December 19th, 2014

Awesome Deal: RCBS Rock Chucker Supreme for $99.95

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.

RCBS Rock Chucker Supreme Press Sale bullets.com reloading rebate

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.

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December 8th, 2014

Stocking Stuffers for Shooters — Eight Items Each Under $10.00

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 quick estimator group size gauge
Hood Kwik Estimator
$2.50
Edmunds bifocal Magnifier
Bifocal 3X/6X Magnifier
$2.75
Sinclair Barrel Mirage Shade
Barrel Mirage Shade
$4.95

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 multi-purpose gun lube
Ballistol Aerosol Lube
$8.99
Sinclair Barrel Storage Bag
Sinclair Barrel Bag
$9.95

Sinclair Load Block
$9.99

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.

Santa Christmas Stocking giftsSinclair 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.

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December 4th, 2014

Hodgdon 2015 Annual Manual Features 5000+ Loads

Hodgdon 2015 Reloading Manual annual load dataThe 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.

Permalink News, Reloading No Comments »
November 29th, 2014

New Hand Depriming Tool from Frankford Arsenal

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.

deprime deprimer, de-prime decap decapper primer Frankford Redding Lee priming die

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.
Permalink New Product, Reloading 1 Comment »
November 21st, 2014

Zediker Reloading Book — Worth Checking Out

Glen Zediker Competition Reloading bookForum member Danny Reever and this Editor recently discussed how novice reloaders can struggle with the fine points of reloading, making errors in seating depth, bushing choice, or sizing their cases. We agreed that a good resource covering more than “Reloading Basics” is sorely needed. Danny reminded me that Glen Zediker’s excellent Handloading for Competition book has been available since 2002. Danny says this may still be the best guide in print for those getting started in precision reloading, though the book is not without flaws.

Danny observed: “I consider this still the best book out there on the subject. I’ve bought a lot of other books only to be sorely disappointed after spending $30-$40 of my hard-earned cash. This book is not one of those! I’ve read and re-read Zediker’s treatise at least four times and refer to it often for advice while reloading. My number one suggestion for those who buy the book is to sit down with a highlighter and read it cover to cover. It’s well-written with a bit of humor and it is not boring.”

Extremely comprehensive, Zediker’s book covers nearly all of the key factors involved in accurate reloading: case sorting, brass prep, load development, neck-sizing, full-length sizing, bushing selection/use, tool selection, priming, powder measurement, and bullet seating. The book also explains how to test and evaluate your ammo, and how to monitor and interpret pressure signs.

There are many “must-read” sections in Zediker’s book, according to Danny: “The section beginning on page 161 dealing with concentricity (and how to achieve it) is excellent. Likewise the Load Limits section discussing pressures offers very valuable advice and info. You should also read Zediker’s commentaries about load testing, powders (burn characterics etc.), and the effects of temperature.”

Zediker competition reloading book

CLICK HERE to view book contents and sample pages.

Zediker has conveniently provided a detailed summary of his book on the web, complete with table of contents, sample pages (PDF format), and dozens of illustrations. Shown above is just one small section that covers ejectors.

Overall, we recommend Glen Zediker’s Handloading for Competition, though the book definitely could use some updating. Danny says: “Plunk down the [money] and buy this book, you won’t be sorry.” Zediker’s book is available from Amazon.com ($22.11), Sinclair Int’l ($28.99), and Zediker Publishing ($34.95).

Permalink Reloading 4 Comments »
November 19th, 2014

Remove Military Primer Crimp with Wilson Primer Pocket Reamer

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.

Military crimp primer pocket reamer salazar

Military crimp primer pocket reamer salazarOn his Riflemans Journal website, German Salazar shows how to use the Wilson primer pocket reamer to remove military crimps on Lake City .30-06 cartridge brass. German 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.”

Military crimp primer pocket reamer salazarMilitary crimp primer pocket reamer salazar

Do you really need to do this operation with military-crimped brass? Yes. German cautions: “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? German 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.”

Permalink Bullets, Brass, Ammo, Reloading 3 Comments »
November 16th, 2014

Advanced Reloading: Controlling Cartridge Powder Column Height

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.

Permalink Reloading, Tech Tip 4 Comments »
November 15th, 2014

UltimateReloader.com Reloading Cost Calculator

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).

ultimate reloader cost calculator

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.

YouTube Preview Image
Permalink - Videos, Bullets, Brass, Ammo, Reloading 8 Comments »
November 1st, 2014

Tools and Techniques for Measuring Cartridge Brass

German Salazar has written a very thorough guide to measuring nearly all the critical dimensions of cartridge brass. In his Measuring the Case article, on his Rifleman’s Journal website, German reviews the tools and techniques required to measure everything from case overall length to case neck concentricity. Step-by-step, German shows how to measure: Case Length, Case Body length (below neck), Neck Diameter, Headspace, Base Diameter, Neck Thickness, and Case Neck Concentricity.

Measuring Cartridge Brass

If you are an “advanced reloader” or want to be, you should read German’s article. Not only does German explain the most common measuring procedures, he highlights some alternative methods you might not have tried yet. The article also links to related discussions of more complex measurement tasts, such as determining case body wall thickness variation.

Measuring Cartridge Brass

Even if you’re not a competitive shooter, measuring your brass can provide important safety benefits. As German explains in the conclusion of his article: “There are obviously a lot of measurements that can be taken on the cartridge case and in some cases, more than one way to take them. However, the first two that any new reloader must learn are case length and neck clearance, these two are safety concerns and if overlooked can results in serious damage to the rifle and injury to you.”

German’s article first appeared in RiflemansJournal.com in 2010.
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October 26th, 2014

Berger Article on COAL and Cartridge Base-to-Ogive PART 2

Berger Bullets COAL length cartridgeEffects 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.
chamber length loading berger bullets

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.

chamber length loading berger bullets

Benefits of Having a Uniform CBTO
There is another aspect to knowing your CBTO when checking your COAL as it pertains to performance. With good bullets, tooling, and carefully-prepared cases you can easily achieve a CBTO that varies less than +/- .001″ but your COAL can vary as much as .025″ extreme spread (or more with other brands). This is not necessarily bad and it is much better than the other way around. If you have a CBTO dimension that varies but your COAL dimension is tight (within +/- .002″) then it is most likely that your bullet is bottoming out inside the seater cone on the bullet tip. This is very bad and is to be avoided. It is normal for bullets to have precisely the same nose shape and it is also normal for these same bullets to have nose lengths that can vary as much as .025″.

Summary of Cartridge Base To Ogive (CBTO) Discussion
Here are four important considerations regarding bullet seating depth as it relates to CBTO:

1. CBTO is a critical measurement to understand for handloaders because it’s directly related to precision potential, and you control it by simply setting bullet seating depth.

2. Tools and methods for measuring CBTO vary. Most of the measurement techniques have pitfalls (which may give rise to inconsistent results) that you should understand before starting out.

3. A CBTO that produces the best precision in your rifle may not produce the best precision in someone else’s rifle. Even if you have the same rifle, same bullets, same model of comparator gauges, etc. It’s possible that the gauges are not actually the same, and measurements from one don’t translate to the same dimension for another.

4. Once you find the CBTO that produces the best precision in your rifle, it’s important to allow minimal variation in that dimension when producing quality handloads. This is achieved by using quality bullets, tooling, and properly preparing case mouths and necks for consistent seating.

CLICK HERE to Read Full Article with More Info
Article sourced by EdLongrange. We welcome tips from readers.
Permalink Bullets, Brass, Ammo, Reloading 6 Comments »
October 13th, 2014

CUP vs. PSI — What’s The Difference in Pressure Measurements

by Philip Mahin, Sierra Bullets Ballistic Technician
This article first appeared in the Sierra Bullets Blog

The ANSI / SAAMI group, short for “American National Standard Institute” and “Sporting Arms and Ammunition Manufacturers’ Institute”, have made available some time back the voluntary industry performance standards for pressure and velocity of centerfire rifle sporting ammunition for the use of commercial manufacturers. [These standards for] individual cartridges [include] the velocity on the basis of the nominal mean velocity from each, the maximum average pressure (MAP) for each, and cartridge and chamber drawings with dimensions included. The cartridge drawings can be seen by searching the internet and using the phrase ‘308 SAAMI’ will get you the .308 Winchester in PDF form. What I really wanted to discuss today was the differences between the two accepted methods of obtaining pressure listings. The Pounds per Square Inch (PSI) and the older Copper Units of Pressure (CUP) version can both be found in the PDF pamphlet.

SAAMI CUP PSI Cartridge Copper Units Pressure PSI
Image by ModernArms, Creative Common License.

SAAMI CUP PSI Cartridge Copper Units Pressure PSICUP Pressure Measurement
The CUP system uses a copper crush cylinder which is compressed by a piston fitted to a piston hole into the chamber of the test barrel. Pressure generated by the burning propellant causes the piston to move and compress the copper cylinder. This will give it a specific measurable size that can be compared to a set standard. At right is a photo of a case that was used in this method and you can see the ring left by the piston hole.

PSI Pressure Measurement
What the book lists as the preferred method is the PSI (pounds per square inch or, more accurately, pound-force per square inch) version using a piezoelectric transducer system with the transducer flush mounted in the chamber of the test barrel. Pressure developed by the burning propellant pushes on the transducer through the case wall causing it to deflect and make a measurable electric charge.

Q: Is there a standardized correlation or mathematical conversion ratio between CUP and PSI values?
Mahin: As far as I can tell (and anyone else can tell me) … there is no [standard conversion ratio or] correlation between them. An example of this is the .223 Remington cartridge that lists a MAP of 52,000 CUP / 55,000 PSI but a .308 Winchester lists a 52,000 CUP / 62,000 PSI and a 30-30 lists a 38,000 CUP / 42,000 PSI. It leaves me scratching my head also but it is what it is. The two different methods will show up in listed powder data[.]

So the question on most of your minds is what does my favorite pet load give for pressure? The truth is the only way to know for sure is to get the specialized equipment and test your own components but this is going to be way out of reach for the average shooter, myself included. The reality is that as long as you are using printed data and working up from a safe start load within it, you should be under the listed MAP and have no reason for concern. Being specific in your components and going to the load data representing the bullet from a specific cartridge will help get you safe accuracy. [With a .308 Winchester] if you are to use the 1% rule and work up [from a starting load] in 0.4 grain increments, you should be able to find an accuracy load that will suit your needs without seeing pressure signs doing it. This is a key to component longevity and is the same thing we advise [via our customer service lines] every day. Till next time, be safe and enjoy your shooting.

SAAMI CUP PSI Cartridge Copper Units Pressure PSI

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October 5th, 2014

New Gun Digest Shooter’s Guide to Reloading

We recommend that all hand-loaders have a couple reliable reloading manuals as reference guides. Berger, Hornady, and Sierra all offer well-respected load manuals. These can provide starting load information for a wide variety of cartridge types and bullet selections. We do like to cross-check any printed load recipes with current online data, to ensure you have the latest info.

Along with a good load manual, those getting started in metallic cartridge reloading can benefit from a good basic reloading treatise. There’s a new intro guide from the publishers of Gun Digest.

Guide to Reloading Book

The New Gun Digest Shooter’s Guide To Reloading, by Phillip Massaro, was created for shooters new to reloading. This is a good starting point for those who want to learn to hand-load safely and efficiently. Hundreds of photos illustrate the text — and we all know a picture can be worth a thousand words.

After discussing the benefits of hand-loading, Massaro’s book covers the basics of metallic cartridge reloading, step by step. Along the way Massaro recommends appropriate presses and tools for reloading both pistol and rifle cartridges. Massaro also explains the variations in bullet and powder types, and how they affect ballistics. In addition, Massaro includes a “Specialty Situations” chapter that reveals common reloading mistakes and issues and offers practical solutions. This section on avoiding common mistakes is one of book’s best features. We wish all reloading guides had a similar section.

Editor’s NOTE: This book will be released next week. Accordingly, we have not seen the final, printed version yet. At $14.79, the Gun Digest Shooter’s Guide to Reloading is relatively inexpensive. The sample chapters we reviewed provided good basic information in a well-organized fashion. Certainly, we would not tell advanced reloaders and/or competition shooters to rush out and buy this book. However, for folks getting started in hand-loading, this resource should be helpful.

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