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August 1st, 2016
What happens inside a rifle chamber and barrel when a cartridge fires can’t be seen by the naked eye (unless you are a Super-Hero with X-Ray vision). But now, with the help of 3D-style computer animation, you can see every stage in the process of a rifle round being fired.
In this amazing video, X-Ray-style 3D animation illustrates the primer igniting, the propellant burning, and the bullet moving through the barrel. The video then shows how the bullet spins as it flies along its trajectory. Finally, this animation shows the bullet impacting ballistic gelatin. Watch the bullet mushroom and deform as it creates a “wound channel” in the gelatin. This excellent video was commissioned by Czech ammo-maker Sellier & Bellot to demonstrate its hunting ammunition. The design, 3D rendering, and animation was done by Grafické studio VLADO.
Watch Video – Cartridge Ignition Sequence Starts at 1:45 Time-Mark
Video find by Seb Lambang. We welcome reader submissions.
May 19th, 2016
 Hodgdon Powder Company (Hodgdon) offers a series of professionally produced how-to videos on its popular Reloading Data Center. These 3.5-minute videos present rifle, pistol, and shotshell reloading basics in an easy-to-understand,step-by-step format. These mobile-friendly, informative videos can also be viewed on a smart phone or tablet.
To watch the reloading videos go to the Reloading Data Center at hodgdon.com. Click to the right/left of the displayed video to switch between pistol, rifle, and shotgun videos. Or, for your convenience, we have embedded the Rifle and Pistol videos here. Just click to watch!
Click to Watch Hodgdon Rifle Reloading Video:
Click to Watch Hodgdon Pistol Reloading Video:
In addition to these videos, Hodgdon’s Reloading Data Center (RDC) provides a wealth of information on Hodgdon®, IMR®, and Winchester® propellants. Along with reliable load data, you’ll find explanations of reloading basics, safety procedures, plus answers to frequently asked questions (FAQ).
March 26th, 2016
 
What is “Overbore”? That’s a question rifle shooters can debate to no end. This article from our archives proposes one way to identify “overbore cartridges”. We think the approach outlined here is quite useful, but we know that there are other ways to define cartridges with “overbore” properties. Whenever we run this article, it stimulates a healthy debate among our readers — and that is probably a good thing.
Forum Member John L. has been intrigued by the question of “overbore” cartridges. People generally agree that overbore designs can be “barrel burners”, but is there a way to predict barrel life based on how radically a case is “overbore”? John notes that there is no generally accepted definition of “overbore”. Based on analyses of a wide variety of cartridges, John hoped to create a comparative index to determine whether a cartridge is more or less “overbore”. This, in turn, might help us predict barrel life and maybe even predict the cartridge’s accuracy potential.
John tells us: “I have read countless discussions about overbore cartridges for years. There seemed to be some widely accepted, general rules of thumb as to what makes a case ‘overbore’. In the simplest terms, a very big case pushing a relatively small diameter bullet is acknowledged as the classic overbore design. But it’s not just large powder capacity that creates an overbore situation — it is the relationship between powder capacity and barrel bore diameter. Looking at those two factors, we can express the ‘Overbore Index’ as a mathematical formula — the case capacity in grains of water divided by the area (in square inches) of the bore cross-section. This gives us an Index which lets us compare various cartridge designs.”
OVERBORE INDEX Chart
So what do these numbers mean? John says: “My own conclusion from much reading and analysis is that cartridges with case volume to bore area ratio less than 900 are most likely easy on barrels and those greater than 1000 are hard on barrels.” John acknowledges, however, that these numbers are just for comparison purposes. One can’t simply use the Index number, by itself, to predict barrel life. For example, one cannot conclude that a 600 Index number cartridge will necessarily give twice the barrel life of a 1200 Index cartridge. However, John says, a lower index number “seems to be a good predictor of barrel life”.
John’s system, while not perfect, does give us a benchmark to compare various cartridge designs. If, for example, you’re trying to decide between a 6.5-284 and a 260 Remington, it makes sense to compare the “Overbore Index” number for both cartridges. Then, of course, you have to consider other factors such as powder type, pressure, velocity, bullet weight, and barrel hardness.
Overbore Cases and Accuracy
Barrel life may not be the only thing predicted by the ratio of powder capacity to bore cross-section area. John thinks that if we look at our most accurate cartridges, such as the 6 PPC, and 30 BR, there’s some indication that lower Index numbers are associated with greater inherent accuracy. This is only a theory. John notes: “While I do not have the facilities to validate the hypothesis that the case capacity to bore area ratio is a good predictor of accuracy — along with other well-known factors — it seems to be one important factor.”
February 8th, 2016
We are often asked, “Can you recommend a good reloading book that picks up where the typical reloading manual leaves off — something that goes into more detail about the processes involved.” There is such a book, and it’s fairly recent: Metallic Cartridge Handloading: Pursuit of the Perfect Cartridge, by M.L. (“Mic”) McPherson. Released in 2013, this 425-page book goes into greater depth than McPherson’s popular intro reloading guide, Metallic Cartridge Reloading. McPherson’s latest reloading treatise covers all aspects of the reloading process: the cartridge case; maintaining, improving and loading the case; the seating and reading of primers; the loading of propellant; bullets and the loading of bullets; accurate load development; internal and external ballistics; bullet making and casting; and reloading presses.
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With hundreds of photos and illustrations, this book is a good reference for shooters getting started in precision reloading for accuracy. Compared to some other books on reloading procedures, McPherson’s new resource is more up-to-date, so it references more modern reloading tools and techniques. NOTE: This is NOT a reloading manual containing specific load data. Rather, it is a how-to book that covers the process of cartridge reloading from start to finish.
Reviews by actual book buyers:
A great resource for handloaders although a little technical for beginners. I have been reloading for 40+ years and picked up some good ideas. — Loren R.
This is a book intended for people who have been reloading for a while. The book contains very detailed information about reloading. — Kaj H.
About the Author, M.L. (“Mic”) McPherson:
Mic McPherson, Technical Editor of Hand Loader’s Digest, is the author of numerous firearms resource books including Metallic Cartridge Reloading and Accurizing the Factory Rifle. He has written scores of articles for leading gun periodicals including Precision Shooting, The Accurate Rifle, Rifle Shooter, and Varmint Hunter Magazine. Mic also served as an Editor of the 8th and 9th Editions of Cartridges of the World.
January 11th, 2016
Here’s an item of interest to hunters (and maybe a few F-Open shooters). Nosler has just introduced a new magnum-type cartridge, the 30 Nosler. Sharing the same parent case as the 26 and 28 Nosler® cartridges, the 30 Nosler® has the case capacity to launch big 30-caliber bullets at impressive velocities (3000 FPS for a 210-grainer). Nosler says the 30 Nosler combines the best qualities of other 30-cal magnums: “The 30 Nosler® easily meets the velocity of the 300 Weatherby, headspaces on the shoulder like a 300 RUM, has an efficient powder column like the 300 WSM and fits in the same standard length action of a 300 Winchester Magnum.”
30 Nosler Will Function in a Standard Length Action
The 30 Nosler has a C.O.A.L. of 3.340″ allowing this cartridge to be operated in a standard length action for lighter weight and shorter bolt throw when compared to magnum-length actions.
The 30 Nosler is a SAAMI-standardized cartridge so there will be standardized dimensions for brass, dies, and chamber reamers. Nosler will support this new cartridge with Nosler Brass, Trophy Grade™ Ammunition and a series of M48 hunting rifles. The initial offerings in Nosler’s Trophy Grade™ Ammunition will be:
Nosler® Trophy Grade™ Ammunition: 180gr AccuBond® 3200 fps
Nosler® Trophy Grade™ LR Ammunition: 210gr AccuBond® LR 3000 fps
November 25th, 2015
Here’s something you don’t see very often — Lapua cartridge brass on sale. As part of its Back-to-Black promotion, Brownells has deeply discounted its inventories of Lapua Brass. For most cartridges/calibers, the price has been reduced at least $10.00 per 100-count box. Here are the sale prices, good through the end of the week:
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.222 Rem – $53.99 (reg. $61.99)
.223 Rem – $53.99 (reg. $61.99)
220 Russian – $89.99 (reg. $99.99)
.22-250 – $89.99 (reg. $99.99)
6mmBR – $81.99 (reg. $91.99)
.243 Winchester – $89.99 (reg. $99.99)
6.5 Grendel – $89.99 (reg. $99.99)
6.5×47 Lapua – $99.99 (reg. $109.99) |
260 Remington – $89.99 (reg. $99.99)
6.5×55 Swedish – $71.99 (reg. $81.99)
6.5-284 – $109.99 (reg. $124.99)
7.62×39 – $54.99 (reg. $59.99)
.308 Winchester – $69.99 (reg. $79.99)
.308 Win Palma – $76.99 (reg. $86.99)
.30-06 Springfield – $99.99 (reg. $109.99)
.338 Lapua Magnum – $239.99 (reg. $269.99) |
October 23rd, 2015
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion.
Cartridge Efficiency: A Primer (pun intended!) by USAMU Staff
Each week, the U.S. Army Marksmanship Unit (USAMU) publishes a reloading article on its Facebook Page. In this week’s article, the USAMU discusses cartridge case efficiency and its benefits. While this is oriented primarily toward NRA High Power Rifle and Long Range (1000-yard) competition, these factors also apply to medium/big game hunters. Assuming one’s rifle and ammunition are accurate, key considerations include ballistic performance (i.e., resistance to wind effects, plus trajectory), recoil, and throat erosion/barrel life.
Efficient cartridges make excellent use of their available powder and case/bore capacity. They yield good ballistic performance with relatively little recoil and throat erosion. A classic example in the author’s experience involved a featherweight 7x57mm hunting/silhouette rifle. When loaded to modern-rifle pressures, just 43-44 grains of powder pushed a 139gr bullet at 2900 fps from its 22” barrel. Recoil in this light rifle was mild; it was very easy to shoot well, and its performance was superb.
An acquaintance chose a “do everything” 7mm Remington Magnum for use on medium game at short ranges. A larger, heavier rifle, it used ~65 grains of powder to achieve ~3200 fps with similar bullets — from its 26″ barrel. Recoil was higher, and he was sensitive to it, which hampered his shooting ability.
Similarly efficient calibers include the 6mm BR [Norma], and others. Today’s highly-efficient calibers, such as 6mm BR and a host of newer developments might use 28-30 grains of powder to launch a 105-107gr match bullet at speeds approaching the .243 Winchester. The .243 Win needs 40-45 grain charges at the same velocity.
Champion-level Long Range shooters need every ballistic edge feasible. They compete at a level where 1″ more or less drift in a wind change could make the difference between winning and losing. Shooters recognized this early on — the then-new .300 H&H Magnum quickly supplanted the .30-06 at the Wimbledon winner’s circle in the early days.
The .300 Winchester Magnum became popular, but its 190-220gr bullets had their work cut out for them once the 6.5-284 and its streamlined 140-142gr bullets arrived on the scene. The 6.5-284 gives superb accuracy and wind performance with about half the recoil of the big .30 magnums – albeit it is a known barrel-burner.
Currently, the 7mm Remington Short Action Ultra-Magnum (aka 7mm RSAUM), is giving stellar accuracy with cutting-edge, ~180 grain bullets, powder charges in the mid-50 grain range and velocities about 2800+ fps in long barrels. Beyond pure efficiency, the RSAUM’s modern, “short and fat” design helps ensure fine accuracy relative to older, longer cartridge designs of similar performance.
Recent design advances are yielding bullets with here-to-fore unheard-of ballistic efficiency; depending on the cartridge, they can make or break ones decision. Ballistic coefficients (“BC” — a numerical expression of a bullet’s ballistic efficiency) are soaring to new heights, and there are many exciting new avenues to explore.
The ideal choice [involves a careful] balancing act between bullet BCs, case capacity, velocity, barrel life, and recoil. But, as with new-car decisions, choosing can be half the fun!
Factors to Consider When Evaluating Cartridges
For competitive shooters… pristine accuracy and ballistic performance in the wind are critical. Flat trajectory benefits the hunter who may shoot at long, unknown distances (nowadays, range-finders help). However, this is of much less importance to competitors firing at known distances.
Recoil is an issue, particularly when one fires long strings during competition, and/or multiple strings in a day. Its effects are cumulative; cartridges with medium/heavy recoil can lead to shooter fatigue, disturbance of the shooting position and lower scores.
For hunters, who may only fire a few shots a year, recoil that does not induce flinching during sight-in, practice and hunting is a deciding factor. Depending on their game and ranges, etc., they may accept more recoil than the high-volume High Power or Long Range competitor.
Likewise, throat erosion/barrel life is important to competitive shooters, who fire thousands of rounds in practice and matches, vs. the medium/big game hunter. A cartridge that performs well ballistically with great accuracy, has long barrel life and low recoil is the competitive shooter’s ideal. For the hunter, other factors may weigh more heavily.
Cartridge Efficiency and Energy — Another Perspective
Lapua staffer Kevin Thomas explains that efficiency can be evaluated in terms of energy:
“Cartridge efficiency is pretty straight forward — energy in vs. energy out. Most modern single-based propellants run around 178-215 ft/lbs of energy per grain. These figures give the energy potential that you’re loading into the rifle. The resulting kinetic energy transferred to the bullet will give you the efficiency of the round. Most cases operate at around 20-25% efficiency. This is just another way to evaluate the potential of a given cartridge. There’s a big difference between this and simply looking at max velocities produced by various cartridges.”
September 8th, 2015
“Once-fired, lot-number-traceable Lake City 7.62×51. This has been de-primed, pocket-swaged, small base body die’d, full-length sized, trimmed with a Gracey Trimmer, and tumbled. Now it’s shiny again. It’s like gourmet macaroni for shooters!” — Dennis Santiago
Our friend Dennis Santiago shoots a variety of disciplines, including Vintage Military Rifle. He burns through a lot of brass, some of it run through gas guns, so he often saves money by acquiring once-fired Lake City Arsenal brass. But that stuff is often pretty ugly when it arrives. For his “previously-owned” Lake City Brass, Dennis does a complete case prep operation and a thorough cleaning/tumbling operation. Special attention is paid to the primer pockets — they are swaged to remove the military crimp. The cases are trimmed and chamfered in one operation using a Gracey Powered Case Trimmer.
Dennis likes once-fired Lake City brass for some applications. The price is right, and with proper attention to detail during case prep, Lake City brass can shoot exceptionally well indeed. You may want to sort Lake City brass by weight. To remove the military crimp you have a variety of options — you can swage it out with a special tool like Dennis does, or you can ream out the crimp. For Wilson trimmer owners, Wilson makes a special Primer Pocket Reamer to remove military crimps. It works very well, as shown below:
 
Case Processing with the Gracey Trimmer
Designed by Doyle Gracey 30 years ago, the Gracey machine trims, deburs and chamfers in one operation, indexing off the case shoulder. The manufacturer claims the Gracey will process 20 cases per minute while holding .002″ tolerances on trim length. Two steel cutters are employed — one cutter trims the case to length and puts a chamfer on the inside of the case mouth. The second cutter removes the burr from the outside of the case-mouth. A 1/15 hp motor turns 1550 rpm. Interestingly, a clamped rubber hose serves as the “drive shaft” to turn the cutting head.
Trey Tuggle, writing in Shooting Sports USA, reviewed the Gracey Trimmer, giving it generally high marks, though it lacks some of the refinements of the more modern Giraud Trimmer:
“This model may have a piece of wood for a base, no on-off swith and a piece of bent sheet metial to contain brass shavings — but it does trim, debur and chamfer with great speed and accuracy at a nice price. The [Gracey] two-bladed cutter requires a little more patience to adjust than the one-piece cutter on the Giraud, but it gets the job done superbly. [The Gracey] does the job for less money, if you’re willing to tinker with the cutter blade adjustment.” Gracey machines are still available new from MatchPrep.com for $335.00 (or $235.00 without motor).
April 22nd, 2015
OK, guys, it’s time to practice your downloading skills. Here’s a very handy cartridge information sheet you will definitely want to save for future reference. Shown below is Page One of the Primer Size and Bullet Diameter Chart created by Graf & Sons. This chart shows the bullet diameter and primer size for more than 320 popular cartridges*. The full three-page chart is available in PDF format for easy printing.
DOWNLOAD Graf’s Cartridge Primer Size and Bullet Diameter Chart
NOTE: If you have the PDF reader installed in your browser, the Graf’s Chart may open in a new tab when you click on the image above. To save the three-page PDF file to your computer or device, click the Floppy Disc icon that appears in the lower right (after the PDF file opens). Here is the direct link: http://www.grafs.com/uploads/technical-resource-pdf-file/12.pdf.
Note: There are a few mistakes. If you are making 22 BR from Lapua brass, you’ll want a small rifle primer. Likewise with 25-20 WCF, you want a small primer.
Resource Tip from EdLongrange. We welcome reader submissions.
December 4th, 2014
Every year we anxiously await the new product announcement from Lapua. In 2014, Lapua brought out new bullets and new cartridge brass — .221 Fireball and .50 BMG. For 2015, Lapua once again brings out new brass offerings, this time three new flavors of cartridge brass, all made to Lapua’s exacting standards. First, Lapua will introduce factory 300 AAC Blackout (300 BLK) brass. This promises to take this highly-efficient, AR-friendly .30-caliber cartridge to another accuracy level. Second, Lapua will offer premium brass for the 7mm-08 cartridge, a very popular round among hunters and silhouette shooters. Lastly, in 2015, Lapua will produce 8x57mm JS brass. That’s good news for fans of this classic Mauser cartridge.
300 AAC Blackout Brass
Lapua’s Press release states: “Few cartridges have generated as much immediate interest as the 300 Blackout. Standardized by AAC, this diminutive cartridge is derived from the 223 Remington. Intended specifically for use in suppressed firearms, the versatility of the Blackout has appealed to a much broader range of shooters than just the audience for which it was originally designed. [Originally] intended to drive 220 grain bullets at subsonic velocities, the switch to lightweight bullets such as the 125 grain offerings delivers performance very similar to the venerable 7.62×39 cartridge. This makes the 300 Blackout potent enough for a wide range of shooting tasks, from certain tactical applications to many short range hunting situations involving medium-sized game. The ability for many 5.56mm/223 systems to be switched over to the 300 Blackout, merely by changing barrels, makes this an incredibly versatile combination. Lapua brings over nine decades of case manufacturing knowledge, precision and quality to the new Blackout, assuring the shooter of the very best performance.”
7mm-08 Remington Brass
 Lapua notes that it’s new 7mm-08 brass is made to very high standards, benefiting hunters as well as competitors: “The 7mm-08 came to dominate the High Power Silhouette rifle game shortly after its introduction, offering a superb combination of power, light recoil and accuracy. Since then, it has also been used to win National Championships in High Power competition, and become a staple for hunters as well. With ballistic performance exceeding that of the time honored 7x57mm Mauser, but suited to a shorter action, the 7mm-08 is an ideal cartridge for most big game hunting. Lapua brings… state-of-the-art manufacturing methods, combined with old world craftsmanship, to the production of these cases. Primer pockets and flash holes are held to strict tolerances to withstand repeated firings and reloadings. After final necking of the case, they are finished with the proper anneal [for] accuracy and durability.” Lapua also notes that it offers two new 7mm Scenar bullets, which will work very well in the new 7mm-08 cartridge brass.
8x57mm JS Brass
Last but not least, Lapua is producing 8x57mm JS brass. Lapua notes that: “When the 8x57mm JS cartridge was introduced in 1905, its innovative use of a high velocity and relatively light weight pointed bullet design revolutionized infantry combat. An outgrowth on the original 8x57J military round, the 8x57mm JS round served the German military in both world wars, and became a popular sporting cartridge in any area where there was a strong German influence. From African plains game to European stag and boar, the 8mm Mauser has earned an enviable reputation as a big game round in a wide array of conditions. Accurate, versatile and powerful, the 8x57mm JS still serves the sporting community well for a host of hunting applications. In answer to the requests of the many devotees of this fine cartridge, Lapua is pleased to announce our introduction of the new 8x57mmJS case. The new 8x57mmJS will deliver the same accurate, reliable performance for which Lapua cases are world renowned. This means tough, durable cases that will not only withstand repeated loadings, but retain their accuracy shot after shot. [Lapua’s 8x57mm JS brass offers] very tight tolerances in neck wall concentricity and overall uniformity.”
See Lapua’s New Products at SHOT Show 2015
If you plan to attend SHOT Show in Las Vegas, stop by and visit the Lapua Exhibit (booth #11929). With luck, samples of the new 7mm-08, 300 BLK, and 8×57 JS brass will be available to view. Lapua engineers will be on hand to talk about Lapua brass and bullets, and explain the production processes that make Lapua brass so durable and consistent. In recent years, in the world of centerfire competition, Lapua brass has absolutely dominated the winner’s circles as well as the record-books.
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