Photo 1: Three Near-Equal-Weight 7mm Bullets with Different Shapes
TECH TIP: Bullets of the same weight (and caliber) can generate very different pressure levels due to variances in Bearing Surface Length (BSL).
Bullet 1 (L-R), the RN/FB, has a very slight taper and only reaches its full diameter (0.284″) very near the cannelure. This taper is often seen on similar bullets — it helps reduce pressures with good accuracy. The calculated BSL of Bullet 1 was ~0.324″. The BSL of Bullet 2, in the center, was ~0.430”, and Bullet 3’s was ~ 0.463″. Obviously, bullets can be visually deceiving as to BSL!
This article from the USAMU covers an important safety issue — why you should never assume that a “book” load for a particular bullet will be safe with an equal-weight bullet of different shape/design. The shape and bearing surface of the bullet will affect the pressure generated inside the barrel. This is part of the USAMU’s Handloading Hump Day series, publiches on the USAMU Facebook page.
Beginning Handloading, Part 13:
Extrapolating Beyond Your Data, or … “I Don’t Know, What I Don’t Know!”
We continue our Handloading Safety theme, focusing on not inadvertently exceeding the boundaries of known, safe data. Bullet manufacturers’ loading manuals often display three, four, or more similar-weight bullets grouped together with one set of load recipes. The manufacturer has tested these bullets and developed safe data for that group. However, seeing data in this format can tempt loaders — especially new ones — to think that ALL bullets of a given weight and caliber can interchangeably use the same load data. Actually, not so much.
The researchers ensure their data is safe with the bullet yielding the highest pressure. Thus, all others in that group should produce equal or less pressure, and they are safe using this data.
However, bullet designs include many variables such as different bearing surface lengths, hardness, and even slight variations in diameter. These can occasionally range up to 0.001″ by design. Thus, choosing untested bullets of the same weight and caliber, and using them with data not developed for them can yield excess pressures.
This is only one of the countless reasons not to begin at or very near the highest pressure loads during load development. Always begin at the starting load and look for pressure signs as one increases powder charges.
Bullet bearing surface length (BSL) is often overlooked when considering maximum safe powder charges and pressures. In photo 1 (at top), note the differences in the bullets’ appearance. All three are 7mm, and their maximum weight difference is just five grains. Yet, the traditional round nose, flat base design on the left appears to have much more BSL than the sleeker match bullets. All things being equal, based on appearance, the RN/FB bullet seems likely to reach maximum pressure with significantly less powder than the other two designs.
Bearing Surface Measurement Considerations
Some might be tempted to use a bullet ogive comparator (or two) to measure bullets’ true BSL for comparison’s sake. Unfortunately, comparators don’t typically measure maximum bullet diameter and this approach can be deceiving.
Photo 2: The Perils of Measuring Bearing Surface Length with Comparators
In Photo 2, two 7mm comparators have been installed on a dial caliper in an attempt to measure BSL. Using this approach, the BSLs differed sharply from the original [measurements]. The comparator-measured Bullet 1 BSL was 0.694” vs. 0.324” (original), Bullet 2 was 0.601” (comparator) vs. 0.430” (original), and Bullet 3 (shown in Photo 2) was 0.602” (comparator) vs. 0.463” (original). [Editor’s comment — Note the very large difference for Bullet 1, masking the fact that the true full diameter on this bullet starts very far back.]
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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.
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Since Sierra introduced the Tipped MatchKing® (TMK®) line of bullets in 2015, we have had a few questions from customers regarding the two lines of bullets (MK vs TMK). Some shooters are concerned that the tried-and-true MatchKing® bullets will be replaced with the Tipped MatchKing® bullets. For those of you worried, relax, the old standby MatchKings® that you have shot for years are here to stay, and we will happily continue to make them for you.
For those that like to try new products, we are planning on both continuing and expanding the Tipped MatchKing® line. Even where there are two bullets within these two lines that have matching weights (pictured above), 22 caliber 69 and 77 grain, 6mm 95 gr, 30 caliber 125, 155, 168 and 175 grains, we are not going to replace the MatchKings® with the Tipped MatchKing®. We are, however, going to continue to offer both lines of bullets for your use and enjoyment. Keep an eye out for new additions to our product line!
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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.
There is nothing more frustrating (or embarassing) than sending a live round into your expensive new chronograph. As the photo below demonstrates, with most types of chronographs (other than the barrel-hung Magnetospeed), you can fatally injure your expensive chrono if it is not positioned precisely.
When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).
Adjust the height, angle and horizontal position of the chronograph so the bullet will pass through the middle of the “V” below the plastic diffusers, no less than 5″ above the light sensors. We put tape on the front sky-screen supports to make it easier to determine the right height over the light sensors.
Use a Test Backer to Confirm Your Bullet Trajectory
You can put tape on the support rods about 6″ up from the unit. This helps you judge the correct vertical height when setting up your rifle on the bags. Another trick is to hang a sheet of paper from the rear skyscreen and then use a laser boresighter to shine a dot on the paper (with the gun planted steady front and rear). This should give you a good idea (within an inch or so) of the bullet’s actual flight path through the “V” over the light sensors. Of course, when using a laser, never look directly at the laser! Instead shine the laser away from you and see where it appears on the paper.
Alignment of Chronograph Housing
Make sure the chrono housing is parallel to the path of the bullet. Don’t worry if the unit is not parallel to the ground surface. What you want is the bullet to pass over both front and rear sensors at the same height. Don’t try to set the chrono height in reference to the lens of your scope–as it sits 1″ to 2″ above your bore axis. To avoid muzzle blast interference, set your chronograph at least 10 feet from the end of the muzzle (or the distance recommended by the manufacturer).
Rifles with Elevated Iron Sights
All too often rookie AR15 shooters forget that AR sights are positioned roughly 2.4″ above the bore axis (at the top of the front sight blade). If you set your bullet pass-through point using your AR’s front sight, the bullet will actually be traveling 2.4″ lower as it goes through the chrono. That’s why we recommend bore-sighting and setting the bullet travel point about 5-8″ above the base of the sky-screen support shafts. (Or the vertical distance the chronograph maker otherwise recommends). NOTE: You can make the same mistake on a scoped rifle if the scope is set on very tall rings, so the center of the cross-hairs is much higher than the bore axis line.
TARGET AIM POINT: When doing chrono work, we suggest you shoot at a single aiming point no more than 2″ in diameter (on your target paper). Use that aiming point when aligning your chrono with your rifle’s bore. If you use a 2″ bright orange dot, you should be able to see that through the bore at 100 yards. Using a single 2″ target reduces the chance of a screen hit as you shift points of aim. If you shoot at multiple target dots, place them in a vertical line, and bore sight on the lowest dot. Always set your chron height to set safe clearance for the LOWEST target dot, and then work upwards only.
Other Chronograph Tips from Forum Members:
When using a chronograph, I put a strip of masking tape across the far end of the skyscreens about two-thirds of the way up. This gives me a good aiming or bore-sighting reference that’s well away from the pricey bits. I learned that one the hard way. — German Salazar
A very easy and simple tool to help you set up the chronograph is a simple piece of string! Set your gun (unloaded of course) on the rest and sight your target. Tie one end of the string to the rear scope ring or mount, then pull the string along the barrel to simulate the bullet path. With the string showing the bullet’s path, you can then easily set the chronograph’s placement left/right, and up/down. This will also let you set the chrono’s tilt angle and orientation so the sensors are correctly aligned with the bullet path. — Wayne Shaw
If shooting over a chrono from the prone position off a bipod or similar, beware of the muzzle sinking as recoil causes the front of the rifle to drop. I “killed” my first chronograph shooting off a gravel covered firing point where I’d not given enough clearance to start with and an inch or two drop in the muzzle caused a bullet to clip the housing. — Laurie Holland
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This an older video from the YouTube archives but we expect many readers have still not seen it yet. It definitely teaches an important lesson — never underestimate the destructive power of rifle-launched projectiles. What appears a “safe distance” from steel may actually be well within the danger zone.
In this video a rather ignorant (yet lucky) fellow demonstrates what NOT to do with a large-caliber rifle (a 50 BMG apparently). He shoots at a steel target about 70 yards away and a bullet fragment comes back directly at him. He was lucky enough that the ricochet just smacked his left ear muff. Another inch to the right and he could have lost his eye… or worse.
If you have ever done much action pistol shooting at close range on steel targets, you’ll know about the hazards of ricochets and bullet splashback. That’s why you should only shoot low-velocity rounds with soft lead or frangible bullets when shooting at relatively close range.
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Have you ever seen bullet trace? Do you know how to read trace? Well watch this NSSF video to learn how to recognize trace, and use trace to help adjust your aim on the target. Watch the video from 1:50 to 2:20 to see trace in slow motion. Watch carefully starting and you can see the trace in the milli-seconds before the bullet hits the target.
Rod Ryan of Storm Mountain Training Center explains how to read bullet trace: “If you’re looking through your spotting scope, and you focus on your target, and then back off about a quarter-turn counter-clockwise (in most cases) you’ll be able to focus a little closer to you and you’ll actually see this movement of air — it’s called the trace — going down range.”
Watch the Slow-Mo Trace Starting at 1:50. From 2:10 to 2:20 you can actually see the bullet hanging in the air just before it hits the target.
Trace is easier to see when there’s some moisture in the air. By following the bullet trace you can see if you shot is running high or low, left or right, even if you can’t see a shot imparct on the target. This is important, particularly when you’re attempting an steep-angled shot and it’s hard to see bullet impact on the ground near the target. Rod Ryan explains: “A lot of times we have an angular hill-top and you’re shooting directly into a [steep] drop [so] you can’t see any splash at all or any dirt flow after the miss happens. In this case the last thing you see is that trace.”
What you’re seeing is akin to the wake that forms behind a motorboat, but it is a trail of disturbed air rather than disturbed water. Ryan says: “It’s just like you’re looking down from space at a motorboat in the water, you can see that wake. Very close to the target, you can actually see it roll in… if you’re taking a shot at say… four, five, six hundred yards, it’s very prevalent, you can see it very well.”
Video find by EdLongrange. We welcome reader submissions.
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Here’s a valuable web resource our readers should bookmark for easy access in the future. ShootForum.com offers a vast Bullet Database, which includes roughly 3900 bullet designs in all. We counted nearly 200 different 6mm bullets! The bullet info comes from the makers of QuickLOAD Software. Access to the online database is FREE. Most database entries include Caliber, Manufacturer, Stated Bullet Weight, True Bullet Weight, Length, Sectional Density (SD), and Ballistic Coefficient.* In many cases multiple BCs are provided for different velocity ranges.
The database is great if you’re looking for an unusual caliber, or you want a non-standard bullet diameter to fit a barrel that is tighter or looser than spec. You’ll find the popular jacketed bullets from major makers, plus solids, plated bullets, and even cast bullets. For those who don’t already own QuickLOAD software, this is a great resource, providing access to a wealth of bullet information.
Values for Changed Bullet Designs
Some of our readers have noted some variances with BCs and OALs with recently changed bullet designs. In general the database is very useful and accurate. However, as with any data resource this extensive, there will be a few items that need to be updated. Manufacturers can and do modify bullet shapes. Kevin Adams, one of the creators of the database, explains: “Thanks for mentioning this database. It took us a long time to collate this information and have agreement to publish it. Please keep in mind that individual batches of bullets will differ from the manufacturers’ stated standards. This is more a reflection on the manufacturers’ tolerances than the database ‘accuracy’. We will continue to add to the database as more manufacturers’ figures come available.”
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In 2016, Hornady will introduce new hunting and match bullets with high-tech, heat resistant tips. Hornady developed the new “Heat Shield” bullet tips after Doppler Radar testing showed that the Ballistic Coefficients (BCs) of old-style tipped bullets were degrading in flight in an unexplained manner. Hornady’s engineers theorized that the old-style plastic bullet tips were deforming in flight due to heat and pressure. Hornady claims this problem occurred with high-BC (0.5+ G1) tipped bullets from a variety of manufacturers. Hornady’s testers believed that, after 150 yards or so, the tips on high-BC bullets were actually melting at the front. That enlarged the meplat, resulting in increased drag.*
Consequently, Hornady developed a new type of bullet tip made from a heat-resistant polymer. Further long-range Doppler Radar testing seemingly confirmed that bullets equipped with the new tips did not suffer from the BC loss previously found. This allowed the bullets to maintain a higher, more consistent BC during the entire trajectory. The end result is a bullet with reduced vertical dispersion at long range (or so Hornady claims).
New Hornady ELD-X Hunting Bullets
For 2016, Hornady will bring out two lines of projectiles using the new tips. The first line of bullets, designed for hunting, will be called ELD-X, standing for “Extreme Low Drag eXpanding”. These feature dark red, translucent, heat-resistant tips. With interlock-style internal construction, these hunting projectiles are designed to yield deep penetration and excellent weight retention. Hornady will offer seven different ELD-X bullet types, ranging in weight from 143 grains (6.5mm) to 220 grains (.30 Cal):
NOTE: We don’t know if the stated BC values are based on drag models or actual range testing. These new ELD-X hunting bullets will be loaded into a new line of Precision Hunter Ammo for a variety of popular hunting cartridges.
New Hornady ELD Match Bullets
Along with its new hunting bullets, Hornady is coming out with a line of ELD Match bullets as well. Hornady’s engineers say the new molded “Heat Shield Tip” should be a boon to competitive shooters: “You can’t point up that copper [tip] as consistently as you can mold a plastic tip. With the ELD Match line, and the Heat Shield Tip technology… we now have a perfected meplat. These bullets allow you to shoot groups with less vertical deviation, or less vertical stringing, because the bullets are exact in their drag [factor].” There are currently four bullets in the ELD Match line:
Hornady will offer factory ammunition loaded with ELD Match bullets, starting with 6.5 Creedmoor ammo loaded with the 140gr ELD, and .338 Lapua Magnum ammo loaded with the 285gr ELD.
Better Tips Make a Difference — But other Factors Are Important
Hornady claims that its new Heat Shield Tips are more uniform than the meplats on conventional jacketed, hollow-point bullets. This, Hornady says, should provide greater bullet-to-bullet BC consistency than is possible with conventional, non-tipped bullets.
We have heard such claims before. Plastic tips are good, so long as they are inserted perfectly in the bullet. But sometimes they are crooked (off-axis) — we’ve seen that with various brands of tipped projectiles. Other factors will affect bullet performance as well, such as bullet weight, bullet diameter, and bullet bearing surface length. Even with perfectly uniform bullet tips, if bullet weights or diameters are inconsistent across a sample, you can still have accuracy issues (and pressure-related velocity variances). Likewise, if the bearing surface lengths vary considerably from one bullet to the next, this can increase velocity spread and otherwise have a deleterious effect on accuracy.
So, overall, we think Hornady has probably engineered a better bullet tip, which is a good thing. On the other hand there are many other factors (beyond tip uniformity) involved in long-range bullet performance. It will be interesting to test the new ELD Match bullets to see how they compare with the best hollow point jacketed bullets from other manufacturers.
MORE TECHNICAL DETAILS
* Hornady’s Chief Ballistician Dave Emary authored a technical report based on the Doppler Radar testing of a variety of tipped Bullets. CLICK HERE for Emary Report. Here are some of the report’s key observations and conclusions:
After early testing of prototype bullets it was observed that all currently manufactured tipped projectiles’ drag curves were convex, not concave and that abnormally low ballistic coefficients were being observed over long ranges. The drag was rapidly increasing at high velocities.
At this point extensive testing was done with all types of commercially-available tipped projectiles. They all exhibited this behavior to a greater or lesser extent depending on their ballistic coefficient and launch velocity. Most projectiles exhibited BCs relatively close to published values for 150 to 200 yards of flight. Beyond these distances they all showed BCs substantially below published values.
It was obvious that something was changing in the tipped projectiles to cause a rapid increase in drag at higher velocities. The drag increases were most noticeable from 100 to about 500 yards. Drag increases stopped at velocities below approximately 2,100 fps. This behavior was not observed with hollow point or exposed lead (spitzer) style designs. The problem magnified as the velocity was increased. The problem was worse for heavier, higher-BC projectiles that maintained higher velocities longer. After some consideration the answer was obvious and one that several people had wondered about for some time but had no way to prove their thoughts.
The tip of a bullet at 3,000 fps will see temperatures as high as 850 degrees F and decreasing as
the bullet slows down. These temperatures on the tip were a known fact. What wasn’t known was how long it would take at these peak and decreasing temperatures for the polymer tips to begin showing effects, if at all. As it turns out it is within the first 100 yards of flight. Currently-used polymers in projectile tips begin to have properties like rubber at approximately -65 to 50 degrees F and will melt at 300 to 350 degrees F, depending on the exact polymer.
All current polymer-tipped projectiles have tips that are at best softening and deforming in flight and under many circumstances melting and badly deforming. To cut through a lot of technical discussion the problem becomes worse at higher ambient air temperatures (summer) and higher launch velocities. Projectiles that have a high BC and retain velocity well see higher stagnation temperatures for longer lengths of time and have greater degradation of the tip. Simply put it is a heat capacity problem –temperature times time. This makes BCs for current tipped projectiles a rough average over some distance, dependent on atmospheric conditions and muzzle velocity, and does not allow the accurate prediction of downrange ballistics much beyond 400 yards.
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Tech Tip by Doc Beech, Applied Ballistics Support Team
I am going to hit on some key points when it comes to bullet pointing. How much pointing and trimming needed is going to depend on the bullet itself. Specifically how bad the bullets are to begin with. Starting out with better-quality projectiles such as Bergers is going to mean two things. First that you don’t need to do as much correction to the meplat, but also that the improvement is going to be less. NOTE: We recommend you DO NOT POINT hunting bullets. Pointing can affect terminal performance in a bad way.
NOTE the change in the bullet tip shape and hollowpoint size after pointing:
Don’t Over-Point Your Bullets
What is important here is that you never want to over-point. It is far better to be safe, and under-point, rather than over-point and crush the tips even the slightest bit. To quote Bryan Litz exactly: “Best practice is to leave a tiny air gap in the tip so you’re sure not to compress the metal together which will result in crushing. Most of the gain in pointing is taking the bullet tip down to this point. Going a little further doesn’t show on target”. So in essence you are only bringing the tip down a small amount… and you want to make sure you leave an air gap at the tip.
Also keep in mind, bullet pointing is one of those procedures with variable returns. If you only shoot at 100-200 yards, bullet pointing will likely not benefit you. To see the benefits, which can run from 2 to 10% (possibly more with poorly designed bullets), you need be shooting at long range. Bryan says: “Typically, with pointing, you’ll see 3-4% increase in BC on average. If the nose is long and pointy (VLD shape) with a large meplat, that’s where pointing has the biggest effect; up to 8% or 10%. If the meplat is tight on a short tangent nose, the increase can be as small as 1 or 2%.” For example, If you point a Berger .308-caliber 185gr Juggernaut expect to only get a 2% increase in BC.
Should You Trim after Pointing?
Sometimes you can see tiny imperfections after pointing, but to say you “need” to trim after pointing is to say that the small imperfections make a difference. Bryan Litz advises: “If your goal is to make bullets that fly uniformly at the highest levels, it may not be necessary to trim them.” In fact Bryan states: “I’ve never trimmed a bullet tip, before or after pointing”. So in the end it is up to you to decide.
Pointing is Easy with the Right Tools
The process of pointing in itself is very simple. It takes about as much effort to point bullets as it does to seat bullets. We are simply making the air gap on the tip of the bullet ever-so smaller. Don’t rush the job — go slow. Use smooth and steady pressure on the press when pointing bullets. You don’t want to trap air in the die and damage the bullet tip. You can use most any press, with a caliber-specific sleeve and correct die insert. The Whidden pointing die has a micrometer top so making adjustments is very easy.
Bryan Litz actually helped design the Whidden Bullet Pointing Die System, so you can order the Pointing Die and Inserts directly from Applied Ballistics. Just make sure that you pick up the correct caliber sleeve(s) and appropriate insert(s). As sold by Applied Ballistics, the Whidden Bullet Pointing Die System comes with the die, one tipping insert, and one caliber-specific sleeve. To see which insert(s) you need for your bullet type(s), click this link:
Need a boatload of bullets for varmint safaris, or high-volume AR-platform training sessions? Then check out this deal from Midsouth Shooters Supply. Right now you can get six THOUSAND .22-Cal 55gr softpoint bullets for $463.66 delivered. That works out to just $7.73 per 100 bullets. And yes, for a limited time, that price includes FREE Shipping (through August 28, 2015). If you have high-volume applications for .224-diameter projectiles, this deal is hard to beat. You could easily pay two to three tiems as much (per hundred) for similar bullets elsewhere. Buying in bulk saves big bucks.
These 55g Soft Point bullets are made by Hornady. The G1 Ballistic Coefficient (BC) is 0.243. Hornady says these bullets have a “match-grade jacket design” and offer “explosive expansion, even at low velocities”. NOTE: Midsouth also offers Hornady FMJ 55gr 22-cal bullets at low bulk prices.
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Georgia-based PolyCase Ammunition has developed innovative polymer-based composite cartridge cases and injection-molded bullets. With a patent-pending design, the polymer cartridge cases are lighter than brass or steel cases, yet are heat-tolerant, and relatively easy to manufacture. These cases will be initially produced for .223 Remington, plus a variety of pistol cartridge types (.380 ACP, .38 SPL, 9mm Luger). PolyCase cartridge cases blend patented heat-resistent polymers with metal elements in the case base. According to the manufacturer, “the net effects are greatly reduced weight (compared to comparable loaded ammunition), durability… and competitive pricing.” Other companies have experimented with polymer cartridge cases in the past — none have successfully perfected the technology in a commercially successful product. Could PolyCase be the first?
PolyCase Ammunition — Material Characteristics
– PolyCase Pistol Cartridge Cases are 11.5 to 20% lighter than brass-cased ammunition.
– PolyCase Rifle Cartridge Cases are 23 to 60% lighter than brass-cased ammunition.
– PolyCase Cartridge Cases are self-lubricating — a positive factor compared to brass or steel cases.
PolyCase Bullets — Injection-Molded Blend of Copper and Plastic
PolyCase has developed its own unique bullets for use in pistol ammunition. PolyCase Cu/P™ bullets are precision injection-molded from a cutting-edge copper-polymer compound. These molded bullets will be offered in both polymer cases and conventional brass cases. (Early in the design process, PolyCase determined that molded bullets work well in both brass and plastic cases). PolyCase co-owner Paul Lemke (Lt. Col. U.S. Army, Ret.) says: “We are able to use essentially the same molds to produce bullets for brass casings and bullets for our polymer casings”.
PolyCase Pioneers Injection-Molded Bullet Technology
Powdered metal has been around for decades, but blending powdered metal with polymers and injection molding precise parts is a fairly modern process. While processes like sintered metal bullets and pressure-formed shotgun pellets have become commonplace, PolyCase is the first American company to produce and sell a completely injection-molded bullet.
For over a century most bullets have been mass-produced with a process called cold-forming. Lead and copper were shaped with brute force in punches and dies to create projectiles. While this is still a viable and effective way to produce bullets, other manufacturing methods are now available. By applying injection-molding technology, Polycase has developed a new type of bullet that has many advantages, as least for handgun applications. Bullets weigh approximately 70% as much as lead bullets with similar profiles. Lighter weight means higher velocities and less recoil. In addition, PolyCase bullets are lead-free, and low ricochet — two qualities important for indoor and close-range training. The injection-molding process also reduces weight variations (compared to cast lead bullets), and ensures excellent concentricity. Molding also allows unique shapes that are impossible to produce with conventional bullet-making methods (see photo).
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Here is a simple technique that can potentially help you load straighter ammo, with less run-out. It costs nothing and adds only a few seconds to the time needed to load a cartridge. Next time you’re loading ammo with a threaded (screw-in) seating die, try seating the bullet in two stages. Run the cartridge up in the seating die just enough to seat the bullet half way. Then lower the cartridge and rotate it 180° in the shell-holder. Now raise the cartridge up into the die again and finish seating the bullet.
Steve, aka “Short Range”, one of our Forum members, recently inquired about run-out apparently caused by his bullet-seating process. Steve’s 30BR cases were coming out of his neck-sizer with good concentricity, but the run-out nearly doubled after he seated the bullets. At the suggestion of other Forum members, Steve tried the process of rotating his cartridge while seating his bullet. Steve then measured run-out on his loaded rounds. To his surprise there was a noticeable reduction in run-out on the cases which had been rotated during seating. Steve explains: “For the rounds that I loaded yesterday, I seated the bullet half-way, and turned the round 180 degrees, and finished seating the bullet. That reduced the bullet runout by almost half on most rounds compared to the measurements from the first test.”
Steve recorded run-out measurements on his 30BR brass using both the conventional (one-pass) seating procedure, as well as the two-stage (with 180° rotation) method. Steve’s measurements are collected in the two charts above. As you can see, the run-out was less for the rounds which were rotated during seating. Note, the change is pretty small (less than .001″ on average), but every little bit helps in the accuracy game. If you use a threaded (screw-in) seating die, you might try this two-stage bullet-seating method. Rotating your case in the middle of the seating process won’t cost you a penny, and it just might produce straighter ammo (nothing is guaranteed). If you do NOT see any improvement on the target, you can always go back to seating your bullets in one pass. READ Forum Thread….
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Berger Bullets has improved its online stability calculator. Tests have shown that bullets can suffer from reduced BC if the bullet rpm (spin rate) is less than optimal, even if barrel twist rate is otherwise fast enough to stabilize bullets in flight. Now, the improved, free Stability Calculator can determine if you need a faster-twist barrel to enjoy the best BC from your bullets.
By Bryan Litz, Chief Ballistician forBerger Bullets
We’re happy to announce a major upgrade to our Twist Rate Stability Calculator which is free to use on the Berger Bullets webpage. The old stability calculator was pretty basic, and would simply return a gyroscopic stability number based on your bullet, twist rate, and atmospheric conditions. This was used to determine if your barrels twist rate was fast enough to stabilize a particular bullet or not, based on the Gyroscopic Stability Factor (SG) being greater than 1.4.
Stability and BC — How Bullet RPM Affects Ballistic Coefficients
The new calculator still calculates SG, but also goes much further. In addition to calculating stability, the upgraded calculator can also tell you if your stability level is harming the effective BC of your bullets or not. Extensive testing has proven that bullets fired with stability levels between 1.2 and 1.5 can fly with excellent precision (good groups), but suffer from a depressed BC, sometimes as much as 10%. Shooting the bullets from faster twist rate barrels allows for the bullets to fly better and realize their full BC potential.
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Need something for the walls of your “man cave” or reloading room? Check out these jumbo-size cartridge posters. The creators of the Cartridge Comparison Guide now offer three very large full-color printed posters. These can be tacked to a wall or matted/framed to hang like paintings. Three different posters are available.
Rifleman’s Classic Poster (38″ x 27″)
The Rifleman’s Classic Poster, a full 38 inches wide and 27 inches tall, is the most comprehensive. This $19.95 poster displays 272 rifle cartridge types at true size (within 4/1000 of an inch). Cartridges shown range from .17 caliber all the way up to the big boomers (including some cannon shells). The Rifleman’s Classic poster includes all American Standardized Rifle Cartridges (as of 2013) and many European rifle cartridges. The poster is a good representation of military cartridges dating back to WWI and includes cartridges such as the 13X92mm MSR and the .55 Boys.
CLICK Image to Enlarge:
American Standard Cartridge Poster (Rifle, Handgun, Shotgun) — $15.95
The 36″ x 24″ American Standard Poster displays 165 rifle cartridges, 55 handgun cartridges, and 9 different shotgun gauges. This includes all American Standardized Cartridges (rifle, handgun, and shotgun) available as of January 2012. All cartridge types are displayed in full color, actual size. The rifle selection includes all standard hunting cartridges from the 17 Mach 2 through the .505 Gibbs and .577 Nitro. Bonus cartridges include the .375 and .408 Chey-Tac, .416 Barrett, .50 BMG, 50-20 and 20mm. The Handgun section covers cartridges from the 17 HMR to the 500 S&W. Shotgun cartridges include the .410 and 32 gauge up to the 8 gauge. NOTE: Wildcat, proprietary, and obsolete-historic cartridges are NOT included in this poster.
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BIG BORE Cartridge Poster (215 Cartridges) — $15.95
The 36″ x 24″ Big Bore Poster illustrates over 215 large=caliber rifle cartridges, all shown actual size in full color. These include Standard, Historic, Military, Proprietary and Wildcat rifle cartridges side by side. Cartridges illustrated range from the subsonic .338 Spectre up to the monstrous .729 Jongmans. The poster also includes historically significant cartridges such as the 12 Gauge Paradox, 4 Bore, 1″ Nordfelt, 50 BAT Spotter, .50 BMG, .5 Vickers, 12.7×108 Russian, 20mm, 25mm, 30mm and more.
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Waterloo Labs is a group of engineers from National Instruments and other self-declared “nerds” from Austin, Texas. These folks conducted an interesting demonstration using electronic accelerometers to plot bullet impacts from a suppressed Ruger MKIII .22LR pistol. The accelerometers respond to vibrations caused when the bullets hit a drywall target backer. By triangulating data from multiple accelerometers, each shot’s exact point of impact can be plotted with great precision. These point-of-impact coordinates are then fed into a computer and super-imposed into a Flash version of the Half-Life video game (which is projected on the drywall board). The end result is being able to “play” a video game with a real firearm.
Do-It-Yourself Electronic Target System?
Now, we are NOT particularly interested in shooting Zombies in a video game. However, the technology has interesting potential applications for real shooters. Waterloo Labs has published the computer code, used to triangulate bullet impacts from multiple accelerometers. Potentially, a system like this could be built to provide display and scoring of long-range targets. Sophisticated electronic target systems already exist, but they use proprietary hardware and software, and they are very expensive. The Waterloo Labs experiment shows that shooters with some computer and electronic skills could build their own electronic scoring system, one that can be adapted to a variety of target sizes and materials.
In addition, we imagine this system could be utilized for military and law enforcement training. The walls of structures used for “live-fire” room-clearing exercises could be fitted with accelerometers so the bullet impacts could be plotted and studied. Then, later, the impact plots could be combined with a computer simulation so that trainees could “replay” their live-fire sessions, viewing the actual location of their hits (and misses).
Lapua just dropped a bombshell — multiple bombshells, in fact. Lapua just announced that it will be producing .221 Fireball brass and .50 BMG brass starting early 2014. This will be the first truly match-grade brass ever offered for the .221 Fireball. That’s great news for varminters, who can use Lapua’s new .221 Fireball brass “as is” or neck it down to .20 Vartarg or 17 Fireball. Tactical shooters can also use the .221 Fireball brass to make the .300 Whisper and 300 Blackout sub-sonic cartridges. At the other end of the spectrum, ultra-long-range shooters now have a new ultra-premium brass source for the mighty .50 BMG. This is potentially a “game-changer” for fifty-cal shooters who have had to “make do” with military surplus brass for the most part. Lapua says the new brass, both .50 BMG and .221 Fireball, should be in the USA by early April, 2014. Sorry, no pricing info is yet available.
Here is the Lapua Product Announcement for .221 Fireball and .50 BMG Brass:
New 180-Grain and 150-Grain 7mm Scenar-L Bullets
The other big news from Lapua is the release of two new 7mm (.284 caliber) Scenar-L target bullets. Recognizing the popularity of 7mm cartridges among F-Class Open Division shooters, Lapua will offer a high-BC, 180-grain bullet. As part of the “L” series, this new 180-grainer bullet should exhibit extreme consistency in base-to-ogive measurements and bullet weight. We expect this new 180gr projectile to be extremely accurate in the .284 Winchester, .284 Shehane, 7mm WSM, and 7mm RSAUM — popular chamberings for F-Class and long-range benchrest shooters. No BC information has been released yet, but we expect the BC number to be quite high, giving this bullet great wind-bucking capability. In addition to the new 180gr 7mm Scenar-L, Lapua will offer a new 150gr 7mm bullet. This is optimized for medium range competition in Silhouette and Across-the-Course competition. It should offer great accuracy, but with less felt recoil than its 180-grain bigger brother.
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The last primary lead smelter facility in the United States will be closing soon. The Doe Run Company smelter in Herculaneum, Missouri has been operating since 1892. The facility will be closed permanently under pressure from the EPA. According to MSNBC.com: “Doe Run Co. was ordered by the EPA to install new pollution control technologies needed to reduce sulfur dioxide and lead emissions as required by the Clean Air Act. The company will instead close its lead smelter.”
Doe Run started life in 1864 as the St. Joseph Lead Company, better known as St. Joe, which started lead mining on a small scale in southeastern Missouri. In 1892 it started up its smelter in Herculaneum, where all smelting was consolidated in 1920.
Cause for Concern? Our readers have been concerned that the closure of the Doe Run smelter will lead to serious shortages in raw materials for bullet-making. Readers fear that bullet-makers won’t be able to source lead, and so the output of bullets and ammo would be reduced. Curtailed bullet production would lead to higher prices, it is feared.
As it turns out, the situation is not as dire as it seems. At least one bullet-maker says the Doe Run smelter closure will have no immediate effect on its raw material supply chain.
Sierra Bullets Responds: Lead Smelter Closure Should Not Cause Supply Shortage
Addressing the issue of supply shortages, Sierra Bullets posted a notice in the Sierra Blog on November 1, 2013. Sierra Bullets Plant Engineer Darren Leskiw stated that the Doe Run smelter closure should create no problems for his company because it uses only recycled lead:
We have had many customers contact us about the closing of the last primary lead smelting facility in the USA. This facility is operated by Doe Run and is located in Herculaneum, Missouri and is just about a 3-hour drive from our facility in Sedalia, Missouri.
The main question asked is “Will this shut down your supply of lead?” The answer to that is no. First, Sierra buys lead from several different vendors to maintain constant supply. Second, this facility only smelts primary lead or lead ore. This is lead ore that has just been brought out of the earth. Sierra uses no primary lead at all and never has, so we use nothing directly from this facility. The lead we buy from Doe Run comes from their recycling facility in Boss, MO that is about 90 miles away from the smelter that is closing.
The facility we buy from is still going strong and delivering to us as scheduled. The lead from this facility is from recycled lead, mostly coming from car batteries. This is a continuing “in and out” cycle for them and the smelter closing will not affect this facility.
Our supply should not be in jeopardy and we do not anticipate any changes in our supply chain at this time. Could the lack of primary lead create a little more demand for recycled lead? Sure, but how much is unknown. Could this increase in demand also create an increase in price? Sure, but again, by how much is unknown at this time.
There are many other primary lead smelters in the world and so the flow of primary lead will not be shut off. Where there is a need for primary lead, I am sure there will be a salesman more than happy to pick up the business. In short, we do not see any reason for alarm. We expect our supply to continue and keep feeding our production lines which are still running 24 hours per day to return our inventory levels to where they should be.
Lead Smelting Operations Have Moved to Mexico
Posting on SnipersHide.com, one industry insider says shooters should not be overly concerned about the Doe Run shut-down, because smelting is still being done in nearby Mexico:
“The lead industry has been transitioning out of the United States for over a decade now. 85% of the lead smelting industry capacity migrated over the Mexican border where there are [fewer environmental regulations]. The remainder of production capacity will be online and running by the third quarter of 2014. There has been no production disruption to speak of in obtaining lead or lead products. The auto battery industry among others has prepared for this eventuality for some time….
The last lead smelter closing in December did not have enough capacity to supply even 10% of the battery industry much less the ammunition industry. The lead being used in ammunition today hasn’t been coming from the United States for years already. The closing of that plant will not have any appreciable effect on lead availability at all. There is a great deal of lead processed here being extruded, made into shot, converted to wire, etc., but the smelting operation is only one part of the production process.”
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On the Applied Ballistics Facebook page, Ballistician Bryan Litz regularly offers a “Tuesday Trivia” question about ballistics. Today’s brain-teaser is a true/false question about bullet stabilization. On shooting forums you often find heated arguments about “over-stabilization”. Bryan wants readers to consider the issue of over-stabilization and answer a challenge question…
Is This Statement TRUE or FALSE?
“The problem with ‘over-stabilizing’ a bullet (by shooting it from an excessively fast twist rate) is that the bullet will fly ‘nose high’ on a long range shot. The nose-high orientation induces extra drag and reduces the effective BC of the bullet.”
True or False, and WHY?
Click the “Post Comment” link below to post your reply (and explain your reasoning).
Bullet Movement in Flight — More Complicated Than You May Think
Bullets do not follow a laser beam-like, perfectly straight line to the target, nor does the nose of the bullet always point exactly at the point of aim. Multiple forces are in effect that may cause the bullet to yaw (rotate side to side around its axis), tilt nose-up (pitch), or precess (like a spinning top) in flight. These effects (in exaggerated form) are shown below:
Yaw refers to movement of the nose of the bullet away from the line of flight. Precession is a change in the orientation of the rotational axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second Euler angle (nutation) is constant. In physics, there are two types of precession: torque-free and torque-induced. Nutation refers to small circular movement at the bullet tip.
In order to increase deliveries of its most popular types of ammunition and bullets, Hornady announced that it will temporarily suspend production of 150 bullet types and 150 ammo types. IMPORTANT: These bullet and ammo products are NOT being discontinued. Rather, these less-popular, suspended items will simply not be produced for the remainder of 2013. By doing this, Hornady can reduce tool/machinery changes and thereby increase production of products in highest demand. On July 2nd, Hornady issued this statement:
Dear Hornady Customer:
As you are aware, 2013 has been one of the most challenging years ever in the sporting arms industry. We are proud of the increases in production we have achieved this year, but we are still faced witha demand that exceeds our ability to produce.
In efforts to increase production, we have reviewed everything, refining procedures, adding people, and equipment when possible. One area that will help us produce more: cutting the number of changeovers in our production machinery.
In order to reduce changeovers, we are announceing the temporary suspension of over 150 ammunition items and 150 bullet items, for the balance of 2013.
Attached you will find the list of items that will be suspended. Our plan is to remove the orders for these items from our system, beginning July 10th, and notify you of the cancellations. We will continue to monitor and update this list as the market conditions change.
Our goal is to try to deliver more to every customer, and while this may impact certain categories, our overall delivery should improve.
Hornady has listed the suspended bullet/ammo items in ten pages of attachments sent out to Hornady wholesalers and retailers. One representative page (covering 6mm, 6.5mm, and 7mm bullets) is shown below. This is NOT the complete list — there are TEN (10) pages! Click on each link below to see suspended items listed by caliber, small to large.
Notable Bullets on the Suspended List:
22832 – 22 Cal .224 80gr A-Max
22420 – 6mm .243 75gr V-Max
24562 – 6mm .243 105gr A-Max
26101 – 6.5mm .243 100gr A-Max
29402 – 7mm .284 162gr A-Max
29405 – 7mm .285 162gr BTHP Match
30314 – 30 Cal .308 155gr A-Max Moly
30715 – 30 Cal .308 178gr BTHP Match
30733 – 30 Cal .308 208gr BTHP Match
33102 – 338 Cal .338 200gr SST
Note, the above selection of “notable bullets” is just a “short list” of items that caught our attention. Remember 150 bullet types are being suspended for the balance of the year. With some items on the list, partial orders will be filled, or current orders will be filled, but no new orders taken.
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