When you make a reloading mistake, you may need to “pull down” assembled ammo. The embedded UltimateReloader.com video demonstrates how to use the Hornady Cam-Lock bullet pulling system.
When Reloading Goes Bad — The Danger of Over-Charging
Our friend Gavin Gear of UltimateReloader.com was recently reloading some 9mm pistol ammo with his Hornady progressive press. As part of his reloading procedure, he visually checks the cases — and he noticed that the charges seemed high. Sure enough, his most recently-produced rounds were about two grains over spec. He diagnosed the issue: “I was using a powder measure without a baffle. What happened was, over the course of the loading session, things settled in, and the charge level increased.”
Not knowing just when his powder measure started delivering too much powder, Gavin decided, for safety’s sake, to pull down all the ammo he had just reloaded. Yes that’s time-consuming, but it’s better than the alternative — having a dangerous Kaboom while shooting. With fast-burning pistol powders, a two-grain over-charge could cause a blown case, damaged firearm, and/or serious injury.
Watch Cam-Lock Bullet Puller Used to Remove Bullets from Loaded Ammo:
Use of Bullet Puller starts 4:00 minutes into video.
Gavin says it is vitally important to perform safety checks during the reloading process: “You’ve got to do it — check every single round to make sure there IS powder, and that there’s not too MUCH powder. Double, Triple, Quadruple check your components… and your powder charges. You can’t be too careful.”
To pull down a loaded round, first place the cartridge in the shellholder on your press ram. Then raise the round up into the bullet puller device installed where a die would go. The Hornady Cam-lock bullet puller works by clamping the bullet in a collet when you flip down the red-coated lever. Then, with the case held by the rim in the shell-holder, the bullet exits the cartridge as the press ram is lowered. It takes time, but it’s pretty fool-proof once you get the hang of it. This entire process is illustrated in Gavin’s video, starting near the four-minute mark.
The Hornady Cam Lock Bullet Puller has four (4) key components: 1. Cam-Lock die body; 2. Cam-Lock lever; 3. Stem; and 4. Collet (Caliber-specific).
NOTE: In order to use this tool, you’ll need the appropriate collet for each diameter range of bullets you intend to pull. For example use collet #3 for 6mm, collect #6 for 7mm, and collet #7 for .308 Caliber.
RCBS Lock-Out Die
A good safety option for users with progressive presses is the RCBS Lock-Out Die. This has a charge detection rod that dips into each case after powder has dropped. You adjust the die to the proper charge height for your desired load. If the actual dispensed charge is too high or too low, the Lock-Out Die senses the problem and stops the press from advancing to the next case (it does this by preventing the ram/shellplate from fully elevating). We’ve used the Lock-out die with success for both pistol and rifle cartridges. It’s sensitive to about one-half grain with pistol powders.
This Lock-Out Die works with Hornady and Dillon progressives as well as with RCBS progressives. It does take up one die station on the press.
A while back, Shooting Times released an article entitled “Ten Most Common Reloading Mistakes”. Listed below are the Top Ten mistakes hand-loaders can make, at least according to Shooting Times. What do you think of this list — does it overlook some important items?
Top Ten Reloading Mistakes According to Shooting Times:
1. Cracked Cases — Reloaders need to inspect brass and cull cases with cracks.
2. Dented Cases — Dents or divets can be caused by excess case lube.
3. Excessive Powder Charge — Overcharges (even with the correct powder) can be very dangerous.
4. Primers Not Seated Deep Enough — “High” primers can cause functioning issues.
5. Crushed Primers — Some priming devices can deform primers when seating.
6. Excess Brass Length — Over time, cases stretch. Cases need to be trimmed and sized.
7. Bullets Seated Too Far Out — If the bullet is seated too long you may not even be able to chamber the round. Also, with hunting rounds, bullets should not engage the rifling.
8. Burrs on Case Mouths — Ragged edges on case mouths can actually shave bullet jackets.
9. Excess Crimp — This is a common problem with pistol rounds loaded on progressives. If case lengths are not uniform some cases will get too much crimp, others too little.
10. Inadequate Crimp — This can be an issue with magnum pistol cartridges in revolvers.
Do you agree with this list? We think some important things are missing, such as not adjusting full-length sizing dies properly. This can cause the shoulder to be pushed back too far (or not far enough). Another common mistake is using brass that is worn out, i.e. stretched in the case-head area from multiple cycles of hot loads. We also think the #1 error a reloader can make is using the wrong powder altogether. That can be a fatal mistake. See what happens when you load pistol powder in a rifle.
Here’s a tip we feature every year or so, because it is something that costs nothing, yet can be very useful in the reloading process.
With a simple, easy modification to a fired case, you can determine the length to lands in your rifle barrel. As long as you set the tension right, the measurements should be repeatable, and you’ve just saved yourself $47.40 — the combined cost of a Hornady commercial OAL gauge ($41.41) and Modified Case ($5.99).
To achieve best accuracy with a rifle, you must control bullet seating depth very precisely, so all bullets end up in the same place relative to the entrance of the lands, every time. There may be multiple cartridge OALs which prove accurate. However, with each, you first need to determine a “zero” point — a reliable, and repeatable OAL where the bullet is “just touching” the lands.
There are tools, such as the Hornady (formerly Stoney Point) OAL Gauge, that will help you find a seating OAL just touching the lands. However, the tool requires that you use a special modified case for each cartridge you shoot. And, while we find that the Hornady OAL Gauge is repeatable, it does take some practice to get in right.
Make Your Own Length-to-Lands Gauge with a Dremel
Here’s an inexpensive alternative to the Hornady OAL tool — a slotted case. Forum member Andris Silins explains how to create a slotted case to measure length to the lands in your rifle:
“Here’s what I did to find length to lands for seating my bullets. I made four cuts into the neck of fire-formed brass. Then I pressed the bullet in lightly and chambered the entire gauge. As the cartridge chambers, the bullet slides back into the case to give you length to lands. It took less than five minutes to get it cut and working. A little light oil in the barrel just past the chamber helps ensure the bullet does not get stuck in the lands. It works great and is very accurate.
How to Adjust Tension — Length and Number of Neck Cuts
I made the cuts using a Dremel with a cut-off wheel. You can adjust tension two ways. First, you can make the cuts longer or shorter. Longer cuts = less tension. If you used only three cuts instead of four you would get more tension. The trick is to be gentle when you open and close the bolt. If you ram the bolt closed you may wedge the bullet into the lands. When you open the bolt it helps to keep a finger or two near by to guide the case out straight because the ejector wants to push it sideways.”
Sierra BulletsBallistic Technician Gary Prisendorf has written a nice essay about how reloading can become a life-time hobby, a rewarding pastime that can bring together a father and son…
Memories of My Father — Reloading As a Life-Time Hobby
by Gary Prisendorf
For as long as I can remember I have been around reloading. I have tons of childhood memories of my father reloading and shooting. I remember how he would let me help him load his ammunition, by letting me clean primer pockets or wipe the sizing lube off of his cases. I really thought I was doing something. Well, I guess I was, I was spending quality time with my father doing something that would become a great hobby and eventually land me a great job working for Sierra Bullets.
If you are a reloader, teach someone. You may just give them a hobby for the rest of their life and who knows, you could help them find an enjoyable career, doing something that they love.
— Gary Prisendorf
I remember watching my father sizing cases on his Herters press, dropping his powder charges with a Belding & Mull powder measure and weighing powder charges with his Texan scales. Heck, I can even remember when he would buy powder at a local pawn shop, and they would weigh it out and put it in a paper sack. He would save his empty powder cans, wrap them with masking tape and write what the powder was on them with a black magic marker.
When I was in Junior High, I got my first shotgun, a 20 gauge Mossberg 500 and within a couple of weeks my father came home with a 20 gauge Lee Load-All and a pound of Blue Dot. He gave me a crash course on how to use it, and got me up and running with a couple of safe loads. I put a lot of shells through that old 20 gauge.
From that day forward I was hooked. If I got a new gun, I was loading ammunition for it. I don’t buy factory ammunition unless I just want to shoot it up so I can get some once fired brass. I reload everything that I shoot, except for rimfire stuff, and if I could figure out how to do that safely, I would probably load that too.
Through the years I have learned to appreciate things — such as once-fired military .30-06 cases that can be converted to obscure cartridge types. And I know the value of a five-gallon bucket of lead wheel weights that will be melted down and cast into bullets.
I remember finding 19 once-fired Norma 7.7×58 Arisaka cases laying on the ground at a public shooting range, and it was like Christmas came early. I must have looked for that 20th case for about thirty minutes, but I never did find it.
I can’t thank my father enough for getting me started in reloading, he gave me a great hobby, many wonderful memories and taught me the skills that gave me a career doing something that I love.
L.E. Wilson Case Gage Depth Micrometer Tool Hands-On Tool Review by F-Class John
Are you looking for a better way to measure shoulder bump when sizing brass? When it comes to measuring your shoulder bump there has traditionally been just one way to do it and that’s with a set of calipers and some type of tool attached to a calipers jaw which contacts the case shoulder. While this method has worked well for decades there’s always been some inherent lack of consistency and repeatability. While a minor issue, the inability to get the exact number in completely dependent on the user’s pressure applied and the angle at which the jaws push on the brass.
Enter the L.E. Wilson Case Gage Depth Micrometer with its simple but effective use of Wilson case gauges to ensure a perfect measure of shoulder bump every time. The unit comes with the micrometer top as well as a check gauge which allows you to easily calibrate the micrometer whenever needed. On top of the micrometer unit, you’ll also need to purchase the appropriate case gauges for each of your cartridge types and then you’re ready to go. No other measuring instruments are needed (yep, no calipers are required).
Using the Wilson Depth Micrometer (perhaps a better name is Shoulder Bump Micrometer) is a straightforward process. Simply take your fired brass and insert it into the case gauge and place the micrometer top onto the primer side of the gauge. While holding the micrometer top firmly against the case gauge in one hand, slowly turn the micrometer until you feel it stop. You can back off and turn it again to verify the stop point and once you have it, look at the measurement on the micrometer. Now insert a sized piece of brass and repeat the procedure. Take note of the new number and subtract it from the fired brass number and you now have an exact amount of shoulder bump. Continue to adjust your sizing die until you have the correct amount of shoulder bump and you’re ready to size all your brass.
Watch Video to See how Shoulder-Bump Measuring Micrometer Tool Works
Guys, in this case a VIDEO is worth more than a thousand words. In may not be obvious from the photos how this system works. In fact, it is fast and easy. Drop brass into cartridge-specific case gauge, then put the Micrometer unit on top, and dial to touch. The video shows how this works.
SUMMARY — Tool is Fast, Precise, Repeatable, and Easy to Use — We Like It
The beauty of this tool is the simplicity with which it works. It uses a very accurate micrometer to simply measure how much further your brass is sitting forward inside the case gauge. After a couple uses, you’ll find that this tool is fast, accurate and incredibly repeatable. That gives you confidence that your brass is being sized properly. Ultimately, I found that using the micrometer top really became a joy as I set up a new set of dies and as I sized my brass, I could easily check the consistency as brass came off my press. If you’re looking to improve your sizing game, give the L.E. Wilson Case Gage Depth Micrometer a try. MSRP is $140.00.
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.
Bryan Litz and The Science of Accuracy Academy have released 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.”
Subscriptions for Applied Ballistics The Science of Accuracy Academy Podcasts
If you like this podcast, and want to learn more from Brian Litz and his Applied Ballistics team, you can order a subscription to the Academy. Priced at $9.95/mo, this subscription will allow you to access all podcasts, exclusive videos, learning resources, and bullet data sheets.
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
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:
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.”
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.
Sinclair Internationalhas 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 Accuracyby 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.
Figure 1: The cartridge.
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).
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.
Figure 4: Neck in alignment with center of the case axis.
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″.
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”.
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.
Figure 8: Proper alignment from the center of the case head to the tip of the bullet.
(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.
RCBS Lock-Out Die
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 1
