As far as we can tell, the first-ever formal benchrest shooting match took place in 1944 at the Tacoma Rifle & Revolver Club in Tacoma, Washington. Known today as the “Sniper King Competition”, this is still a popular event, drawing top shooters from around the country.
Our friend Lou Murdica bested the competition this year to win the Sniper King competition and Benchrest shooting’s oldest trophy. Take a look at that target. That’s a TEN-Shot group at TWO hundred yards. That works out to 0.1299 MOA for ten shots. That’s might impressive…
We have to give Lou credit for his shooting skills and loading spectacularly accurate ammo. Lou was running a Kelbly action, Shilen Barrel, and March scope. He loaded 6mm Berger 65gr BT bullets driven by Accurate LT 30 powder.
Have you ever shot a smaller TEN-shot group, even at 100 yards? If so, tell us about that, by posting a comment below.
Forum member XmarksSpot has been shooting a wicked fast varmint cartridge that has broken the 5000-fps barrier using Berger 30gr varmint bullets. That’s some serious velocity! The parent case is a 6mmBR, which is then improved and necked down to .224 caliber. XmarksSpot reports:
Some people think 5000+ fps is mythical. Well just thought I’d let you guys know that I got 5239 fps a couple weeks ago shooting 30-grainers with my 224 McDonald, a wildcat cartridge based on an improved 6BR case necked down to 224. (This case is very similar to a 22 Dasher.) The bullet used is the 30gr Berger. (The 40s run fast too — about 4800 fps.) The rig is a Rem 700 with a 30″ Hart barrel. Below is the case before and after forming. As you can see it has a 40° shoulder and far more case capacity than a 22 BR (a 22 Dasher case holds about 41.0 grains H20). My most accurate loads are with 50-52gr bullets, with bugholes the norm at 4200 fps. The 40gr bullets will do 4800+ fps.
This 224 McDonald wildcat was originally developed by Charles McDonald. He has been developing and chambering custom cartridges for years. Editor’s Note: Many folks may not be aware of the little .224-caliber 30gr Berger varmint bullet, Berger item # 22301. This bullet is not on Berger’s current production list but some vendors may still have “old stock” inventory. The little 30-grainer has an 0.119 G1 BC and will work in 1:15″ or faster twist barrels. For more info, visit BergerBullets.com.
Many tactical shooters have adopted the .260 Remington as an alternative to the heavier-recoiling .308 Winchester. The .260 Rem has also performed well in the hands of long-range High Power shooters such as SSG Sherri Jo Gallagher, past National High Power Champion. The .260 Remington is basically the .308 Win necked down to .264 (6.5 mm) caliber. It can launch very high-BC 130-142 grain projectiles at impressive velocities. The ballistics of the .260 Rem allow it to shoot flatter, with less wind drift, than typical .308 Win loads.
For fans of the .260 Remington, very high-quality factory ammo is now available. ABM Ammo, a division of Berger Bullets just announced that it will produce two varieties of .260 Remington ammo.
ABM’s 260 Remington 140gr Berger Match Hybrid Target ammo is designed for class-leading ballistic and superior accuracy. Using the highest-BC 6.5 mm caliber bullet offered by Berger, the 140gr Hybrid, this load features less wind deflection and more energy on target than the competition. ABM claims that this Match Hybrid ammo is “unrivaled as a long-range 260 Remington factory ammo option.” Since it pushes a higher-BC bullet than other .260 Rem factory ammo, we’d have to agree with that statement.
Performance based on a 26″ barrel and sea level conditions.
Mission Ready .260 Rem OTM Tactical Load for Mag-Fed Rifles
ABM Ammo also offers .260 Rem factory ammo loaded with the NEW 130gr AR Hybrid bullet. The .260 Rem 130gr Berger Match AR Hybrid OTM Tactical load is optimized for the AR-10 platform or any magazine-fed rifle. Berger’s 130gr AR Hybrid bullet offers a 0.290 G7 BC. That’s very close to the 0.317 BC of the longer 140gr Hybrid. This, combined with a 2847 FPS muzzle velocity, provides excellent performance in a shorter COAL that feeds perfectly from box magazines.
In fact, if you run the ballistics (using JBM) using ABM’s published MVs, you’ll find that you give up nothing with the shorter bullet. At 600 yards, the 130gr “Mission Ready” load has 78.8″ (12.5 MOA) of drop. By comparison, the “Match Ready” load with 140-grainers has 80.3″ (12.8) MOA of drop at 600 Yards (That’s not a mistake — the smaller bullet has LESS drop because it has a higher MV to start.) At 1000 yards, the “Mission Ready” load is virtually identical to the “Match Ready” load: The 130gr ammo has 304.6″ (29.1 MOA) of drop at 1000 vs 303.4″ (29.0 MOA) for the 140gr ammo at the same distance. (These calculations are based on standard conditions at sea level, with ABM supplied MVs.)
Because the ballistics are so close, you may want to try both loads in your .260 Rem rifle, even if you single-load and are not restricted by mag length. Some barrels may have a preference for one bullet over the other.
Product Tip from EdLongRange. We welcome reader submissions.
ABM Ammo, a division of Berger Bullets, has introduced new, high performance .308 Winchester factory ammunition, loaded with the high-BC, 185gr Berger Juggernauts. The long-loaded “Match Ready” version of this ammo is designed for Palma (Full-bore) and F-TR shooters. A “Mission Ready” version, loaded shorter to mag length, is designed for tactical and military applications. These two new offerings should “raise the bar” for long-range performance with factory .308 Win ammo.
Offering a high Ballistic Coefficient (0.560 G1, 0.283 G7), the 185-grain .308-caliber Juggernaut bullet is designed to remain stable even in the transonic zone. This way it offers good performance at extended distances, contributing to higher hit percentages at longer ranges.
Berger Twist-Rate Stability Calculator
On the updated Berger Bullets website you’ll find a handy Twist-Rate Stability Calculator that predicts your gyroscopic stability factor (SG) based on mulitiple variables: velocity, bullet length, bullet weight, barrel twist rate, ambient temperature, and altitude. This very cool tool tells you if your chosen bullet will really stabilize in your barrel.
LIVE DEMO BELOW — Just enter values in the data boxes and click “Calculate SG”.
Berger Bullets has just announced a new 6.5 mm (.264 caliber) 130gr Hybrid projectile. Optimized for magazine-length seating (and AR10-friendly), the new 130gr bullets should be ideal for tactical comps and the PRS series. We expect this new bullet to work great when loaded in modern mid-size cartridges such as the 6.5×47 Lapua and 6.5 Creedmoor. Berger’s new 6.5mm 130gr Match AR Hybrid OTM Tactical bullet (could Berger come up with a longer name?) will soon be released to the public. Berger says this new 130-grainer is the first of many new bullet designs to be introduced in the next few years. Here is a run-down on the new bullet from its designer, Bryan Litz of Applied Ballistics.
NEW 130gr Hybrid — Behind the Design
by Bryan Litz, Berger Chief Ballistician
Intelligent bullet design and selection begins with an understanding of application constraints. For bullets that will be used in unlimited rifles, there are few constraints and performance can truly be maximized. However, many shooting applications have realistic constraints such as magazine feeding of loaded rounds. In constrained applications, you need to ask the question: “What’s the best bullet that will work within the constraints of my shooting application?”
The new Berger 6.5mm 130 grain AR Hybrid OTM Tactical bullet is specifically optimized for maximum performance in magazine-length ammo.
6.5mm cartridges are the second most common cartridges used by top shooters in many of the Precision Rifle Series (PRS) matches, with 6mm being the most common. These kinds of tactical matches all have stages that require repeating rifles — either AR-10 platforms or bolt guns — so magazine feeding is a must. Recognizing that Berger did not have an option that was truly optimized for this particular application, we went to work and the latest 6.5mm Hybrid is the result.
SUMMARY
The new Berger 6.5mm 130 grain AR Hybrid OTM Tactical bullet is specifically optimized for use in loaded ammo with COAL constraints for magazine feeding. This bullet maximizes overall performance through BC as well as achievable muzzle velocity in mid-capacity 6.5mm cartridges fed from AR-length magazines.
What makes this bullet optimal for magazine length ammo? To start with, the nose of the bullet is constrained in length so that when it’s loaded to mag length in 6.5mm cartridges such as the 6.5mm Creedmoor, 260 Remington and 6.5×47 Lapua, the nose of the bullet won’t be pushed below the case mouth. This can be an issue with some of the heavier 6.5mm bullets like the 140s. Furthermore, the hybrid ogive design is not sensitive to jump distance like some other designs such as the VLD.
Another consideration of length-constrained ammo is how much of the bullet is pushed down into the case. The inside of the case is for powder, and the more space you take up with bullet, the less powder you can fit in. Less powder means less total energy available, and muzzle velocity is depressed. A bullet weight of 130 grains is an optimal balance between external ballistic performance (BC) and internal case capacity considerations which translate into muzzle velocity. Further to this objective, the AR Hybrid has a minimal air gap in the front of the nose, which allows the bullet to have an even shorter OAL. When dealing with length-constrained designs, you need to pack as much bullet into as little length as possible< to optimize overall performance. Another advantage of making the bullet shorter is that stability, including transonic stability, is improved.
Although this design is length-constrained, the combination of a hybrid ogive and 7 degree Boat Tail produce a very respectable G7 form factor of 0.920 which is within 1% of the popular 6mm 105 grain Hybrid. See below for full live fire ballistic performance data.
The 6.5mm 130 grain AR Hybrid will be barely stable from a 1:9″ twist, and reaches full stability from a 1:8″ twist which is common for many 6.5mm rifles. Visit the Berger Bullets twist rate calculator to get more detailed stability information on your specific barrel twist, muzzle velocity and environment.
Cartridge Selection for Magazine Length Constraint — Advanced Analysis
The trend to smaller calibers in magazine-fed rifles is happening for a very good reason. For a .308 Winchester round, you only have 2.37 calibers of nose length available for the bullet to protrude from the case. Such a short nose will have relatively high drag for the caliber. By contrast, smaller calibers such as 6.5mm and 6mm have proportionally more length available for the nose to protrude from the case and still fit in the same COAL constraint. Proportionally longer noses mean lower drag. Proportionally longer bullets mean higher sectional density. Combine an elevated sectional density with lower drag, and you get higher BC bullets. For example, consider a 175 grain .30 caliber bullet commonly used in .308 Winchester M118LR-type ammo. These 175 grain bullets have G7 BCs in the neighborhood of .243 to .260. Neck the .308 down to 6.5mm (260 Remington) or 6mm (.243 Winchester) and now look at the BCs of the bullets available in these calibers which work within the same magazine length constraint. The 6.5mm 130 grain AR Hybrid has a G7 BC of 0.290, and the 6mm 105 grain Hybrid has a G7 BC of 0.278 — both of which are higher than the .30 cal 175 grain bullet BC. Furthermore, you get hundreds of feet per second more velocity with the necked-down cartridges as well.
All of the above translates into higher hit percentage. See the caliber comparison chart below* which is an excerpt taken from the book: Modern Advancements in Long Range Shooting which addresses this and many other topics in even more detail.
*The Weapon Employment Zone (WEZ) analysis shown above is for a 1000-yard shot on a standard IPSC silhouette in an uncertain environment having: +/- 2 mph wind, +/- 1 yard range, Muzzle Velocity SD of 10 fps, and a rifle shooting 1 MOA groups.
Ever wondered how a modern, jacketed bullet is made? Thanks to Berger Bullets, here’s a short video clip that shows how bullets are crafted. In this short sequence filmed at Berger’s factory, you can see machinery that forms the jacket, inserts the core, and then forms the final shape.
Walt Berger, a living legend in the benchrest world, was honored this past weekend at the Ben Avery Range outside Phoenix, AZ. At the start of the 2015 Cactus Classic Benchrest match, a “surprise” ceremony was held. Berger President Eric Stecker announced to the crowd that the 100/200-yard benchrest facility was being dedicated to Walt Berger, founder of Berger Bullets. Walt was genuinely surprised and moved by the special ceremony, which featured a color guard, and a fly-over. In the photo above, Walt is flanked by his grandson David Hamilton (left) and Eric Stecker (right).
As part of the range dedication ceremony, four vintage, WWII-era Warbirds flew over the range in diamond formation, streaming red, white, and blue smoke.
Shortly after the ceremony, the competitors got down to business…
More Spin, Less Drag
In this article, we look at how twist rate and stability affect the Ballistic Coefficient (BC) of a bullet. Again, this topic is covered in detail in the Modern Advancements book. Through our testing, we’ve learned that adequate spin-stabilization is important to achieving the best BC (and lowest drag). In other words, if you don’t spin your bullets fast enough (with sufficient twist rate), the BC of your bullets may be less than optimal. That means, in practical terms, that your bullets drop more quickly and deflect more in the wind (other factors being equal). Spin your bullets faster, and you can optimize your BC for best performance.
Any test that’s designed to study BC effects has to be carefully controlled in the sense that the variables are isolated. To this end, barrels were ordered from a single barrel smith, chambered and headspaced to the same rifle, with the only difference being the twist rate of the barrels. In this test, 3 pairs of barrels were used. In .224 caliber, 1:9” and 1:7” twist. In .243 caliber it was 1:10” and 1:8”, and in .30 caliber it was 1:12” and 1:10”. Other than the twist rates, each pair of barrels was identical in length, contour, and had similar round counts. Here is a barrel rack at the Applied Ballistics Lab:
Applied Ballistics used multiple barrels to study how twist rate affects BC.
“The Modern Advancements series is basically a journal of the ongoing R&D efforts of the Applied Ballistics Laboratory. The goal of the series is to share what we’re learning about ballistics so others can benefit.” –Bryan Litz
Barrel twist rate along with velocity, atmospherics, and bullet design all combine to result in a Gyroscopic Stability Factor (SG). It’s the SG that actually correlates to BC. The testing revealed that if you get SG above 1.5, the BC may improve slightly with faster twist (higher SG), but it’s very difficult to see. However, BC drops off very quickly for SGs below 1.5. This can be seen in the figure below from Modern Advancements in Long Range Shooting.
The chart shows that when the Gyroscopic Stability Factor (SG) is above 1.5, BC is mostly constant. But if SG falls below 1.5, BC drops off dramatically.
Note that the BC drops by about 3% for every 0.1 that SG falls below 1.5. The data supports a correlation coefficient of 0.87 for this relationship. That means the 3% per 0.1 unit of SG is an accurate trend, but isn’t necessarily exact for every scenario.
It’s a common assumption that if a shooter is seeing great groups and round holes, that he’s seeing the full potential BC of the bullets. These tests did not support that assumption. It’s quite common to shoot very tight groups and have round bullet holes while your BC is compromised by as much as 10% or more. This is probably the most practical and important take-away from this test.
To calculate the SG of your bullets in your rifle, visit the Berger Bullets online stability calculator. This FREE calculator will show you the SG of your bullets, as well as indicate if your BC will be compromised (and by how much) if the SG is below 1.5. With the stated twist rate of your barrel, if your selected bullet shows an SG of 1.5 (or less), the calculator will suggest alternate bullets that will fully stabilize in your rifle. This valuable online resource is based directly on live fire testing. You can use the SG Calculator for free on the web — you don’t need to download software.
Learn More About SG and BC This article is just a brief overview of the interrelated subjects of twist rate, Gyroscopic Stability, and BC. The coverage of twist rates in Modern Advancements in Long-Range Shooting is more detailed, with multiple live fire tests.
Other chapters in the book’s twist rate section include: · Stability and Drag – Supersonic
· Stability and Drag – Transonic
· Spin Rate Decay
· Effect of Twist rate on Precision
Other sections of the book include: Modern Rifles, Scopes, and Bullets as well as Advancements in Predictive Modeling. This book is sold through the Applied Ballistics online store. Modern Advancements in Long Range Shooting is also available in eBook format in the Amazon Kindle store.
At the 2015 Berger Southwest Nationals, Forum member Erik Cortina cornered Bryan Litz of Applied Ballistics. Erik, the F-Open winner in the 600-yard Mid-Range match, was curious about bullet sorting. Knowing that bullets can be sorted by many different criteria (e.g. weight, overall length, base to ogive length, actual bearing surface length etc.) Erik asked Bryan to specify the most important dimension to consider when sorting. Bryan recommended sorting by “Base to Ogive”. Litz noted that: “Sorting by overall length can be misleading because of the nature of the open-tip match bullet. You might get a bullet that measures longer because it has a jagged [tip], but that bullet might not fly any different. But measuring base to ogive might indicate that the bullet is formed differently — basically it’s a higher resolution measurement….”
Ballistics Q & A in Shooter’s Forum
Got more questions about bullets? Our Shooters’ Forum has a special area for Bullets & Ballistics topics. There you can get your own questions about bullets and ballistics answered by Bryan Litz and other experts from Applied Ballistics.
Proportionally longer noses mean lower drag. Proportionally longer bullets mean higher sectional density. Combine an elevated sectional density with lower drag, and you get higher BC bullets. For example, consider a 175 grain .30 caliber bullet commonly used in .308 Winchester M118LR-type ammo. These 175 grain bullets have G7 BCs in the neighborhood of .243 to .260. Neck the .308 down to 6.5mm (260 Remington) or 6mm (.243 Winchester) and now look at the BCs of the bullets available in these calibers which work within the same magazine length constraint. The 6.5mm 130 grain AR Hybrid has a G7 BC of 0.290, and the 6mm 105 grain Hybrid has a G7 BC of 0.278 — both of which are higher than the .30 cal 175 grain bullet BC. Furthermore, you get hundreds of feet per second more velocity with the necked-down cartridges as well.
