sloppy bullet seating. This is also relevant when it comes to using a progressive press when trying to load accuracy ammo.

Mid Tompkins came up with a simple solution for better bullet seating years ago. Seat your bullet half way into the case, back off the seater die and rotate the case 180 degrees before you finish seating the bullet. It cuts down on run-out problems, especially with military brass. You also want to gently ream the inside of the neck mouth to keep from having any brass mar the surface of the bullet jacket and make proper seating easier. A tilted bullet often means a flyer.

Concentricity run-out cartridge case
Figure 8: Proper alignment from the center of the case head to the tip of the bullet.

» CLICK HERE to READ FULL ARTICLE With More Photos and Tips

(NOTE: This links to a Web Archive version of the original Sinclair Int’l article.)


*Actually some folks would say that if we are talking about things being off-center or out-of-round, we are actually talking about “eccentricity”. But the tools we use are called “Concentricity Gauges” and Concentricity is the term most commonly used when discussing this subject.

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October 29th, 2025

Save Barrel Life, Bullet Cost, and Time — Fire-Form with Foulers

Fire-forming fouler barrel life fouling shots

PPC Fire-formingFire-Form with Foulers
Here’s a tip for guys who shoot the 6 PPC, 6 Dasher, 6 BRA, .284 Shehane, or other wildcat cartridges that require fire-forming. Use your fouler shots to fire-form new cases. That way your fouler shots do “double-duty” and you get your brass fire-formed without putting extra rounds through your expensive barrel.

This procedure is recommended by Joel Kendrick, the 2004 IBS 600-yard Shooter of the Year. After he cleans his barrel, Joel knows it takes two or three shots to foul in the bore before accuracy returns. (YMMV — some barrels may need five or six foulers.) When shooting his PPC, Joel uses those fouler shots to fire-form his new brass. Joel explains: “I like to have relatively new brass always ready. By fire-forming a couple cases after each barrel-cleaning during a match, by the end of the weekend I’ve got a dozen or more freshly fire-formed cases to put into the rotation. If you do this with your fouler shots you get your fire-forming accomplished without using up any extra barrel life.”

This not only saves barrel wear, but it saves you trips to the range for the purpose of fire-forming. We thank Joel for this smart suggestion. For those who do not have a dedicated barrel for fire-forming, this should help keep your round-count down. Note: With this fouler fire-forming routine, you should ALWAYS do the fire-forming with the SAME POWDER you load for your match ammo. Joel currently works as the Supplier Quality Process Engineer for Parker TruTec — MMI Inc., a company that offers barrel surface coatings that can further extend your barrel life.

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