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December 29th, 2014
 In our Shooters’ Forum a reader asked: “How much neck tension should I use?” This prompted a Forum discussion in which other Forum members recommended a specific number based on their experience, such as .001″, .002″, or .003″. These numbers, as commonly used, correspond to the difference between case-neck OD after sizing and the neck OD of a loaded round, with bullet in place. In other words, the numbers refer to the nominal amount of interference fit (after sizing).
While these commonly-used “tension numbers” (of .001″, .002″ etc.) can be useful as starting points, neck tension is actually a fairly complex subject. The actual amount of “grip” on the bullet is a function of many factors, of which neck-OD reduction during sizing is just one. Understanding these many factors will help you maintain consistent neck tension as your brass “evolves” over the course of multiple reloadings.
Neck Tension (i.e. Grip on Bullets) Is a Complex Phenomenon
While we certainly have considerable control over neck tension by using tighter or looser bushings (with smaller or bigger Inside Diameters), bushing size is only one factor at work. It’s important to understand the multiple factors that can increase or decrease the resistance to bullet release. Think in terms of overall brass-on-bullet “grip” instead of just bushing size.
One needs to understand that bushing size isn’t the beginning and end of neck tension questions, because, even if bushing size is held constant, the amount of bullet “grip” can change dramatically as the condition of your brass changes. Bullet “grip” can also change if you alter your seating depth significantly, and it can even change if you ultrasonically clean your cases.
Bullet grip is affected by many things, such as:
- 1. Neck-wall thickness.
- 2. Amount of bearing surface (shank) in the neck.
- 3. Surface condition inside of neck (residual carbon can act as a lubricant; ultrasonic cleaning makes necks “grabby”).
- 4. Length of neck (e.g. 6BR neck vs. 6BRX).
- 5. Whether or not the bullets have an anti-friction coating.
- 6. The springiness of the brass (which is related to degree of work-hardening; number of firings etc.)
- 7. The bullet jacket material.
- 8. The outside diameter of the bullet and whether it has a pressure ridge.
- 9. The time duration between bullet seating and actual firing (necks can stiffen with time).
- 10. How often the brass is annealed
— and there are others…
Seating Depth Changes Can Increase or Decrease Grip on Bullet
You can do this simple experiment. Seat a boat-tail bullet in your sized neck with .150″ of bearing surface (shank) in the neck. Now remove the bullet with an impact hammer. Next, take another identical bullet and seat it with .300″ of bearing surface in another sized case (same bushing size/same nominal tension). You’ll find the deeper-seated bullet is gripped much harder.
 Neck-Wall Thickness is Important Too
I have also found that thinner necks, particularly the very thin necks used by many PPC shooters, require more sizing to give equivalent “grip”. Again, do your own experiment. Seat a bullet in a case turned to .008″ neckwall thickness and sized down .003″. Now compare that to a case with .014″ neckwall thickness and sized down .0015″. You may find that the bullet in the thin necks actually pulls out easier, though it supposedly has more “neck tension”, if one were to consider bushing size alone.
In practical terms, because thick necks are less elastic than very thin necks, when you turn necks you may need to run tighter bushings to maintain the same amount of actual grip on the bullets (as compared to no-turn brass). Consequently, I suspect the guys using .0015″ “tension” on no-turn brass may be a lot closer to the guys using .003″ “tension” on turned necks than either group may realize.
Toward a Better Definition of Neck Tension
As a convenient short-cut, we tend to describe neck tension by bushing size alone. When a guy says, “I run .002 neck tension”, that normally means he is using a die/bushing that sizes the necks .002″ smaller than a loaded round. Well we know something about his post-sizing neck OD, but do we really have a reliable idea about how much force is required to release his bullets? Maybe not… This use of the term “neck tension” when we are really only describing the amount of neck diameter reduction with a die/bushing is really kind of incomplete.
My point here is that it is overly simplistic to ask, “should I load with .001 tension or .003?” In reality, an .001″ reduction (after springback) on a thick neck might provide MORE “grip” on a deep-seated bullet than an .003″ reduction on a very thin-walled neck holding a bullet with minimal bearing surface in the neck. Bushing ID is something we can easily measure and verify. We use bushing size as a descriptor of neck tension because it is convenient and because the other important factors are hard to quantify. But those factors shouldn’t be ignored if you want to maintain consistent neck tension for optimal accuracy.
Consistency and accuracy — that’s really what this all about isn’t it? We want to find the best neck tension for accuracy, and then maintain that amount of grip-on-bullet over time. To do that you need to look not only at your bushing size, but also at how your brass has changed (work-hardened) with time, and whether other variables (such as the amount of carbon in the neck) have changed. Ultimately, optimal neck tension must be ascertained experimentally. You have to go out and test empirically to see what works, in YOUR rifle, with YOUR bullets and YOUR brass. And you may have to change the nominal tension setting (i.e. bushing size) as your brass work-hardens or IF YOU CHANGE SEATING DEPTHS.
Remember that bushing size alone does not tell us all we need to know about the neck’s true “holding power” on a bullet, or the energy required for bullet release. True bullet grip is a more complicated phenomenon, one that is affected by numerous factors, some of which are very hard to quantify.
December 28th, 2014
This article originally appeared in Sinclair Intl’s Reloading Press Blog, which has been merged into the Gun Tech Section on Sinclair’s website, www.SinclairIntl.com
Steps to Minimize Bullet Run-Out
Poor bullet run-out can cause poor and inconsistent accuracy, and variations in bullet velocities. The truer the loaded round, the more consistent your results will be on paper and across the chronograph.
 Measuring Concentricity
We all know that low run-out is the goal. But how can you tell if your run-out is high or low? Run-out is generally measured in thousandths of an inch with a concentricity gauge. There are many concentricity gauges to choose from that work well. Some work on loaded rounds only, some have a bullet straightening feature, and a few work on both loaded rounds and empty cases for checking case neck concentricity. The tool of choice for the Sinclair Reloading Tech Staff is the Sinclair Concentricity Gauge (Part # 09-175).
This tool is a mainstay on my bench, and it is used about as much as I use my reloading press! The tool uses two sets of bearings that are set on lateral, length-adjustable anodized aluminum blocks to accommodate cartridges from .221 Fireball-sized cases up to .50 BMG. The indicator is set on a height adjustable swiveling base on a stand that can be used for checking bullet or case neck run-out. The adjustable blocks ride aligned in a precision-milled slot. The entire set up is on an anodized base plate that gives excellent support during the process that is crucial to operation and accuracy. Basically the operation consists of placing a loaded round (for checking bullet run-out) or an empty case (for case run-out) on the bearings with the indicator end touching the chosen point to be measured. The case is easily spun with one finger as the indicator measures the amount of run-out. Once this process has been done a few times it is a fast and accurate means of measurement. In terms of indicator type being used, whether dial or digital, I actually prefer a standard dial indicator over the digital type. My reason for this choice is that you can see the needle jump when run-out is present. I believe this to be easier and faster than looking at digital numbers while measuring. In the video below, Sinclair’s Bill Gravatt shows how to use the Sinclair Concentricity Gauge correctly.
Sizing Steps to Minimize Run-Out
One of the most common steps in the reloading process that contributes to bullet run-out occurs is the sizing operation. If improper techniques are used or there are issues with the sizing die set up, a once perfectly concentric case can become out of whack. By using the proper dies for your application, properly setting up the die/shell holder or floating the de-capping/expander assembly, you can eliminate problems before they happen.
 Many of us on the technical staff choose the Redding Type-S series of dies. These are full-Length or neck sizing dies that utilize a removable/changeable neck bushing (sold separately) to size the neck according to your application. These dies are machined with true precision and quality in mind. The Type-S dies come with a standard de-capping assembly with a caliber-specific expander ball in place. In addition to this an undersized retainer to hold the de-capping pin is included with the die. In my experience with these dies I use the standard expander ball with new, unfired brass on the initial re-size. I will then use the undersized retainer in place of the expander ball with brass that has been fired. I have found this step crucial in my reloading regiment to minimize bullet run out. The use of the expander ball can cause a few thousandths of run-out when the case is being pulled back out of the sizing die. With the undersized retainer in place the only thing that touches the neck of the case in sizing is the bushing. If you prefer to use an expander ball, Redding offers caliber specific carbide floating expander balls that fit on the de-capping rod. This free floating expander ball will self center on the case neck, and reduce the amount of run-out that can be caused by a standard expander ball.
When setting up a Type-S sizing die, set the neck bushing into the die with the numbers facing down toward the body of the die. Tighten the de-capping assembly until it contacts the bushing and then back it off ¼ of a turn. This allows the bushing to free float in the die. You should be able to hear the bushing rattle if you shake the die. Having the bushing free floating self centers the neck, and again minimizes any run-out that can occur.
If you prefer other brands of sizing dies there are a few tricks that people use to minimize run-out as well. Many reloaders claim that the use of an O-ring at the base of the de-capping assembly lock nut will float the assembly and help self center during sizing. Another trick that has been used is to remove the retaining pin on the shell holder slot on the press ram, and use an O-ring in its place to hold the shell holder in place. This allows the shell holder to self center during sizing as well.
Seating Steps to Minimize Run-Out
Run-out issues can arise during the bullet seating process. To reduce run-out during seating, use a high-quality die with a sliding sleeve. The sliding sleeve perfectly aligns the case with the bullet to be seated. Good examples of these dies are the Redding Competition Micrometer bullet seating dies, Forster Ultra Seaters, or RCBS Competition Seating dies. All of these dies utilize a micrometer top to precisely set seating depth. They are all very high quality dies that have tight tolerances to maximize bullet straightness during seating.
We receive many questions about seating long pointed bullets such as the Berger VLD or Hornady A-Max. One problem that the reloader faces with longer bullets is that they are so long that the standard seating stem is not machined deep enough to contact these bullets properly. The point of the bullet “bottoms out” in the stem and the result is off-center seating and/or rings and dents on the bullet nose. If you plan on using such bullets, you should purchase a “VLD” style seating stem, which is cut to accommodate the longer bullets. The use of this stem results in truer seating of the bullet without leaving a ring or marring the tip of the bullet.
Besides using a traditional press and threaded seating die, another great way to get a true bullet seat is by using an arbor press and Wilson chamber-type seating die. These dies are cut to very tight tolerances and have proven themselves as the main choice for bench rest enthusiasts. The design of the die positively aligns the case with the bullet as they are both captured by the die before the bullet is pushed straight into the case by the stem. These seating dies are available with the standard seating cap and stem or an additional micrometer top can be added for precise adjustment. Wilson also offers a stainless seating die with an integral micrometer seating head.
Finally another trick used by many in the seating process is to turn the case while the bullet is being seated. Some people claim this will keep things straight. What they do is raise the ram in increments while seating and rotate the case in the shellholder in increments of 90 degrees from the original starting while the bullet is being seated. Personally I have tried this and have seen no significant difference at all. However you may be the judge of this one. It makes sense, and maybe I should try this a little more before I rule it out.
After the Rounds Are Loaded — Batch Sorting by Concentricity Levels
No matter how meticulous you are, and no matter how good your components and tools are, run-out will still show up. Reloaders can drive themselves crazy trying to make each and every loaded round a true “0” in run-out. You will still see some minimal amount no matter what you do. Set yourself a standard of maximum allowable run-out for your loads. For instance for my Long Range 600- and 1000-yard F-Class loads I like to see .002” or less. I average .0015” and see a few in the range up to .004”. I spin each loaded round on my Sinclair Concentricity Gauge and sort them by run-out. Those that run over .002” I use for sighters or practice. Though achieving zero run-out (on every round) isn’t possible, minimizing run-out can definitely help your performance. Not only will your loads shoot better but you will have one less thing to worry about when you are lining up the sights on the target.
December 19th, 2014
The RCBS Rock Chucker is a rugged, classic design that can last a lifetime. If you are looking to get started with hand-loading, or just need another press for your reloading room, the Rock Chucker is a great choice. And now it’s easier than ever to purchase a Rock Chucker. Right now, Bullets.com has slashed the price on its RCBS Rock Chucker Supreme presses. As part of an inventory reduction sale, Bullets.com is now offering the RCBS Rock Chucker Supreme (with full RCBS warranty) for just $99.95. Act soon — this offer is limited to supplies on hand.
More Savings — $10.00 Rebate from RCBS
Getting a great press for under one hundred bucks is hard to beat. But get this — RCBS is currently offering a $10.00 rebate with any qualifying RCBS product purchase of $50.00 or more made before December 31, 2014. So… if you buy this press before the end of 2014, you can get a $10.00 RCBS rebate. That lowers your effective cost to $89.95 for the Rock Chucker Supreme. That is one amazing deal. CLICK HERE for REBATE INFO.
December 8th, 2014
 Christmas is coming up soon, so today we’re featuring a hand-picked collection of “stocking stuffers” for precision shooters. You can order most of these items online, and if you get your orders in soon, your selections should arrive before December 25th. So as not to bust your holiday budget, all of our selections are priced under $10.00. These items are handy tools that you’ll use over and over again at the range and/or at your loading bench (so you’re allowed to buy them for yourself, even after Christmas).
Gifts $1 to $5
Surveyors Tape
$1.99 |
Hood Kwik Estimator
$2.50 |
Bifocal 3X/6X Magnifier
$2.75 |
Barrel Mirage Shade
$4.95 |
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Surveyors’ Tape. Always watch the wind when you shoot. Inexpensive, Day-Glo Surveyors’ Tape (aka “Flagging Tape”), attached to a stake or target frame, makes a good wind indicator. It will flutter even in mild breezes, alerting you to both angle and velocity shifts. This should be part of every range kit. Don’t leave home without it.
Hood Kwik Estimator. Here’s a very handy tool to measure your 6mm groups. Bracket the group within the diverging lines of the Kwik Estimator and you’ll instantly get a good approximation of the actual group size. No more trips to the tool box for calipers. The inexpensive Kwik Estimator fits in a shirt pocket. (Thanks to Boyd Allen for this suggestion.)
Bifocal 3X/6X magnifier. This handy, inexpensive dual-power magnifier is always close at hand on our loading bench, because it helps with so many task. We use a compact magnifier to inspect bullet tips, to check brass chamfers, and inspect the internals of triggers and other parts. Priced at just $2.75, a magnifier like this (or the folding variety) is a “must-have” item for every hand-loader.
Sinclair Barrel Mirage Shade. For high-volume varminters, and competitors who shoot fast in warm weather, a mirage shield is absolutely essential. This prevents hot air rising off the barrel from distorting the image in your scope. The aluminum Sinclair shield can be trimmed to fit, and comes with stick-on Velcro attachments. Two lengths are available: 18″ for short BR barrels, and 24″ for longer barrels.
Gifts $6 to $10
Dewey Crocogator
$6.50 |
Ballistol Aerosol Lube
$8.99 |
Sinclair Barrel Bag
$9.95 |
Sinclair Load Block
$9.99 |
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Dewey Crocogator. The Crocogator tool, with knurled “teeth” at both ends, is simple, inexpensive, and compact. Yet nothing zips though primer-pocket gunk faster or better. Unlike some cutter-tipped primer pocket tools, the Crocogator removes the carbon quick and easy without shaving brass. One end is sized for large primer pockets, the other for small.
Ballistol Aerosol Lube. Ballistol is a versatile, non-toxic product with many uses in the reloading room. We have found it is ideal for lubricating cases for normal full-length sizing. It is clear, not gooey or chalky like other lubes. It is very, very slippery, yet is easy to apply and just as easy to wipe off. As you lube your cases, the Ballistol will also clean powder fouling off the case necks. For heavy-duty case forming and neck expansion, we’ll still use Imperial die wax, but for every-day case sizing, Ballistol is our first choice. It also helps prevent your dies from rusting and it even conditions leather. Ballistol is a favored bore cleaner for Black Powder shooters because it neutralizes acidic powder residues.
 Sinclair Barrel Bag. If you run a switch-barrel rig, or take spare barrels to a big match, this simple but effective barrel bag will protect your valuable steel. The bag is moisture-resistant vinyl on the outside with a soft, quilted interior to protect the barrel’s finish and delicate crown. There are two sizes: one for barrels up to 26 inches, the other for barrels up to 31 inches. Both sizes are priced at $9.95 per bag. That’s cheap insurance for those priceless barrels.
Sinclair ‘Poly’ Loading Block. We’ve tried wood and injection-molded loading trays, and we prefer Sinclair’s white polyethylene loading blocks. They featured chamfered holes properly sized for the particular case you reload. The blocks are heavy enough to be stable on the bench, and the “dishwasher-friendly” material is easy to clean. The standard Poly Loading Block holds 50 cases, while the Competition Loading Block holds 25 cases with a tray for empties. For a bit more money, there’s also a Heavy-Duty 50-case model with an extra-thick 1″ base.
December 4th, 2014
 The 2015 Hodgdon Annual Manual (the 12th Annual Edition) has been released. The 2015 Hodgdon Manual now contains over 5000 loads — more load data than you’ll find in any other annual reloading resource. The 2015 Manual has updates for numerous rifle and pistol cartridges. Featured in the 2015 Manual are the new IMR Enduron™ powders such as IMR 4166, IMR 4451, and IMR 7977. Enduron powders feature a built-in copper fouling reducer, along with small kernels for easy metering and good load density. IMR also claims that Enduron powders are not sensitive to ambient temperature changes. It appears IMR 4166 may be a viable alternative to Hodgdon’s popular, but hard to find, Varget powder.
Along with comprehensive load data, the 8 1/2″ by 11″ magazine-style Hodgdon Annual Manual offers authoritative articles by top gun industry writers. You can purchase the 2015 Manual at news-stands (and gunshops) for $8.99. In a few weeks, you should also be able to purchase the manual from Hodgdon’s online store. For more info, visit Hodgdon.com or call 913-362-9455.
November 29th, 2014
Many shooters prefer to deprime their fired cartridge cases before other operations (such as neck-sizing and full-length sizing). In addition, when cleaning brass with an ultrasonic system, it’s not a bad idea to remove primers first. That way the primer pockets get cleaned during the ultrasonic process.
To deprime cases before sizing or cleaning you can use a Depriming Die (aka “decapping die”). This pushes out the spent primer without changing the neck or body of a case. Such decapping dies work fine, but they do require the use of a press.
New Handheld Primer Removal Tool From Frankford Arsenal
Here’s a new tool that allows you to deprime cartridge cases without a press. This new hand-tool from Frankford Arsenal will deprime (and capture primers) conveniently. You can deprime your cases while watching TV or relaxing in your favorite chair.
This handy depriming tool is very versatile. With a universal, cylinder-style cartridge-holder, the tool can deprime a wide variety of cartridge types from .20 caliber up to .338 caliber. Spent primers are captured in a removable spent primer catch tube. With die-cast metal construction, this tool should last through many thousands of depriming cycles. MSRP is $54.99.
Will This Tool Work with Small Flash Hole Brass?
This new depriming tool will be introduced at SHOT Show in January 2015. We have not been able to measure the decapping shaft diameter, so we do not know whether this hand tool will work with small flash-holes found on Lapua benchrest brass (such as 220 Russian and 6mmBR). We’ll try to answer that question at SHOT Show. This tool is so new the specs are not yet listed on Frankford Arsenal’s website.
Product find by EdLongrange. We welcome reader contributions.
November 19th, 2014
Many shooters, particular those who shoot vintage military rifle matches, reload once-fired military cartridge brass. This brass may be high-quality and stout, but you may encounter a primer crimp* that interferes with the seating of a new primer. There are a variety of dedicated, military-crimp tools on the market, such as Dillon’s excellent Super Swage 600 tool that “rolls the crimp away”. But the Dillon tool costs $100.95 and takes quite a bit of room on your reloading bench. If you don’t want to drop a C-note and give up valuable bench space — here’s another (much cheaper) solution.
If you already have a Wilson case trimmer set-up, you can ream away those military crimps using an affordable Wilson accessory — the Primer Pocket Reamer (large #PPR-210, small #PPR-175). This $32.99 accessory is used in conjunction with a Wilson case trimmer and case-holder as shown below.
 In the older Riflemans Journal website, the Editor, “GS Arizona”, shows how to use the Wilson primer pocket reamer to remove military crimps on Lake City .30-06 cartridge brass. He explains: “The case goes into the Wilson case-holder, the same one used for case trimming, and the reamer replaces the trimmer head in the tool base. The threaded rod on the left side, which is normally used to regulate trim length has no use for this operation and it is simply backed out. Hold the case-holder as you turn the reamer into the primer pocket, it cuts easily and quickly. The reamer will stop cutting when the proper depth is reached.”
 
Do you really need to do this operation with military-crimped brass? Yes, and here’s why: “any attempt to prime the case without removing the crimp will simply result in a mangled primer that cannot be expected to fire and certainly won’t fire reliably.”
Read Full Article on Riflemans’ Journal Website (more photos and detailed write-up).
*Why does military brass has a primer crimp? GS Arizona answers: “The crimp is nothing more than an intentional deformation of the case around the primer pocket, the purpose of which is to retain the primer in the case despite high pressure situations in machine guns and other automatic weapons where a loose primer may cause a malfunction. As reloaders, our task is to get rid of the remnants of the crimp in order to allow re-priming the case.”
November 16th, 2014
Most of us assume that if we weigh our powder carefully (down to the tenth of a grain or less) we can achieve a uniform powder fill from case to case in our handloads. Weighing does ensure that the weight of the propellant in each case is the same, but is the column of powder the same by volume each time? “Not necessarily” is the answer. An interesting experiment by our friend Boyd Allen demonstrates that the manner in which you place kernels in the case can make a significant difference in the height of the powder column within the brass case.
Using a Gempro 250 scale, Boyd measured exactly 30.6 grains of Vihtavuori N-133 powder. He then inserted this powder in the same cartridge case multiple times. (The case has a fired primer in place.) But here is the key — Boyd used various filling techniques. He did a slow fill, and a fast fill, and he also experimented with tapping and drop tubes. What Boyd discovered was that you can start with the exact same weight of powder (in fact the very same set of kernels), yet end up with vary different fill heights, depending on how you drop the kernels into the case. Look at the photos. Despite variations in lighting, the photos show the same 30.6 grains of powder, placed in the same cartridge, with four different methods.
Boyd Explains the Procedure Used for his Experiment.
EDITOR’s NOTE: So there is no misunderstanding, Boyd started with a weighed 30.6 grain charge. This identical charge was used for ALL four fills. After a fill the powder was dumped from the case into a pan which was then used for the next fill technique to be tried. So, the powder weight was constant. Indeed the exact same kernels (of constant weight and number) were used for each fill.
Boyd writes: “I used the same powder for all fills, 30.6 gr. on a GemPro 250 checked more than once. All fills employed the same RCBS green transparent plastic funnel. The fast drop with the funnel only overflowed when it was removed from the case neck, and 15 granules of powder fell on the white paper that the case was sitting on. The fast-funnel-only drop with tapping, was done with the funnel in place and the case and funnel in one hand, while tapping the case body with the index finger hard, many times (about 20 fast double taps). My idea here was to “max out” the potential of this tapping technique.
The slow drop with the funnel and 10″-long .22 cal. Harrell’s Precision drop tube, was done by holding the scale pan over the funnel and tapping the spout of the pan repeatedly on the inside of the funnel about 1/3 down from the top, with the scale pan tilted just enough so that the powder will just flow. Many taps were involved, again, to max out the technique.
Again, to be clear, after each case filling, the powder was poured from the case back into the scale pan carefully. You may notice the similarity between the fast drop with the drop tube, and the funnel only with tapping. Although I did not photograph it, fast tube drop and tapping (combined) improved on tapping alone, but only to about half as far down the neck as the slow with drop tube. Due to the endless possible permutations, I picked four and left it at that.
I believe that I can make the rough judgment that the scale pan funnel and drop tube technique, which involved a longer drop period, and probably less velocity at the top of the tube, left more room in the top of the case neck than the slow drop from the measure with the same drop tube. You have both pictures, so you can make the comparison.” — Boyd
Does Powder Column Height Variance Make a Difference?
Boyd’s experiment proves pretty conclusively that the method of dropping a given weight of powder can affect the height of the powder column in the case and the degree of powder compression (when a bullet is seated). He showed this to be true even when the exact same set of kernels (of constant weight) was used in repetitive loadings. This raises some interesting questions:
1. Will subsequent cartridge transport and handling cause the powder to settle so the variances in powder column height are diminished?
2. If significant inconsistencies in powder column height remain at time of firing, will the difference in fill level hurt accuracy, or result in a higher extreme spread in velocity?
3. Is there any advantage (beyond increased effective case capacity) for a tight (low level) fill vs. a loose (high level) fill?
We don’t know the answer to these follow up questions. This Editor guesses that, if we tested low-fill-height rounds vs. high-fill-height rounds (all with same true fill quantity by weight), we might see meaningful differences in average velocity. I would also guess that if you fired 10 rounds that exhibited quite a difference in powder column heights, you might see a higher ES/SD than if you shot 10 rounds loaded with a very consistent powder column height (either high or low). But further testing is needed to determine if these predictions are true.
November 15th, 2014
How much can you save reloading your own ammo? Well that depends on the cost of components and how much you have invested in your reloading gear. UltimateReloader.com has created a handy online Reloading Costs Calculator that lets you quickly compare the cost of reloaded ammo vs. factory ammo. Just enter the costs of powder, primers, bullets, and brass, and the Calculator will tell you the cost per round, per 20-rd box, per 50-rd box, and cost per thousand. Note — when setting the price of the brass you need to divide the initial cost by the number of predicted reloads. For example if you have 500 pieces of brass that cost $40/100 to buy ($200 total), but you get 8 reloads per case, then you put $25.00 in the Calculator ($200 total brass cost divided by 8).
True Reloading Cost Should Include Amortized Tool Expenses
Ah… but there is a catch. To understand the true cost of reloading, you also need to consider the costs of your tools and accessories, amortized over the tools’ loading lifespan. Let’s say you have $1000.00 invested in presses, dies, tumblers, measuring tools and other accessories, with a residual value of $500.00 (upon resale). If you load 5,000 rounds with those tools over their lifespan, you need to add $0.10 per round for tooling costs (your investment minus residual value, divided by the number of rounds loaded). The UltimateReloader.com Calculator does not include amortized tooling costs, but that’s something you can easily figure out on your own.
Excellent Resource for Reloading Videos
After you’ve tried out the Reloading Costs Calculator, check out the other content on UltimateReloader.com. This site features some of the best gun-related “how-to” videos on the internet. With sharp video and clear audio, the production quality is very high. If you use a progressive press (Dillon, Hornady, RCBS), you should definitely watch UltimateReloader.com’s videos — you’ll probably learn a new trick or two. In the sample video below, you can see how Hornady’s new Bullet Feeder works with its Lock-N-Load Progressive press.
October 26th, 2014
 Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2
by Bryan Litz for Berger Bullets.
Part One of this series focused on the importance of COAL in terms of SAAMI standards, magazine lengths, seating depths, and pressure levels. Another measure of length for loaded ammunition is highly important to precision, namely Cartridge Base to Bullet Ogive Length (CBTO).
Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.
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.
Figure 4. Two different bullet shapes, 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 riflings.
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″.
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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.
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