In discussions of ballistics, you’ll see references to “tangent”, “secant”, and “hybrid” bullet shapes. We know that, for many readers, these terms can be confusing. To add to the confusion, bullet makers don’t always identify their projectiles as secant or tangent designs. This article provides a basic explanation of tangent, secant, and hybrid ogive bullet designs, to help you understand the characteristics of these three basic bullet shapes.
Tangent vs. Secant vs. Hybrid
Most match bullets produced today use a tangent ogive profile, but the modern VLD-style bullets employ a secant profile. To further complicate matters, the latest generation of “Hybrid” projectiles from Berger Bullets feature a blended secant + tangent profile to combine the best qualities of both nose shapes. The secant section provides reduced drag, while the tangent section makes the bullet easier to tune, i.e. less sensitive to bullet seating depth position.
Berger Bullets ballistician Bryan Litz explains tangent and secant bullet ogive designs in a glossary section of his Applied Ballistics website, which we reprint below. Bryan then explains how tangent and secant profiles can be combined in a “hybrid” design.
How Bullet Ogive Curves are Defined
While the term “ogive” is often used to describe the particular point on the bullet where the curve reaches full bullet diameter, in fact the “ogive” properly refers to the entire curve of the bullet from the tip to the full-diameter straight section — the shank.
Understanding then, that the ogive is a curve, how is that curve described?
LITZ: The ogive of a bullet is usually characterized by the length of its radius. This radius is often given in calibers instead of inches. For example, an 8 ogive 6mm bullet has an ogive that is a segment of a circular arc with a radius of 8*.243 = 1.952”. A .30-caliber bullet with an 8 ogive will be proportionally the same as the 8 ogive 6mm bullet, but the actual radius will be 2.464” for the .30 caliber bullet.
For a given nose length, if an ogive is perfectly tangent, it will have a very specific radius. Any radius longer than that will cause the ogive to be secant. Secant ogives can range from very mild (short radius) to very aggressive (long radius). The drag of a secant ogive is minimized when its radius is twice as long as a tangent ogive radius. In other words, if a tangent ogive has an 8 caliber radius, then the longest practical secant ogive radius is 16 calibers long for a given nose length.”
Bryan Litz Explains Hybrid Design and Optimal Hybrid Seating Depths
Ogive Metrics and Rt/R Ratio
LITZ: There is a number that’s used to quantify how secant an ogive is. The metric is known as the Rt/R ratio and it’s the ratio of the tangent ogive radius to the actual ogive radius for a given bullet. In the above example, the 16 caliber ogive would have an Rt/R ratio of 0.5. The number 0.5 is therefore the lowest practical value for the Rt/R ratio, and represents the minimum drag ogive for a given length. An ogive that’s perfectly tangent will have an Rt/R ratio of 1.0. Most ogives are in between an Rt/R of 1.0 and 0.5. The dimensioned drawings at the end of my Applied Ballistics book provide the bullets ogive radius in calibers, as well as the Rt/R ratio. In short, the Rt/R ratio is simply a measure of how secant an ogive is. 1.0 is not secant at all, 0.5 is as secant as it gets.
Hybrid Bullet Design — Best of Both Worlds?
Bryan Litz has developed a number of modern “Hybrid” design bullets for Berger. The objective of Bryan’s design work has been to achieve a very low drag design that is also “not finicky”. Normal (non-hybrid) secant designs, such as the Berger 105gr VLD, deliver very impressive BC values, but the bullets can be sensitive to seating depth. Montana’s Tom Mousel has set world records with the Berger 105gr VLD in his 6mm Dasher, but he tells us “seating depth is critical to the best accuracy”. Tom says a mere .003″ seating depth change “makes a difference”. In an effort to produce more forgiving high-BC bullets, Bryan Litz developed the hybrid tangent/secant bullet shape.
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With days growing shorter and winter on its way — here’s a great audio “infotainment” resource to help fill those long winter nights. Leupold offers podcasts, 40-75 minutes in length, on a variety of topics of interest to hunters and precision shooters. A podcast is like a radio show that’s available 24/7, at your convenience. To “tune in” via your home computer or mobile devices, just visit the Leupold Podcast Page.
Oregon-based optics-maker Leupold & Stevens (“Leupold) offers the “Core Insider” podcast series. These podcasts deliver hunting advice and recount successful hunting trips — such as Caribou hunting in Alaska. Other Leupold podcasts provide optics info, industry intel, and tech tips. Leupold’s Core Insider podcasts can also be accessed directly from Leupold.com. From the Leupold Podcast Home Page, you can stream the podcasts live or download for later listening.
The Leupold Core Insider Podcasts cover a wide variety of shooting and hunting topics. One early episode features Leupold team members Kyle Lamb and Buck Doyle discussing long-range shooting, while recent Episode 55 explains how Binoculars and Rangefinders function. There are now 96 Leupold Podcasts available online for FREE.
Sherri Jo Gallagher, the second woman in history to win the NRA High Power National Championship, sports Eye Protection at Camp Perry. The first lady High Power Champion was Sherri’s mother, Nancy Tompkins.
In response to a Bulletin article about Protective Eyewear, one of our Canadian readers posted a personal story. His account demonstrates the importance of wearing eye protection whenever you shoot — no matter what type of firearm you are using — even air rifles. We hope all our readers take this to heart. All too often at rifle matches we see shooters, even some top competitors, risking their vision by failing to wear eye protection.
Eye and Hearing Protection are now MANDATORY for Highpower Rifle competitors and Pistol shooters in all CMP-affiliated matches. Starting in 2020 the CMP Highpower Rifle, Pistol, and CMP Games Rulebooks incorporated the following rule: “All competitors and competition officials are required to wear appropriate eye and hearing protection when on shooting range firing lines during highpower rifle or pistol firing. All competitors must comply with this requirement before they can participate in a CMP sponsored or sanctioned competition. Competitors are responsible for selecting their eyewear and hearing protection.”
Eye Protection — Lesson Learned by Nicholas from Canada
As a boy on a mixed farm on the plains the first shooting stick I owned was a Red Ryder BB gun. My Dad bought it for me as I showed a keen interest in the shooting and hunting sports. I was about 9 years old at the time.
We had literally thousands of sparrows in our large farm yard and they liked to roost on the steel railings in the barn loft. I took to slowly thinning out their ranks by flashlight at night as these little winged pests settled in the farm buildings.
One evening as I slayed sparrow after sparrow in the barn loft — with about a dozen farm cats following me to consume these easy meals, I fired at another bird centered in my flashlight beam.
However, my aim was a bit low — and the copper pellet hit the steel beam square on. Instantly I felt a sharp pain as the BB bounced back and hit me squarely between the eyes on the bridge of my nose – drawing blood from the partial penetration into the skin. A half inch either way and I’d have lost an eye!
Never, never, never shoot at any target with a steel background with any firearm, even a BB gun – is the hard lesson I learned, and wear the best shooting glasses that money can buy!
PLEASE REMEMBER THAT!!
Editor’s Comment: Among competitive pistol shooters, the use of safety eyewear is universal. You’ll never see Rob Leatham, Julie Golob, or Jerry Miculek competing without eye protection — for good reason. The handgun sports’ governing bodies effectively enforce mandatory eye protection policies. We wish the same could be said for competitive rifle shooting. We often see benchrest, High Power, and F-Class competitors shooting without eye protection. We’ve heard all the excuses, yet none of them trump the safety considerations involved.
We recommend that all shooters and hunters employ eye protection whenever they use firearms or are at a location where live fire is taking place. You only have two eyes. A tiny bullet fragment or ricochet is all it takes to cause permanent blindness in one or both eyes. As rifle shooters, we place our eyes a couple inches away from a combustion chamber operating at pressures up to 70,000 psi. I know quite a few guys who will religiously put on safety glasses when running a lathe or a drill press, yet the same guys won’t use eye protection when shooting their rifles — simply because it is “inconvenient”. That’s nuts. It doesn’t matter is you are a cub scout or a multi-time National Champion — you should wear eye protection.
I will give you a personal example. A year ago I was shooting a 9mm pistol. One of the cartridges had a primer burst outward blowing small particles, some brass, and a piece of the pistol’s extractor right back into my eyes. Thankfully I was wearing good wrap-around safety glasses. No injuries at all. But without those safety glasses, this could have been very serious. I always wear safety glasses with ALL firearms. Shown below is the same kind of primer blow-out I experienced, but with a .270 Win rifle cartridge.
Be wise — protect your eyes. To learn more about eyewear safety standards, and to learn about the latest options in ANSI Z87-certified protective eyewear, read our article on Eye Protection for Shooters.
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We created the above target a decade ago. Since then it has been used by tens of thousands of shooters. It has proven very popular as a load development target, since all your load data fits neatly in the boxes under each target. In fact this target is being employed by both rifle-makers and barrel-makers (including Criterion) to test their products. The target was designed for aiming efficiency. The diamonds have 1/2″ sides and you can align your cross-hairs on the horizontal and vertical lines. It is a clean design that is easy to see even at 200 yards with a 20X scope. When we test, we usually crank in a little elevation, setting the point-of-impact higher, so that our shots fall in the gray circles. That way you leave the squares intact for precise aiming.
We also use these two targets for load development and precision practice. The circle dot target can also be used for informal rimfire competition at 50 yards.
Right-Click Each Target to Download Printable PDFs.
How to Print Your Targets
Most of us have access to a printer at home or at work. That means you can print your own targets. You’ll find hundreds of free target designs online, including dozens of downloadable targets on our AccurateShooter.com Target Page. If you’re feeling creative, you can design your own target with a computer drawing program such as MS Paint.
Paper Stock Is Important
If you want your self-printed targets to show shots cleanly (and not rip when it gets windy), you should use quality paper stock. We recommend card stock — the kind of thick paper used for business cards. Card stock is available in both 65-lb and 110-lb weights in a variety of colors. We generally print black on white. But you might experiment with bright orange or yellow sheets. Forum Member ShootDots report: “They sell cardstock at Fed-Ex Kinko! I use either Orange or Yellow. That makes it easy to see the bullet holes clearly.” On some printers, with the heavier 110-lb card stock, you will need to have the paper exit through the rear for a straighter run.
Here are some Target-Printing Tips from our Forum members:
“Staples sells a 67-lb heavy stock that I have settled on. I use the light grey or light blue, either of these are easy on the eyes on bright days. I have used the 110-lb card stock as well and it works fine. It’s just a little easier to print the lighter stuff.” (JBarnwell)
“Cardstock, as mentioned, works great for showing bullet holes as it doesn’t tear or rip like the thin, lightweight 20-lb paper. I’ve never had a problem with cardstock feeding in the printer, just don’t stick too many sheets in there. If I need three targets, I load only three card stock sheets”. (MEMilanuk)
“20-lb bond works pretty well for me if I use a spray adhesive and stick the entire back of the paper’s surface to the backer board.” (Lapua40X)
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Do you know which one of your eyes is dominant? It’s easy to determine eye dominance with a simple exercise. Pick an object about 6-10 feet away (a light switch or door knob works well). Make an “OK” sign with your right hand (see photo) and hold that about 18″ from your face. Now, with both eyes open, look through the circle formed by your thumb and index finger. Center the circle on the object, so you can see the object in the middle.
Now, here’s the important part — while still holding your hand up, centered on the object, first close your right eye. If you don’t see the object anymore, then your right eye is dominant. If you still see the object, then repeat the procedure with the left eye shut and right eye open. If you don’t see the object when your left eye (only) is closed, then you are left-eye dominant.
The digital archives of Shooting Sports USA contain many interesting articles. A while back, Shooting Sports USA featured a “must-read” expert Symposium on Eye Dominance, as it affects both rifle and pistol shooting. No matter whether you have normal dominance (i.e. your dominant eye is on the same side as your dominant hand), or if you have cross-dominance, you’ll benefit by reading this excellent article. The physiology and science of eye dominance is explained by Dr. Norman Wong, a noted optometrist. In addition, expert advice is provided by champion shooters such as David Tubb, Lones Wigger, Dennis DeMille, Julie Golob, Jessie Harrison, and Phil Hemphill. NOTE: If the story doesn’t open at the links, go to the ssusa.org home page first, indicate you are over 18, and then CLICK HERE.
Top Rifle Champions Talk About Eye Dominance:
David Tubb — 11-Time National High Power Champion
I keep both eyes open, always. Some use an opaque blinder in rifle or shotgun shooting. If you close your non-dominant eye, you will not get as good a sight picture. If your aiming eye is not your dominant eye, you have even more of a problem to overcome.
Lones Wigger — World, National and Olympic Champion Rifleman
Shooters should try to use the dominant eye unless the vision is impaired and the non-dominant eye has better vision. You should always shoot with both eyes open since this will allow the shooting eye to function properly.
Dennis DeMille — National Service Rifle Champion
I close my non-shooting eye initially. Once I pick up my sight picture, it’s not something I focus on. For those that use a patch, I recommend that they use something white to block their view, rather than cover the eye.
Bruce Piatt — 2015 World Shooting Championship Winner
Some shooters, especially those with nearly equal or cross-dominance, will naturally find themselves squinting one eye. When anyone does this, you are also closing your dominant eye to some extent and adding stress to your face.
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Hand-loaders have never had so many great choices in single-stage presses, with many different configurations and features. There are classic O-Frame presses, Coax-style presses, Open-front presses, Pyramid presses, and compact C-Frame presses. Here is our 2019 Single Stage Press Showcase with products from Forster, Hornady, Lee, Lyman, MEC, and RCBS. We’ve included short videos showing the features of these reloading presses.
If you are shopping for a new press you should look at the various features of each. You may prefer something classic like a Rock Chucker, or the innovative open-front MEC. If you are looking for a compact press to use at the range, the Lyman C-Frame is very impressive for the price. And the Forster Co-Ax remains a great addition to any loading room.
MEC Marksman Single-Stage Press
If you are looking for a new, full-size single-stage reloading press, definitely consider the MEC Marksman. Created by the makers of the popular MEC shotshell reloading systems, the MEC Marksman combines a sturdy cast-iron frame with a modern open-front design. If you are looking for a new, full-size single-stage reloading press, definitely consider the MEC Marksman. Created by the makers of the popular MEC shotshell reloading systems, the MEC Marksman combines a sturdy cast-iron frame with a modern open-front design. With a $245.49 street price, the MEC Marksman press now costs more than an RCBS Rock Chucker Supreme press, but the MEC offers some distinct advantages — such as an open front plus a floating shell-holder system.
Our friend Gavin Gear of UltimateReloader.com got his hands on a MEC Marksman press and put it through its paces. He came away impressed with the product, saying it delivers excellent performance, and has many impressive features. Gavin tells us: “Cast iron tools and machines are a lifetime investment. The made-in-USA MEC Marksman features ductile cast-iron construction, an open-front frame design for easy cartridge access, a new floating shell-holder design with a unique retention system, and ambidextrous handle setup.” MEC also offers a wide selection of accessories for the Marksman press, including a press riser/mount, shell-holder caddy, and die trays.
Forster Co-Ax Press
If you are not yet familiar with the many unique features of the Forster Co-Ax, we recommend you watch the video above, a very thorough video review by Rex Roach. This shows how the press operates and highlights the design elements which set the Co-Ax apart from every other reloading press on the market. This 14-minute video shows the key Co-Ax features, explaining how the floating case-holder jaws work (3:30 time-mark), how the dies are held in place (4:40 time-mark), how spent primers are captured (6:10 time-mark), and how to set the primer seating depth (10:00 time-mark). We’ve used a Co-Ax for years and we still learned a few new things by watching this detailed video. If you are considering purchasing a Co-Ax, definitely watch this video start to finish.
In recent years, Forster Co-Ax® presses have been somewhat hard to find, as demand has out-stripped supply. The Co-Ax has many dedicated fans, given its unique features, such as the floating case-holder jaws, and easy, rapid slide-in/slide-out die placement. We’ve also found that Co-Ax presses load very straight ammo and we like the ability to switch between short handle (good for bullet seating) and long handle (ideal for heavy case-sizing tasks). We also think the Forster Co-Ax has one of the best spent primer capture systems on the market — a straight drop into a removable plastic cup. Simple and it works.
Lyman Brass Smith Victory Single-Stage Press
Lyman’s sturdy Victory Single-stage Press is a full-size unit that competes with the RCBS Rock Chucker Press. With beefy cast iron construction, the Victory’s strength and leverage rivals the Rock Chucker. The press operates smoothly and the handle can be mounted on either side.
If you like to prime cases using a press, this Victory press has a priming system that’s much easier to use than the RCBS Rock Chucker system. The priming tube is right up front, with multiple primers loaded vertically in a tube. Simply push the shuttle at the button of the tube to advance the primer into place.
For convenience, the entire primer-loading system can also be removed so it doesn’t interfere with case and bullet-handling operations. We generally prefer to prime cases separately using a dedicated hand- or bench-mounted tool, but the Victory press does the job nicely.
Overall, the Victory is a great value in a full-size “O-Frame” press with sturdy construction and a solid Lyman warranty. It is available now for $208.52 on Amazon.
RCBS Rock Chucker Supreme Single-Stage Press
Nearly every serious hand-loader has owned or used the RCBS Rock Chucker press. This Editor still uses a Rock Chucker passed down by his brother 20 years ago. And yes, it is still going strong. The latest Rock Chucker Supreme single-stage press features an improved “upside-down Y-path” dual-bin spent primer catcher. Otherwise the Rock Chucker Supreme remains big, strong, versatile and sturdy. It has very strong linkages, with a compound leverage system providing plenty of power — FL-sizing is a breeze even with large, magnum cases. The 1″-diameter ram has 12.5 sq. inches of ram-bearing surface.
Some people may not know that the Rock Chucker offers a secondary 1 1/4″ x 12 thread for shotshell reloading dies and Piggyback 3 upgrade. The Rock Chucker Supreme retails for $213.79 now at Powder Valley and qualifies for a $35 RCBS rebate, lowering your net cost to $178.79 (after rebate). The RCBS Rock Chucker is definitely a quality product that can last a lifetime. For heavy-duty sizing chores this remains one of the best choices in single-stage presses. This is a good time to buy a RCBS press with the current RCBS Rebate Program.
Lyman Brass Smith Ideal C-Frame Compact Press
The Lyman Brass Smith Ideal Press is a very affordable, cast iron C-Frame reloading press. We think it is the new “class leader” in compact presses. This works great as a secondary press for your reloading room or a small press you can take to the range. The large front opening allows you to access the shell holder without hitting the support bar on other types of presses. Unlike other compact presses made from aluminum, Lyman’s Ideal press is cast iron so it is rigid and strong. The high-quality steel ram is one inch in diameter. The Brass Smith is a true ambidextrous press that can be accessed from either side and mounted the same. This is a great choice for a second, auxiliary press for depriming and bullet seating. It is now just $119.66 at Precision Reloading.
Hornady Iron Single Stage (Open-front) Press
In this “Reloading with Rosie” video, the attractive female host loads some ammo using the Hornady Iron Press. With a beefy, pyramid-style cast-iron frame with an open front, this press offers some advantages over a traditional “O-Frame” type press. Access is considerably easier, for one thing. And the top of the press includes slots to hold dies and tools — that’s really a very nice feature that saves time. Also an optional “automatic” priming system shuttles primers from a vertical tube in the back to the shell-holder in the front. That’s clever. Over all the Iron Press is a nice piece of engineering — good job Hornady. It is offered for $314.78 at Precision Reloading.
Lee Classic Cast (Iron) Breech Lock Press
The Lee Classic Cast Breech Lock Press offers excellent value for the money ($190.99 at Midsouth). Based on the proven design of the Classic Cast press, the updated Breech Lock series adds the quick-change die bushing and an improved primer drop system. This press is strong, with cast iron frame, all-steel linkage, and 12 square inches of ram bearing surface.
Lee says this press has the “largest opening and the longest stroke in the industry” among O-frame type presses. The handle can be mounted on either side. We love the fact that the handle ANGLE can be adjusted, as well as the lever arm length — that allows you to adjust travel and leverage to suit your preference. Smart engineering.
The new spent primer drop features a large-diameter hollow ram with clear hose that drops primers straight to a bin — that’s simple and effective. The press is very rigid and the base is wide enough for good stability. We have one of these Classic Cast Breech Lock Presses in our reloading room and it works well.
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This article comes from the Criterion Barrels website. It provides good, conservative advice about barrel cleaning. Understand that cleaning methods may need to be adapted to fit the amount and type of fouling (and the particular barrel). In general, we do try to minimize brushing, and we follow the procedures Criterion recommends respecting the crown/muzzle. We have also had very good success using wet patches followed by Wipe-Out bore foam. Along with the practices outlined by Criterion below, you may want to try Wipe-Out foam. Just be sure to use a fitted cleaning rod bore guide, to keep foam out of the action recesses and trigger assembly.
The above video shows how to apply Wipe-Out or other bore-cleaning foam. We use a slightly different method. First, we use 3-4 wet patches to remove loose carbon fouling. Then we apply the foam as shown, but usually from the muzzle end (with bore guide in chamber). Here’s the important point — after 20-30 minutes, once the bubbles have dissipated, we apply the foam a second time, getting more of the active ingredients into the barrel. We then patch out, as shown, after 3-4 hours.
What is the Best Way to Clean a Rifle Barrel?
We are asked this question quite frequently alongside requests for recommended break-in procedures. Improper barrel cleaning methods can damage or destroy a barrel, leading to diminished accuracy or even cause a catastrophic failure. When it comes to barrel maintenance, there are a number of useful techniques that we have not listed. Some techniques may work better with different barrel types. This series of recommendations is designed to incorporate a number of methods that the Criterion Barrels staff has used successfully both in the shop and on their personal rifles. Please feel free to to list your own recommendations in the below comments section.
We recommend the use of the following components during rifle cleaning:
• Cloth patches (sized for the appropriate caliber)
• Brass jag sized properly for your bore [Aluminum and Nylon Jags also work]
• One-piece coated cleaning rod
• General bore cleaner/solvent (Example: Hoppes #9)
• Copper solvent of your choosing (Example: Sweets/KG 12)
• Fitted cleaning rod bore guide
• Plastic AP brush or toothbrush
• Q-Tips
• Plastic dental picks
• CLP or rust preventative type cleaner
There are a number of schools of thought relating to the frequency in which a barrel should be cleaned. At minimum we recommend cleaning a barrel after each shooting session to remove condensation, copper, and carbon build-up. Condensation is the greatest immediate threat, as it can cause the barrel to rust while the rifle sits in storage. Copper and carbon build-up may negatively impact future barrel performance, increasing the possibility of a failure in feed or function. Fouling should be removed whenever possible.
The below tips will help limit the wear of different parts of your barrel during routine maintenance, helping extend the life of the barrel and improving its performance.
The Lands and Grooves
This portion of the barrel may experience reduced efficiency due to copper fouling and cleaning rod damage. If copper fouling takes place during the initial break-in of the rifle, make sure to check our barrel break-in article.
For regular maintenance we suggest using a single piece coated cleaning rod rather than the traditional segmented rod or bore snake. While segmented rods and bore snakes may be convenient for field use, the corners between the segments may bow out and catch on the lands, scraping along the length of the rifling. Residual grit and particles from expended cartridges may also get caught between segments, resulting in an abrasive surface working its way down the length of the barrel. Most bore snakes will remove significant amounts of carbon fouling, but may fall short in the removal residual carbon buildup and copper fouling during deep cleaning. Good rods can be sourced from multiple manufacturers, but we have found good results using both Pro-Shot and Dewey brand products.
General cleaning requires the use of patches rather than nylon or brass bore brushes. Brass brushes may be required when aggressive cleaning is required, but can lead to unnecessary wear on the barrel if used frequently. This is not due to the nature of the soft brushes themselves, but from the abrasive particles of grit that become embedded in the material that is being run repeatedly through the bore. We recommend the use of bore guides when cleaning from both the muzzle and breech. These bore guides will help serve to protect the crown and throat from cleaning rod damage.
If significant resistance develops while running the cleaning rod through the bore, no attempt should be made to force it in further. Back the rod out and inspect the barrel to determine the cause of the resistance. The jag may be pushing between a bore obstruction and the rifling, digging a divot into the barrel before pushing the obstruction back through the muzzle. One way to minimize the risk of a stuck rod is by utilizing a slightly smaller patch during the initial push.
The process of cleaning the length of the rifling is relatively straightforward:
1. Check to make sure the rifle is safely unloaded.
2. Carry out any necessary disassembly procedures prior to cleaning.
3. Remove bolt (if possible) and insert fitted cleaning rod bore guide in action.
4. Soak a patch in bore solvent (similar to Hoppes #9).
5. Center and affix the patch on the brass jag, inserting it into the chamber end of the barrel. A misaligned patch may cause the jag to damage the lands of the rifling, so make sure the patch is centered on the jag. [Note, an aluminum or nylon jag will not show a “false positive”.]
6. Run the patch the full length of the barrel, retracting it upon reaching the end of the muzzle.
7. Let the solvent sit for a minute.
8. Continue to run patches through the bore until carbon residue is minimized.
9. Run a dry patch through the bore to ensure carbon residue has been removed.
10. Soak a patch in copper solvent (Sweet’s or KG-12).
11. Run the patch through the bore, leaving it to sit for 3-5 minutes (do not let solvent sit for more than 15 minutes.*)
12. Repeat this process until no blue residue remains on the patches.
13. Run a patch of Hoppes #9 and a dry patch through the bore to neutralize the copper solvent.
14. Inspect the barrel prior to reassembling the rifle, verifying that no bore obstructions remain.
*Please note that some ammonia-based copper solvents may prove to be corrosive if left sitting in the barrel for an extended period of time. It is essential that these solvents be removed within 15 minutes to avoid ruining the bore.
The Crown
The crown is the portion of the barrel where the bullet loses contact with the lands and grooves and proceeds to exit the firearm. The area most critical to accuracy potential is the angle where the bullet last touches the bore of the barrel.
Avoid damage to this area by using a plastic toothbrush and CLP type cleaner to scrub the crown from the exterior of the barrel. Even the most minimal variation in wear to the crown will negatively impact barrel performance, so be careful to avoid nicking or wearing away this part of the barrel.
The 30 BR is an amazing little cartridge. However, 30 BR shooters do have to neck-up 6mmBR or 7mmBR brass and then deal with some issues that can arise from the expansion process. One of our Forum members was concerned about the donut that can form at the new (expanded) neck-shoulder junction. Respected bullet-maker Randy Robinett offers tips on how to deal with the “dreaded donut”.
The Forum member was concerned about thinning the brass if he turned his 30 BR necks after expansion: “Everything I have found on 30 BR case-forming says to simply turn off the bulge at the base of the neck caused by the old 6BR shoulder. I expanded my first case and measured the neck at 0.329″ except on the donut, where it measures 0.335″. Looking inside the case… reveals a groove inside the case under the donut. Now, it is a fact that when I turn that neck and remove the donut, the groove is still going to be there on the inside? That means there is now a thin-spot ring at the base of the neck that is .005 thinner than the rest of the neck. Has anyone experienced a neck cracking on this ring?”
Randy Robinett, who runs BIB Bullet Co., is one of the “founding fathers” of the 30 BR who help prove and popularize the 30 BR for benchrest score shooting. Randy offers this advice on 30 BR case-forming:
While the thinner neck-base was one of our original concerns, unless one cuts too deeply INTO the shoulder, it is not a problem. For my original 30BR chamber, thirty (30) cases were used to fire 6,400 rounds through the barrel. The cases were never annealed, yet there were ZERO case failures, neck separations, or splits. The case-necks were turned for a loaded-round neck diameter of .328″, and, from the beginning, sized with a .324″ neck-bushing.
The best method for avoiding the ‘bulge’ is to fire-form prior to neck-turning (several methods are successfully employed). Cutting too deeply into the shoulder can result in case-neck separations. I have witnessed this, but, with several barrels and thousands to shots fired, have not [personally] experienced it. The last registered BR event fired using that original barrel produced a 500-27x score and a second-place finish. [That’s] not bad for 6K plus shots, at something over 200 firings per case.
Check Out the 30 BR Cartridge Guide on AccurateShooter.com
You’ll find more information on 30 BR Case-forming in our 30 BR Cartridge Guide. Here’s a short excerpt from that page — some tips provided by benchrest for score and HBR shooter Al Nyhus:
30 BR Case-Forming Procedure by Al Nyhus
The 30 BR cartridge is formed by necking-up 6mmBR or 7mmBR brass. You can do this in multiple stages or in one pass. You can use either an expander mandrel (like Joe Entrekin does), or a tapered button in a regular dies. Personally, I use a Redding tapered expander button, part number 16307. This expands the necks from 6mm to .30 cal in one pass. It works well as long as you lube the mandrel and the inside of the necks. I’ve also used the Sinclair expander body with a succession of larger mandrels, but this is a lot more work and the necks stay straighter with the Redding tapered button. This button can be used in any Redding die that has a large enough inside diameter to accept the BR case without any case-to-die contact.
Don’t be concerned about how straight the necks are before firing them the first time. When you whap them with around 50,000 psi, they will straighten out just fine! I recommend not seating the bullets into the lands for the first firing, provided there is an adequate light crush-fit of the case in the chamber. The Lapua cases will shorten from approx. 1.550″ to around 1.520″ after being necked up to 30-caliber I trim to 1.500″ with the (suggested) 1.520 length chambers. I don’t deburr the flash holes or uniform the primer pockets until after the first firing. I use a Ron Hoehn flash hole deburring tool that indexes on the primer pocket, not through the case mouth. — Al Nyhus
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Here’s a November video bonus for our Daily Bulletin readers. Today we showcase three of the most amazing 3D “cutaway” gun animations ever created. Watch the operations of a pump shotgun, bolt-action rifle, and semi-automatic pistol. The superb cutaway views show details of the firearms’ internal parts, and show how ammunition cycles start to finish. Each of these videos took hundreds of man-hours to create, and each has been watched many millions of times.
Remington 870 Pump-Action Shotgun
This 3D animation shows how a Remington 870 pump-action shotgun works. The animation is superbly done, showing every aspect of the internal operation. Folks, if you have any interest in shotguns you should definitely watch this video start to finish. This shotgun video has received 3.9 million views in just 10 days!
The video’s talented creator, Matt Rittman states: “Cinema 4D was used to create each individual part, as well as animating everything. Substance Painter was used to create the wood stock and fore-end textures. Corona renderer was used for final output of lighting and textures.” See more of Matt’s 3D videos on his popular YouTube Channel.
This 3D animation showing how a Mauser Karabiner 98K (KAR 98K) bolt-action rifle works. The Karabiner 98K is a controlled-feed bolt-action rifle based on the famous Mauser M98 system. Video creator Matt Rittman notes: “Cinema 4D was used to create each individual part, as well as animating everything. Substance Painter was used to create the wood stock texture. Corona renderer was used to render everything. This animation took me over 500 hours to create.” This video has been watched over 21 million times!
Every bolt-action rifle owner should watch this remarkable video. It shows key processes which are common to many actions — Cocking the Bolt, Feeding from magazine, Engagement of Bolt Lugs, Activation of Trigger and Movement of Firing Pin, and Extraction with Ejection. The modeling of the inside of the bolt and fire-control group is excellent. This really is a superb video that will help rifle owners understand what happening inside their guns as the bolt is cycled. See more of Matt’s 3D videos on his popular YouTube Channel.
This 3D animation demonstrates how a modern semi-automatic, double-action-only Glock 19 handgun works. Cinema 4D was used to create each individual part, as well as animating everything. Substance Painter was used to create the main textures. Corona renderer was used to render everything. This animation took me over 500 hours to create. one of the most-watched gun videos ever created, this Glock 19 animation has been viewed over 78.6 MILLION times!
Video Highlights for Glock 19 Pistol
0:00 Intro
0:11 Basic Function
0:39 Case Extraction
0:47 Cartridge Loading
1:02 Trigger Reset
About Matt Rittman, the 3D Animator/Artist These three amazing videos were all created by the gifted computer graphics artist Matt Rittman. On his Matt Rittman YouTube Channel, Matt states: “I’m a 3D Generalist/Motion Designer from Des Moines, Iowa. I have always enjoyed animation and illustrating how things work. I’m especially interested in cars and anything mechanical.
My aim for this channel is to provide easy to understand how-it-works 3D animations. I will occasionally be releasing tutorials centered around Cinema 4D and the different capabilities of the software.”
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When he measures his loads or sorts bullets by weight, Forum Member Boyd Allen often employs his trusty RCBS 10-10 balance beam scale (although he does have handy digital scales as well). He finds that the balance beam scale works predictably, time after time, and it doesn’t suffer from the drift and calibration issues that plague some of the less expensive electronic scales on the market.
To make it easier to see the balance point, Boyd has adapted a magnifying glass with a mirror. This makes the end of his balance beam easier to view from his normal position on the bench. Boyd explains: “This set-up uses a cheap magnifier with positioning arms that was probably designed to hold and magnify small objects while soldering them. I think that it came from Harbor Freight many years ago. The mirror lets you look at the scale as if is was at eye level, and of course the magnifier makes the image easier to see.”
If you have a balance beam scale, we suggest you try this simple enhancement. We predict you’ll find the magnifier speeds up the process with enhanced assurance of your load weight.
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For many years, the U.S. Army Marksmanship Unit (USAMU) regularly published reloading “how-to” articles on the USAMU Facebook page. In this article, the USAMU’s reloading gurus address a question frequently asked by prospective handloaders: “Should I buy a single-stage press, or a progressive?” The USAMU says the best answer is Solomon-esque in both its wisdom and simplicity: “Get BOTH!” However, there is definitely more to the issue, as the USAMU explains below.
Progressive Press Safety Considerations
by USAMU Staff
Many are the beginning handloaders who have asked a friend about their “setting up” a progressive press for them. The idea is that the newbie could then just feed in components and crank out buckets of practice ammo without needing to really learn much about handloading. Tempting though this might be, that’s simply not how it works. Such an approach might be ok if there were never a malfunction with either press or operator, but that’s unrealistic. Our hypothetical newbie would then lack the knowledge to problem-solve most situations.
Worse yet, several different handloading operations would be occurring at different stations on the progressive press at the same time. It takes an experienced operator to keep track of, and truly understand the significance of, all those potential mini-problems. Loading without this experience is a recipe for potential disaster – such as a double powder charge (especially with pistol cartridges) dropped while the loader was attending to some other function, etc. Progressives are an animal unto themselves, and while they offer many benefits, they do take some getting used to – even by experienced handloaders!
ILLUSTRATIVE HORROR STORY
Here, enter a 40-year veteran handloader who decided to jump onto the progressive bandwagon late in his career, having used only single-stage presses all his life. A High Master NRA High Power Rifle competitor, he had no background in competitive pistol shooting, where historically most progressive presses are found.
Experienced Action Pistol shooters have typically encountered multiple episodes in which shooters “skipped” a powder charge for some reason, leading to a squib round and a bullet possibly lodged in the bore. Thus, at matches, it’s reflexive for them to yell “STOP!” in unison if they see a shooter get a “click” vs. a “bang”, and rack the slide to keep firing. This writer has personally seen several pistols saved in just such scenarios over the years.
Click No Bang — What NOT to Do
Our High Master set up a popular progressive press and began turning out .223 Rem 100-yard practice ammo with abandon. He was using a moly-coated 52gr match bullet and an economical, fast-burning surplus powder that gave great accuracy. Once on the range, he began practicing strings of rapid-fire. All was well, until he heard “Click!” rather than “Boom”.
Lacking the above experience or onlookers to halt him, he reflexively operated the charging handle on his expensive, custom NM AR15 Service Rifle, and the next trigger squeeze reportedly registered on seismographs over at least a three-state radius. He sat, uninjured but bewildered, until the hail of expensive bits and pieces quit raining down around him.
When the smoke cleared, he immediately cursed the horrid, evil, demonically-possessed progressive press for this, his first-ever reloading mishap. His $1400 NM upper was ruined, but thankfully, his $800 pre-ban lower… and he had escaped injury.
This tale is told not to discourage the use of progressive presses, but to emphasize the need to EASILY and IMMEDIATELY KNOW what is happening with the press at each station, every time the handle is cranked. Not to do so is, as they say, “bad ju-ju.”
It illustrates why we at the USAMU Handloading Shop agree in recommending that new handloaders should begin with a single-stage press. Once one thoroughly learns the steps in each phase of handloading by repeated experience, then one will be qualified to move on to a progressive press.
The single-stage press will REMAIN virtually indispensable for one’s entire handloading career, even after having purchased a progressive press (or two). There are endless small projects that are best handled on a single-stage press, and a poll of USAMU’s Handloading staff reveals that not one would willingly be without his single-stage press, despite owning at least one progressive.
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Sinclair Internationalhas released an interesting article about Case Concentricity* and bullet “run-out”. This instructional article by Bob Kohl explains the reasons brass can exhibit poor concentricity, and why high bullet run-out can be detrimental to accuracy.
Concentricity, Bullet Alignment, and Accuracyby Bob Kohl
The purpose of loading your own ammo is to minimize all the variables that can affect accuracy and can be controlled with proper and conscientious handloading. Concentricity and bullet run-out are important when you’re loading for accuracy. Ideally, it’s important to strive to make each round the same as the one before it and the one after it. It’s a simple issue of uniformity.
The reason shooters work with tools and gauges to measure and control concentricity is simple: to make sure the bullet starts down the bore consistently in line with the bore. If the case isn’t properly concentric and the bullet isn’t properly aligned down the center of the bore, the bullet will enter the rifling inconsistently. While the bore might force the bullet to align itself with the bore (but normally it doesn’t), the bullet may be damaged or overstressed in the process – if it even it corrects itself in transit. These are issues we strive to remedy by handloading, to maintain the best standard possible for accurate ammunition.
The term “concentricity” is derived from “concentric circle”. In simple terms it’s the issue of having the outside of the cartridge in a concentric circle around the center. That goes from case head and center of the flash hole, to the tip of the bullet.
Factors Affecting Concentricity
The point of using this term is to identify a series of issues that affect accurate ammunition. Ideally this would work best with a straight-walled case; but since most rifle cartridge cases are tapered, it equates to the smallest cross section that can be measured point by point to verify the concentric circle around the center. For the examples below, I’m working with .308 Winchester ammo.
Figure 1: The cartridge.
Figure 2: Centerline axis of the case, extending from flash hole to case mouth.
The case walls have to be in perfect alignment with the center, or axis, of that case, even if it’s measured at a thousandth of an inch per segment (in a tapered case).
Figure 3: Case body in alignment with its axis, or centerline, even in a tapered case.
The case neck must also be in alignment with its axis. By not doing so you can have erratic bullet entry into the bore. The case neck wall itself should be as uniform as possible in alignment and in thickness (see the M80 7.62x51mm NATO cartridge in Figure 5) and brass can change its alignment and shape. It’s why we expand the case neck or while some folks ream the inside of the neck and then turn the outside for consistent thickness, which affects the tension on the bullet when seated.
Figure 4: Neck in alignment with center of the case axis.
Figure 5: Variations in case neck wall thickness, especially on some military brass, can cause an offset of the bullet in its alignment. This is an M80 ball round. Note the distinct difference of the neck walls.
Having a ball micrometer on hand helps, especially with military brass like 7.62x51mm in a semi-auto rifle, where there are limits as to how thin you want the neck walls to be. In the case of 7.62 ball brass you want to keep the wall to .0145″.
Figure 6: A ball micrometer like this RCBS tool (#100-010-268) can measure case neck thickness.
Turning the outside of the neck wall is important with .308 military cases regardless of whether you expand or ream the neck walls. There are several outside neck turning tools from Forster, Hornady, Sinclair, and others. I’ve been using classic Forster case trimming (#100-203-301) and neck turning (#749-012-890) tools for 40 years.
Bullet Run-Out
The cartridge, after being loaded, still needs to be in alignment with the center of the case axis. Figure 7 shows a bad example of this, a round of M80 ball. A tilted bullet is measured for what’s known as bullet “run-out”.
Figure 7: An M80 round with the bullet tilted and not aligned with the axis. This will be a flyer!
Run-out can be affected by several things: (1) improperly indexing your case while sizing, which includes not using the proper shell holder, especially while using a normal expander ball on the sizing die (it also can stretch the brass). (2) The head of a turret press can flex; and (3) improper or sloppy bullet seating. This is also relevant when it comes to using a progressive press when trying to load accuracy ammo.
Mid Tompkins came up with a simple solution for better bullet seating years ago. Seat your bullet half way into the case, back off the seater die and rotate the case 180 degrees before you finish seating the bullet. It cuts down on run-out problems, especially with military brass. You also want to gently ream the inside of the neck mouth to keep from having any brass mar the surface of the bullet jacket and make proper seating easier. A tilted bullet often means a flyer.
Figure 8: Proper alignment from the center of the case head to the tip of the bullet.
(NOTE: This links to a Web Archive version of the original Sinclair Int’l article.)
*Actually some folks would say that if we are talking about things being off-center or out-of-round, we are actually talking about “eccentricity”. But the tools we use are called “Concentricity Gauges” and Concentricity is the term most commonly used when discussing this subject.
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Hybrid Bullet Design — Best of Both Worlds?
In response to a Bulletin article about 
Eye Protection — Lesson Learned
Editor’s Comment: Among competitive pistol shooters, the use of safety eyewear is universal. You’ll never see Rob Leatham, Julie Golob, or Jerry Miculek competing without eye protection — for good reason. The handgun sports’ governing bodies effectively enforce mandatory eye protection policies. We wish the same could be said for competitive rifle shooting. We often see benchrest, High Power, and F-Class competitors shooting without eye protection. We’ve heard all the excuses, yet none of them trump the safety considerations involved.
How to Print Your Targets
Do you know which one of your eyes is dominant? It’s easy to determine eye dominance with a simple exercise. Pick an object about 6-10 feet away (a light switch or door knob works well). Make an “OK” sign with your right hand (see photo) and hold that about 18″ from your face. Now, with both eyes open, look through the circle formed by your thumb and index finger. Center the circle on the object, so you can see the object in the middle.
If you are not yet familiar with the many unique features of the Forster Co-Ax, we recommend you watch the video above, a very thorough video review by Rex Roach. This shows how the press operates and highlights the design elements which set the Co-Ax apart from every other reloading press on the market. This 14-minute video shows the key Co-Ax features, explaining how the floating case-holder jaws work (3:30 time-mark), how the dies are held in place (4:40 time-mark), how spent primers are captured (6:10 time-mark), and how to set the primer seating depth (10:00 time-mark). We’ve used a Co-Ax for years and we still learned a few new things by watching this detailed video. If you are considering purchasing a Co-Ax, definitely watch this video start to finish.
Lyman’s sturdy Victory Single-stage Press is a full-size unit that competes with the RCBS Rock Chucker Press. With beefy cast iron construction, the Victory’s strength and leverage rivals the Rock Chucker. The press operates smoothly and the handle can be mounted on either side.
Nearly every serious hand-loader has owned or used the RCBS Rock Chucker press. This Editor still uses a Rock Chucker passed down by his brother 20 years ago. And yes, it is still going strong. The latest Rock Chucker Supreme single-stage press features an improved “upside-down Y-path” dual-bin spent primer catcher. Otherwise the Rock Chucker Supreme remains big, strong, versatile and sturdy. It has very strong linkages, with a compound leverage system providing plenty of power — FL-sizing is a breeze even with large, magnum cases. The 1″-diameter ram has 12.5 sq. inches of ram-bearing surface.
The Lee Classic Cast Breech Lock Press offers excellent value for the money (
The 30 BR is an amazing little cartridge. However, 30 BR shooters do have to neck-up 6mmBR or 7mmBR brass and then deal with some issues that can arise from the expansion process. One of our Forum members was concerned about the donut that can form at the new (expanded) neck-shoulder junction. Respected bullet-maker Randy Robinett offers tips on how to deal with the “dreaded donut”.
These three amazing videos were all created by the gifted computer graphics artist Matt Rittman. On his 
