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February 28th, 2009
 The Ballistic Coefficient (BC) of a bullet is an index number used to describe the bullet’s aerodynamic drag relative to a reference standard. While bullet manufacturers commonly include BCs in their product descriptions, often times those numbers are merely a mathematical calculation, rather than the result of actual testing. Also, since the true drag of a bullet changes over the course of its trajectory, using a single BC is a fairly primitive way to predict how that bullet will actually perform over a long distance.
Lapua is now using Doppler radar to provide a more sophisticated model of bullet flight. Lapua has issued drag coefficients for its bullets based on radar testing. Importantly, Lapua didn’t just calculate drag coefficients off bullet blueprints. Instead, Lapua used radar to measure bullet velocities at various points along the bullet flight path (trajectory). This provides Cd (Coefficient of Drag) values that can be used with advanced ballistic software such as QuickTARGET to calculate trajectories with great reliability and precision.
Lapua’s engineers explain: “With our Cd-data measured by continuous Doppler radar measurements you can calculate the trajectory of your bullet much more accurately than using the simplified one-number BC. Typically-used simple ballistic coefficient (BC) describes only ballistic performance of the bullet compared to old standard ‘G1′ bullet. Ballistic Coefficient is essentially a measure of drag force compared to G1 projectile. The higher the BC value, the less drag and better ballistic performance.
The BC changes during a projectile‘s flight and stated BCs are always averages for particular velocity ranges. Knowing how a BC was established is almost as important as knowing the stated BC value itself. For the precise establishment of bullet trajectory, Doppler radar-measurements are required. The normal shooter however, has no access to such expensive professional measurement devices.
The radar-measured Cd factor describes the aerodynamic drag at particular points of trajectory. A Cd table (see above) shows this factor as a function of velocity (Mach number). Special software is required (e.g. Quick Target Unlimited) to utilize this data to [generate a] ballistic table. During the Doppler radar measurements the complete location information versus time is recorded.”
Long-Range Tests Show Lapua’s Bullet Drag Models Work Well
One of our sources has been working with Lapua’s radar-derived ballistic data for over a year. His task was to see how calculated trajectories using Lapua’s stated Cd values for particular bullets compared to observed bullet flights at long range. Using the data for the Lapua 250gr Scenar, this tester found the predicted trajectory “dead on to 1600 meters (about a mile) and only a few click off [at] 2000 meter (1.25 mile) distances”.
Bullet Ballistic Info for Download
CLICK HERE for explanation of Doppler-derived Cd with sample charts.
CLICK HERE for Cd-data for Lapua bullets.
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January 22nd, 2009
Now through the end of January, MidwayUSA is offering “blemished bullets” from major manufacturers at deep discounts — up to 40% off. These blemished bullets are bulk-packed factory seconds from major manufacturers. For most bullets, the blemish consists of slight discolorations in the jacket. Click the links below for specific calibers:
20 Cal Blems | 22 Cal Blems | 6mm Blems | 7mm Blems
Among the better blemished bullet offerings are:
 20 Caliber (.204 Diameter) 45gr Soft Point Box of 100
Product #786503
Price: $13.49 marked down from $22.49.
22 Caliber (.224 Diameter) 55gr Soft Point Box of 100
Product #324450
Price: $8.89 marked down from $14.79.
270 Caliber (.277 Diameter) 140gr Spitzer BT Box of 100
Product #491606
Price: $13.49 marked down from $22.49.
7mm (.284 Diam.) 154gr Bonded Spitzer BT (Plastic Tip) Box of 100
Product #377637
Price: $26.99 marked down from $44.99.
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January 19th, 2009
RCBS makes a fine progressive press, the RCBS Pro 2000. This Editor owns one. I can tell you it is very solid, and the strip primer-feeding system has proven virtually fool-proof, something that can’t be said about some competitive progressive presses. I also believe the micrometer-equipped powder measure is superior to the Dillon alternative. Nonetheless, Dillon still dominates the progressive press market. One reason is that Dillon has long offered a reliable case-feeding system, and GSI International and Gaspari USA offer after-market bullet feeders for the Dillon 650 and 1050. Until now, with an RCBS Progressive, you needed to manually insert a bullet into each case. Well, at SHOT 2009, RCBS unveiled a new bullet-feeding system.
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RCBS says its new automatic bullet-feeder will work with Dillon (blue) and Hornady (red) progressives as well as the RCBS 2000. The unit mounts to a sturdy vertical support, with a flexible tube that connects to the bullet-seating station. It looks well-designed, and during a demo by RCBS manager Kent Sakamoto, the bullet-feeding system worked flawlessly. Kent showed us the pistol-bullet feeder, but a second version for rifle bullets will be offered by mid-2009. The rifle-bullet feeder should be just the ticket for varminters who need to load large quantities of .223 Rem, 22-250, or .204 Ruger rounds. Sakamoto explained that the automatic bullet feeder can significantly boost your reloading output whether you have a blue, red, or green progressive press.
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January 16th, 2009
Jason’s first stop on his 2009 SHOT Show tour was at the Berger Bullets booth. Our readers know that Berger manufactures some of the best varmint and match bullets in the world. Eric Stecker, Berger’s master bulletsmith, announced that Berger is organizing its production into three main lines: Varmint bullets (flat-base and standard boat-tails), Target bullets (both Tangent Ogive and VLD designs) with thicker jackets, and Hunting bullets (low-drag VLD with standard J4 jackets).
A design effort is underway to optimize the “long range” bullet shapes, centering around a tangent ogive BT design with shorter than normal bearing surface. This allows a longer nose shape with a better BC. It should also be easier to tune, given the tangent ogive design. Berger’s designers are also working with a double ogive shape for big bore bullets. This will feature a tangent ogive immediately above the bearing surface to allow a smoother transition into the lands. Then the shape transitions to a secant ogive for better BC and a smaller meplat.
New 20 Caliber Bullet is Ready and Two .338 Projectiles in the Works
Berger announced a new 55gr, 20-caliber “Long Range” BT bullet. Prototypes have been tested successfully in 8-twist barrels. With sufficient velocities a 1:9″ twist might work also, but Berger wants more field testing–by shooters like you. NOTE: Berger is currently looking for “volunteers” to test this new 20-cal 55-grainer in 8-Twist and 9-Twist barrels. Contact Michelle Gallagher at Berger for more details.
Big-bore shooters will be pleased to learn Berger hopes to release both 250gr and 300gr .338-caliber bullets by the end of 2009. While design work is on-going, Berger expects to offer tangent ogive, secant ogive, and double-radius .338 projectiles in both 250gr and 300gr weights. So you’ll have a choice of three different bullet shapes, each in two weights. That’s good news for hunters and ultra-long-range shooters.
Bullet Ballistic Coefficients (BCs) to Be Analyzed and Updated
Berger recently hired Bryan Litz as an in-house ballistics experts. Bryan, a top-level High Power and long-range shooter, formerly worked with the Air Force as a rocket ballistics scientist. Drawing on his expertise, Berger will be testing its match bullets to establish more precise drag figures. So, you may see the stated BCs on your favorite Berger bullets changing a bit in the future, but those changes will be based on improved design analysis and testing.
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January 16th, 2009
For precision rifle shooters, Lapua brass is about as good as it gets. It is definitely the preferred cartridge brass for short-range benchrest, 600-yard benchrest, and F-Class competition. Jason visited the Lapua booth to find out what new products the Finnish manufacturer will offer in 2009. In the video below, Sales Manager Adam Braverman reviews Lapua’s new offerings.
Lapua Revives .222 Remington Line
The big news is the re-introduction of .222 Remington brass. In late 2008 we revealed that Lapua would resume production of .222 Rem brass, and now we’ve learned that Lapua will be producing .222 Rem loaded ammo as well. Notably, this new .222 Rem brass (and ammo) will be produced “in-house” by Lapua. We expect it will meet the same exacting standards as other Lapua match brass. The .222 brass will be available immediately, and you should soon find it in stock at Grafs.com.
NEW 300gr, .338 Scenar Bullet
Big bore shooters will be pleased to know that Lapua has introduced a new 300gr, .338-caliber Scenar match bullet. When launched from the .338 Lapua Magnum cartridge, the new GB528 300-grainer will stay supersonic past 1500 meters. And even at 1700 meters it still carries over 1000 Joules of energy. You won’t find the 300gr Scenar in a silver cardboard box, however. From now on, Lapua match bullets will arrive in durable blue plastic containers. That’s progress we guess.
New BC Data Available for QuickTARGET
The ballistic coefficient of the new 300-grainers, as well as most other Lapua bullets, can now be inputed directly into the QuickTARGET ballistics program. BC values for Lapua bullets were confirmed with actual “real world” testing using Doppler radar.
No luck this year for .260 Rem and Short Mag Shooters
Despite persistent rumors, we won’t be seeing .260 brass or Short Mag brass from Lapua this season — though Lapua hasn’t ruled this out for some time in the future. Lapua does invite input from shooters, particular on the Short Magnum question. If Lapua feels there is adequate demand, it might (we stress might) consider production of a short mag. The question is “which short magnum?” The WSM family certainly has been more widely adopted thus far, but for match shooters, particularly 7mm shooters, the Remington SAUM may be a more efficient (and potentially more accurate) case. Right now, Lapua is leaning to the WSM, according to our sources.
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August 30th, 2008
One of the great things about our Shooters’ Forum is that many uniquely talented shooters share their knowledge and test findings. One of those experts is “bsl135″ aka Bryan Litz. Bryan is no ordinary “weekend warrior”. He graduated from Penn State with a degree in Aerospace Engineering. He then began a career as a missile design engineer at Wright-Patterson Air Force Base. He has written many ballistics programs and technical papers dealing with long-range flight dynamics of projectiles. Bryan is also a superb long-range shooter, holding an NRA High Master Classification. At this year’s NRA National Championships at Camp Perry, Bryan beat 258 other competitors to win the Palma Individual Trophy Match. Bryan shot a remarkable 450/26x, not dropping a single point.
Breaking News: Just today, Bryan won the Ohio State Midrange Championship, an iron sights event with 15 shots each at 300, 500, and 600 yards. Bryan shot a spectacular 450/39X. Again, Bryan didn’t drop a point and his X-count would make this a new National Record, pending certification. Congrats Bryan!
Bryan also has his own website with a number of authoritative articles. Topics include: Bullet Design, Meplat Trimming, Gyroscopic and Coreolis Drift, Palma Bullet Analysis, How Ballistics Programs Work, and Ballistic Coefficient Testing. CLICK HERE to visit BRYAN LITZ Website.
7mm Bullet BC Testing — Evaluating the Numbers
Bryan does a lot of testing for bullet-makers, evaluating the performance of various bullet types. One thing he has observed is that manufacturers’ published BCs may vary considerably even for two bullet designs that appear to be nearly identical. In our Forum, Bryan offered this interesting analysis of the 7mm Berger 180gr VLD and the similar 7mm JLK 180gr VLD:
“I’ve developed a repeatable procedure for test firing bullets to determine ballistic coefficient. If you get Precision Shooting Magazine, the March issue has one of my articles about test firing the Berger .30 cal 155gr VLD. Long story short, my test procedure uses acoustic sensors in 200-yard increments to measure time of flight out to 600 or 1000 yards. My BC measurements are repeatable to within +/- 2%, usually within +/- 1%.
I have tested several 7mm bullets. Of particular interest are the Berger 180gr and JLK 180gr bullets. If you look at these bullets side by side, it’s hard to tell a difference between them. I believe the JLK bullet dies were made from the same set of prints as the Berger VLD (Design by Bill Davis of Tioga Engineering). So … why would these bullets have different [published] BCs? They’re the same weight and the same basic shape [with very minor differences in OAL and bearing surface length]. This is just the kind of smoke and mirrors that makes shooters think there is something mysterious about BCs and exterior ballistics that’s beyond the realm of human understanding. I was pleased with the results of my testing of these two bullets: the BC is virtually the same, as expected. All is right with the world.”
Drag Models — G7 is better than G1 for long-range Bullets
Most ballistics programs use the default G1 drag model. Bryan believes the G7 standard is preferrable for long-range, low-drag bullets: “Part of the reason there is so much ‘slop’ in advertised BCs is because they’re referenced to the G1 standard which is very speed sensitive. The G7 standard is more appropriate for long range bullets. Here are the results of my testing for these two bullets:
G1 BCs, averaged between 1500 fps and 3000 fps:
Berger 180 VLD: 0.659 lb/in²
JLK 180: 0.645 lb/in²
The reason the BC for the JLK is less is mostly because the meplat was significantly larger on the particular lot that I tested (0.075″ vs 0.059″; see attached drawings).
For bullets like these, it’s much better to use the G7 standard. The following BCs are referenced to the G7 standard, and are constant for all speeds.
G7 BCs:
Berger 180 VLD: 0.337 lb/in²
JLK 180: 0.330 lb/in²
Many modern ballistics programs, including the free online JBM ballistics program, are able to use BCs referenced to G7 standards. When available, these BCs are more appropriate for long range bullets.”
[Editor’s NOTE: BCs are normally reported simply as an 0.XXX number. The lb/in² tag applies to all BCs, but is commonly left off for simplicity.]
Effect of Bullet Pointing
Bryan has also tested the effect of pointing bullets. He’s determined that this does have a positive (if small) effect on ballistics. Bryan writes: “I have measured the Berger 180 VLD in both nominal and pointed meplat configurations. Pointing the meplat from 0.059″ to 0.039″ increases the G7 BC from 0.337 lb/in² to 0.344 lb/in². This results in less than 2″ difference in 1000-yard wind drift (10 mph 90°). The improvement is small, perhaps negligible for standard decimal prone targets with large scoring rings. The improvement is more significant for F-Class targets with smaller scoring rings. That being said, I do point my own Berger 180 VLDs that I shoot in prone competition. It’s fast, easy, doesn’t hurt anything, and every little bit helps.”
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May 10th, 2008
The Barnes Triple-Shock X-Bullet has long been considered one of the best hunting bullets for game hunters. The all-copper construction provides excellent expansion and very high weight retention. The absence of a lead core means this bullet is also legal in areas (such as parts of California) where lead-containing bullets are banned.
The big innovation in the new Tipped TSX bullet is the addition of a polymer tip. The tip increases the bullet’s Ballistic Coefficient (BC). Additionally, polymer-tipped bullets show less bullet-to-bullet variance in BC than do conventional bullets. More uniform BC can make your point of impact at long range more predictable, shot after shot.
The TSX bullet, like the previous Triple-Shock, has grooves, or “drive bands”, formed in the outer casing. This effectively reduces the bearing surface. The use of drive bands is a proven bullet technology that can reduce friction and barrel copper fouling, while allowing higher velocities for a given bullet weight.
The TSX bullet is available in these calibers and weights:
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December 7th, 2007
Sinclair Int’l now carries the Bullet Test Tube. This unique bullet-testing system uses cardboard tubes filled with a reusable plastic-like test medium. Field & Stream named the Bullet Test Tube a “Best of the Best” product in 2006. According to Sinclair, this system is the only bullet-testing medium that lets you measure wound cavity in detail including volume. To reuse the testing medium, simply melt the expansion material in a standard 1.5 gallon crock-pot and pour it into a replacement target mold.
If you wish to capture the bullet after it passes through the test medium, add the Xtender accessory which slips on the end. This allows hunters to examine bullet integrity as well as wound cavity. Sinclair Int’l prices the Bullet Test Tube at $61.25, while the Xtender is an additional $57.60.
For more information, read this Test Tube FAQ, or Click the screenshot below to watch a QuickTime Video that demonstrates the whole process.
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