Berger Twist-Rate Stability Calculator On the 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 cool tool tells you if your chosen bullet will really stabilize in your barrel.
How to Use Berger’s Twist Rate Calculator
Using the Twist Rate Calculator is simple. Just enter the bullet DIAMETER (e.g. .264), bullet WEIGHT (in grains), and bullet overall LENGTH (in inches). On its website, Berger conveniently provides this info for all its bullet types. For other brands, we suggest you weigh three examples of your chosen bullet, and also measure the length on three samples. Then use the average weight and length of the three. To calculate bullet stability, simply enter your bullet data (along with observed Muzzle Velocity, outside Temperature, and Altitude) and click “Calculate SG”. Try different twist rate numbers (and recalculate) until you get an SG value of 1.4 (or higher).
Gyroscopic Stability (SG) and Twist Rate
Berger’s Twist Rate Calculator provides a predicted stability value called “SG” (for “Gyroscopic Stability”). This indicates the Gyroscopic Stability applied to the bullet by spin. This number is derived from the basic equation: SG = (rigidity of the spinning mass)/(overturning aerodynamic torque).
If you have an SG under 1.0, your bullet is predicted not to stabilize. If you have between 1.0 and 1.1 SG, your bullet may or may not stabilize. If you have an SG greater than 1.1, your bullet should stabilize under optimal conditions, but stabilization might not be adequate when temperature, altitude, or other variables are less-than-optimal. That’s why Berger normally recommends at least 1.5 SG to get out of the “Marginal Stability” zone.
In his book Applied Ballistics For Long-Range Shooting (3rd Ed.), Bryan Litz (Berger Ballistician) recommends at least a 1.4 SG rating when selecting a barrel twist for a particular bullet. This gives you a safety margin for shooting under various conditions, such as higher or lower altitudes or temperatures.
Story idea from EdLongrange. We welcome reader submissions.
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Creedmoor Sports has released a series of helpful “how-to” videos in its new InfoZone web page. In the latest InfoZone video Bill Gravatt shows how to seat bullets using L.E. Wilson Hand Dies and an Arbor Press. The basic process is simple, particularly with a micrometer-top seating die. That makes it easy to adjust and set seating depth. Before you start seating bullets, you want to adjust the height of the arbor so the stroke is appropriate to the height of your die.
Bill Gravatt Shows How to Use Hand Seating Dies — Creedmoor INFOZONE
ARBOR PRESS TECHNIQUE: When using an arbor press, smooth is good. You don’t want to slam the handle down quickly. Try to repeat the same motion each time. You can also experiment by seating the bullet part way, then rotate the cartridge (in the die) and do the final seating with a second stroke. If your arbor press has a force gauge, note both the max value of the gauge needle and how it moves as you seat the bullet. If the needle spikes too rapidly, or bounces back and forth irregularly, set that cartridge aside and/or mark it. You could have neck tension issue with that case or some other fault. You might even have a bad bullet. That’s rare, but can happen. The key to success is moving the press arm in a smooth motion every time, maintaining the same down-pressure with each cartridge.
Here Bill Gravatt Offers a Simple Tip for Adjusting Wilson Seating Dies
One of our Forum readers asked “How can I get a custom in-line seater for my new rifle?”. First, we would say that, if you are not shooting an unusual Wildcat, check first to see if L.E. Wilson makes a stainless Micrometer Seater Die for your rifle. These dies are a joy to use, and we’ve found the fit to be exceptionally good with many calibers. Typically priced from $95-$115, Wilson stainless micrometer-top seaters are available for dozens of cartridge types: .204 Ruger, 20 BR, .222 Rem, .223 Rem, 22 PPC, 22 BR, .22-250, .223 WSSM, 6 PPC, 6mmBR, 6XC, 243 Win, .243 WSSM, 25 WSSM, 6.5×47 Lapua, 6.5 Creedmoor, 6.5-284, 26 Nosler, .270 WSM, 7mm-08, .284 Win, 28 Nosler, 7mm RUM, 30 BR, 30 IHMSA, .308 Win, .300 WinMag, .338 Edge (and MORE).
If you do want a custom seater die, the process is relatively simple. Purchase a die blank from Wilson and have your gunsmith run the chambering reamer in. Forum member Gunamonth explains: “I start with a Wilson seating die blank. They’re available from Sinclair and other vendors. Just run the reamer in. For some of my rifles, where I wanted the stainless die with the micrometer adjustment, I bought a smaller die and had the smith ream it with the chamber reamer. That’s how I had my 6 Dasher and 6mm AI seaters made. With the Dasher I stared with a 6mmBR Micrometer die.”
SEATER STEM TIP: If, on your seated bullets, you are seeing a sharp line around the jacket near the ogive, you may want to smooth out the leading edge of the Wilson seater stem (see above left). Do this by putting a little lapping compound on one bullet and manually spin this around in the stem. Without much effort you’ll have a smooth bullet/stem interface.
Micrometer Top Add-on
We really like micrometer tops on a seating die. But what if Wilson doesn’t make a micrometer top seater for your chambering? Don’t despair, Brownells sells a $39.99 Sinclair Micrometer Top that can be added to Wilson standard seaters or to a custom seater die made from a Wilson die blank.
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Berger Twist-Rate Stability Calculator On the 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 cool tool tells you if your chosen bullet will really stabilize in your barrel.
How to Use Berger’s Twist Rate Calculator
Using the Twist Rate Calculator is simple. Just enter the bullet DIAMETER (e.g. .264), bullet WEIGHT (in grains), and bullet overall LENGTH (in inches). On its website, Berger conveniently provides this info for all its bullet types. For other brands, we suggest you weigh three examples of your chosen bullet, and also measure the length on three samples. Then use the average weight and length of the three. To calculate bullet stability, simply enter your bullet data (along with observed Muzzle Velocity, outside Temperature, and Altitude) and click “Calculate SG”. Try different twist rate numbers (and recalculate) until you get an SG value of 1.4 (or higher).
Gyroscopic Stability (SG) and Twist Rate
Berger’s Twist Rate Calculator provides a predicted stability value called “SG” (for “Gyroscopic Stability”). This indicates the Gyroscopic Stability applied to the bullet by spin. This number is derived from the basic equation: SG = (rigidity of the spinning mass)/(overturning aerodynamic torque).
If you have an SG under 1.0, your bullet is predicted not to stabilize. If you have between 1.0 and 1.1 SG, your bullet may or may not stabilize. If you have an SG greater than 1.1, your bullet should stabilize under optimal conditions, but stabilization might not be adequate when temperature, altitude, or other variables are less-than-optimal. That’s why Berger normally recommends at least 1.5 SG to get out of the “Marginal Stability” zone.
In his book Applied Ballistics For Long-Range Shooting (3rd Ed.), Bryan Litz (Berger Ballistician) recommends at least a 1.4 SG rating when selecting a barrel twist for a particular bullet. This gives you a safety margin for shooting under various conditions, such as higher or lower altitudes or temperatures.
Story idea from EdLongrange. We welcome reader submissions.
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Creedmoor Sports has released a series of helpful “how-to” videos in its new InfoZone web page. In the latest InfoZone video Bill Gravatt shows how to seat bullets using L.E. Wilson Hand Dies and an Arbor Press. The basic process is simple, particularly with a micrometer-top seating die. That makes it easy to adjust and set seating depth. Before you start seating bullets, you want to adjust the height of the arbor so the stroke is appropriate to the height of your die.
Bill Gravatt Shows How to Use Hand Seating Dies — Creedmoor INFOZONE
ARBOR PRESS TECHNIQUE: When using an arbor press, smooth is good. You don’t want to slam the handle down quickly. Try to repeat the same motion each time. You can also experiment by seating the bullet part way, then rotate the cartridge (in the die) and do the final seating with a second stroke. If your arbor press has a force gauge, note both the max value of the gauge needle and how it moves as you seat the bullet. If the needle spikes too rapidly, or bounces back and forth irregularly, set that cartridge aside and/or mark it. You could have neck tension issue with that case or some other fault. You might even have a bad bullet. That’s rare, but can happen. The key to success is moving the press arm in a smooth motion every time, maintaining the same down-pressure with each cartridge.
Here Bill Gravatt Offers a Simple Tip for Adjusting Wilson Seating Dies
One of our Forum readers asked “How can I get a custom in-line seater for my new rifle?”. First, we would say that, if you are not shooting an unusual Wildcat, check first to see if L.E. Wilson makes a stainless Micrometer Seater Die for your rifle. These dies are a joy to use, and we’ve found the fit to be exceptionally good with many calibers. Typically priced from $90-$100, Wilson stainless micrometer-top seaters are available for dozens of cartridge types: .204 Ruger, 20 BR, .222 Rem, .223 Rem, 22 PPC, 22 BR, .22-250, .223 WSSM, 6 PPC, 6mmBR, 6XC, 243 Win, .243 WSSM, 25 WSSM, 6.5×47 Lapua, 6.5 Creedmoor, 6.5-284, 26 Nosler, .270 WSM, 7mm-08, .284 Win, 28 Nosler, 7mm RUM, 30 BR, 30 IHMSA, .308 Win, .300 WinMag, .338 Edge (and MORE).
If you do want a custom seater die, the process is relatively simple. Purchase a die blank from Wilson and have your gunsmith run the chambering reamer in. Forum member Gunamonth explains: “I start with a Wilson seating die blank. They’re available from Sinclair and other vendors. Just run the reamer in. For some of my rifles, where I wanted the stainless die with the micrometer adjustment, I bought a smaller die and had the smith ream it with the chamber reamer. That’s how I had my 6 Dasher and 6mm AI seaters made. With the Dasher I stared with a 6mmBR Micrometer die.”
SEATER STEM TIP: If, on your seated bullets, you are seeing a sharp line around the jacket near the ogive, you may want to smooth out the leading edge of the Wilson seater stem (see above left). Do this by putting a little lapping compound on one bullet and manually spin this around in the stem. Without much effort you’ll have a smooth bullet/stem interface.
Micrometer Top Add-on
We really like micrometer tops on a seating die. But what if Wilson doesn’t make a micrometer top seater for your chambering? Don’t despair, Brownells sells a $39.99 Sinclair Micrometer Top that can be added to Wilson standard seaters or to a custom seater die made from a Wilson die blank.
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Capstone is a respected company that represents world-class ammunition, powder, and component manufacturers Berger, Lapua, Vihtavuori, and SK. At SHOT Show 2022, Capstone showcased new products from all these brands. Here are summaries of the new-for-2022 products from Lapua and SK.
New Lapua Cartridge Brass:
6.5 PRC, .284 Win, .300 PRC, .300 Win Mag
Lapua cartridge brass sets the standard by which quality brass is measured. You will see Lapua brass used by top competitors for all accuracy-oriented disciplines: Benchrest for Score, Benchrest for Group, 1000-Yard Benchrest, F-Class (Open and F-TR), Palma, Service Rifle, Silhouette. And Lapua brass is also favored by varmint hunters who load their own ammo. In 2021 and 2022 Lapua has rolled out new types of top-grade cartrige barss. New offerings available now for 6.5 PRC, .284 Winchester, .300 PRC, and .300 Winchester Magnum. All are available and shipping now.
New Lapua Centerfire Match Ammunition
Lapua produces some of the finest, most accurate factory-loaded centerfire ammunition in the world. We have shot Lapua 90gr 6mmBR ammo that produced verified groups well under quarter-MOA. that’s remarkable for factory-loaded ammo that has not been tuned for a particular rifle. For 2022, Lapua has added three new match loads that promise great consistency and accuracy. For 2022, Lapua has added 6.5 Creedmoor 136 Grain Scenar-L, .260 Remington 136 Grain Scenar-L, and .300 Winchester Magnum 185 Grain Scenar OTM, to Lapua’s highly successful Scenar Match Target ammunition line.
SK High-Velocity Match Rimfire Ammunitions
SK is owned by the same parent company as Lapua. SK now offers an extremely accurate, High-Velocity round. For 2022 SK will offer High-Velocity Match .22 LR ammunition. This new SK ammo pushes a 40gr round-nose projectile at a very fast 1,263 FPS muzzle velocity. This high-velocity SK ammunition should work well for PRS/NRL22 matches and long-range rimfire events, some of which have targets out to 300 meters. The new SK High-Velocity Match ammo employs a proprietary clean-burning and high-energy propellant for reliable function in all platforms — shot after shot.
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Capstone is a respected company that represents world-class ammunition, powder, and component manufacturers Berger, Lapua, Vihtavuori, and SK. At SHOT Show 2022, Capstone showcased new products from all these brands. Here are summaries of new products from Lapua and SK. We will follow with new Berger offerings next week.
New Lapua Centerfire Match Ammunition for 2022
Lapua produces some of the finest, most accurate factory-loaded centerfire ammunition in the world. We have shot Lapua 90gr 6mmBR ammo that produced verified groups well under quarter-MOA. For 2022, Lapua has added three new match loads that promise great consistency and accuracy. For 2022, Lapua has added 6.5 Creedmoor 136 Grain Scenar-L, .260 Remington 136 Grain Scenar-L, and .300 Winchester Magnum 185 Grain Scenar OTM, to Lapua’s highly successful Scenar Match Target ammunition line.
New Lapua Cartridge Brass — 6.5 PRC, .284 Win, .300 PRC, .300 Win Mag
Lapua cartridge brass sets the standard by which quality brass is measured. You will see Lapua brass used by top competitors for all accuracy-oriented disciplines: Benchrest for Score, Benchrest for Group, 1000-Yard Benchrest, F-Class (Open and F-TR), Palma, Service Rifle, Silhouette. And Lapua brass is also favored by varmint hunters who load their own ammo. In 2021 and 2022 Lapua has rolled out new types of top-grade cartrige barss. New offerings available now for 6.5 PRC, .284 Winchester, .300 PRC, and .300 Winchester Magnum. All are available and shipping now.
SK High-Velocity Match Rimfire Ammunitions
SK now offers an extremely accurate, High-Velocity round. For 2022 SK will offer High-Velocity Match .22 LR ammunition. This new SK ammo pushes a 40gr round-nose projectile at a very fast 1,263 FPS muzzle velocity. This high-velocity SK ammunition should work well for PRS/NRL22 matches and long-range rimfire events, some of which have targets out to 300 meters. The new SK High-Velocity Match ammo employs a proprietary clean-burning and high-energy propellant for reliable function in all platforms — shot after shot.
Coming Soon — New Berger Ammo and Bullets for 2022
Berger, another Capstone company, is offering new bullets and loaded ammunition for 2022. The new Berger offerings include Elite Hunter loaded ammunition for the 6.5 PRC and .300 PRC, plus new Berger .30 Caliber 245 Grain Long Range Hybrid Target (LRHT) Bullets. We’ll have a feature on these Berger products soon.
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A legend in the shooting community has passed. And we are all diminished. Walt Berger passed away on September 19, 2021. A great innovator, a great benchrest competitor (with many Hall of Fame points), and a great friend to countless shooters, Walt will be truly missed.
Berger Bullets announced yesterday: “It is with our deepest regrets that we announce the passing of Berger Bullets & Ammunition founder, Walter Berger. Walt passed peacefully on Sunday afternoon September 19th, 2021, surrounded by friends and family at the age of 92.
‘If a job’s worth doing, it’s worth doing right’, were words that Walt lived by. One could see it in how he treated friends and family, and in his impact on the shooting world. Walt’s legacy and dedication to quality is carried on by his grandson, David Hamilton, the Plant Manager of the Berger manufacturing facility in Mesa, Arizona. Walt’s philosophies and business practices are the guiding principles in our mission to ensure that products bearing the Berger name continue to be something Walt would be proud of. We celebrate his life and will do our best to live up to his example.”
Walt was a remarkable man who loved the sport of benchrest shooting. He was still competing at age 90+. Here he is in 2016 at the Cactus Classic in Arizona.
Many of our readers and Forum members knew Walt and shot with him at matches over the decades. Here are some of the expressions of sadness at his passing:
“Great man, he had a long run, and touched many lives.” — Boyd Allen
“A real gentleman and always there to help anyone that needed it. I’m blessed to have known him many years. RIP old Friend.” — Bill Shehane
“Now there is a man for ya! I remember talking to him and Eunice on the phone back in the 80s ordering some of their benchrest bullets. May God bless his family. Thank you Walt for the great bullets — I’ve watched them do some amazing things!” — Don Mild
“Walt was an iconic figure in accurate shooting for many many years. A gentleman in the game who traveled worldwide including Australia. He will be sorely missed. Our thoughts and prayers are with his friends and family. Rest assured men like Walt aren’t made any more. Thanks for everything Walt — your Australian friends will never forget you.” — Brad Ward
“When I first started chasing accuracy I used to buy bullets from Walt at his little shop on Camelback Road in Phoenix. He always had time to share his expertise and to help me. He and Eunice are together again, shooting at the big range in the sky where the weather is perfect with no wind.” — Doug Whitson
“My prayers go to David, Stacey, Eric, and the girls.
Walt was a truly special man and friend.” — Nancy Tompkins
“He was a Man of Legend. And Legends live forever.” — Ivan Lukashevych
About Walt Berger and Berger Bullets
Walt Berger shot competitive benchrest most of his adult life. Seeing that the bullets he could buy off-the-shelf were not up to his quality expectations, Walt decided that he could make better precision bullets than he could purchase. Walt started making his own bullets and proved their quality by winning competitions and eventually even earning his place in the Benchrest Shooters Hall of Fame. Other benchrest shooters saw his success and solicited him to make their bullets as well.
After years of crafting bullets by hand in his garage, Walt’s wife, Eunice, who was also a legend in benchrest competition, encouraged him to expand his hobby into a business. Together, they grew Berger into a large-scale precision bullet operation with exceptionally high quality standards.
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Creedmoor Sports has released a series of helpful “how-to” videos in its new InfoZone web page. In the latest InfoZone video Bill Gravatt shows how to seat bullets using L.E. Wilson Hand Dies and an Arbor Press. The basic process is simple, particularly with a micrometer-top seating die. That makes it easy to adjust and set seating depth. Before you start seating bullets, you want to adjust the height of the arbor so the stroke is appropriate to the height of your die.
Bill Gravatt Shows How to Use Hand Seating Dies — Creedmoor INFOZONE
ARBOR PRESS TECHNIQUE: When using an arbor press, smooth is good. You don’t want to slam the handle down quickly. Try to repeat the same motion each time. You can also experiment by seating the bullet part way, then rotate the cartridge (in the die) and do the final seating with a second stroke. If your arbor press has a force gauge, note both the max value of the gauge needle and how it moves as you seat the bullet. If the needle spikes too rapidly, or bounces back and forth irregularly, set that cartridge aside and/or mark it. You could have neck tension issue with that case or some other fault. You might even have a bad bullet. That’s rare, but can happen. The key to success is moving the press arm in a smooth motion every time, maintaining the same down-pressure with each cartridge.
Here Bill Gravatt Offers a Simple Tip for Adjusting Wilson Seating Dies
One of our Forum readers asked “How can I get a custom in-line seater for my new rifle?”. First, we would say that, if you are not shooting an unusual Wildcat, check first to see if L.E. Wilson makes a stainless Micrometer Seater Die for your rifle. These dies are a joy to use, and we’ve found the fit to be exceptionally good with many calibers. Typically priced from $90-$100, Wilson stainless micrometer-top seaters are available for dozens of cartridge types: .204 Ruger, 20 BR, .222 Rem, .223 Rem, 22 PPC, 22 BR, .22-250, .223 WSSM, 6 PPC, 6mmBR, 6XC, 243 Win, .243 WSSM, 25 WSSM, 6.5×47 Lapua, 6.5 Creedmoor, 6.5-284, 26 Nosler, .270 WSM, 7mm-08, .284 Win, 28 Nosler, 7mm RUM, 30 BR, 30 IHMSA, .308 Win, .300 WinMag, .338 Edge (and MORE).
If you do want a custom seater die, the process is relatively simple. Purchase a die blank from Wilson and have your gunsmith run the chambering reamer in. Forum member Gunamonth explains: “I start with a Wilson seating die blank. They’re available from Sinclair and other vendors. Just run the reamer in. For some of my rifles, where I wanted the stainless die with the micrometer adjustment, I bought a smaller die and had the smith ream it with the chamber reamer. That’s how I had my 6 Dasher and 6mm AI seaters made. With the Dasher I stared with a 6mmBR Micrometer die.”
SEATER STEM TIP: If, on your seated bullets, you are seeing a sharp line around the jacket near the ogive, you may want to smooth out the leading edge of the Wilson seater stem (see above left). Do this by putting a little lapping compound on one bullet and manually spin this around in the stem. Without much effort you’ll have a smooth bullet/stem interface.
Micrometer Top Add-on
We really like micrometer tops on a seating die. But what if Wilson doesn’t make a micrometer top seater for your chambering? Don’t despair, Sinclair Int’l sells a $39.99 micrometer top that can be added to Wilson standard seaters or to a custom seater die made from a Wilson die blank.
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We’re approaching winter — the perfect time to stock up on your propellants for next season. And now you can earn up to $5.00 per pound on your favorite Vihtavuori powders. Vihtavuori makes some great powders that have been used to set many records. With Vihtavuori’s Keep Your Cash Rebate, you can get up to $100 cash back on qualifying Vihtavuori powder purchases.
Vihtavuori $100 CONSUMER REBATE
This offer is valid on qualifying purchases made between November 1, 2019 and January 1, 2020. This applies to all sizes, 1-lb, 4-lb, and 8-lb. You can also mix and match powders to maximize your rebate. Pick up a Rebate Form from your favorite Vihtavuori retailer or download the PDF Form linked below. Then submit the form with your proof of purchase no later than January 31, 2020.
The 2019 Vihtavuori Rebate program is currently under way. For a limited time, earn $5.00 back per one-pound bottle, $10.00 per four-pound bottle, and $20.00 back per eight-pound bottle when you purchase Vihtavuori powders (maximum $100 rebate). Offer is valid on qualifying purchases made between November 1, 2019 and January 1, 2020. All rebate coupons must be received by January 31, 2020.
Good news for rimfire shooters! Lapua will open a new rimfire test center in Ohio in the fall of 2019. At this new facility, which will replicate Lapua’s current rimfire test center in Arizona, shooters can test various lots of Lapua rimfire ammunition to determine what shoots best in their firearms. The new location will have a full 100 meter testing tunnel, with electronic target readouts for both 50 meters and 100 meters. Customers have the option to send their rifles in for testing or schedule an onsite appointment to participate and view the test process.
“We’re taking our established practices and testing capabilities from our Mesa, AZ location to our new, second location in Ohio, offering customers state-of-the-art rimfire ammunition testing,” said Adam Braverman, Director of Sales and Marketing.
Patterned after the world-renowned Lapua Service Center in Schönebeck, Germany, the new Ohio facility will give shooters the chance to test various types and lots of rimfire ammunition, in their own firearms, under ideal conditions. Customers interested in performing ammo tests at either USA Lapua Rimfire Test locations (Arizona or Ohio), may call (480) 898-2731 or email rimfiretest@capstonepg.com .
Lapua announced: “Lapua … is proud to announce our second USA Lapua Rimfire Test Center at the Cardinal Shooting Center in Marengo, Ohio. The new Lapua Rimfire Test Center will offer competitive shooters and consumers alike the opportunity to match individual lots of Lapua ammunition to their match rifles and pistols. The new East Location will officially open in late Fall of 2019. All of the capabilities of the new test center will replicate our current Lapua Rimfire Test Center in Mesa, AZ.”
“We’re excited to partner with Lapua and bring this facility and test capabilities to our current and potential customers,” stated Jim Henderson, Director of Competitions at the Cardinal Shooting Center, “We feel this will help many consumers, as well as junior and collegiate teams…”
About Lapua
Lapua produces bullets, brass, and loaded rimfire and centerfire ammunition for civilian and professional use. Lapua is a part of the Capstone Precision Group, exclusive U.S. distributor for Berger, Lapua, Vihtavuori and SK-Rimfire products. For more information, visit Lapua.com.
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Berger Twist-Rate Stability Calculator
On the 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 cool tool tells you if your chosen bullet will really stabilize in your barrel.
How to Use Berger’s Twist Rate Calculator
Using the Twist Rate Calculator is simple. Just enter the bullet DIAMETER (e.g. .264), bullet WEIGHT (in grains), and bullet overall LENGTH (in inches). On its website, Berger conveniently provides this info for all its bullet types. For other brands, we suggest you weigh three examples of your chosen bullet, and also measure the length on three samples. Then use the average weight and length of the three. To calculate bullet stability, simply enter your bullet data (along with observed Muzzle Velocity, outside Temperature, and Altitude) and click “Calculate SG”. Try different twist rate numbers (and recalculate) until you get an SG value of 1.4 (or higher).
Gyroscopic Stability (SG) and Twist Rate
Berger’s Twist Rate Calculator provides a predicted stability value called “SG” (for “Gyroscopic Stability”). This indicates the Gyroscopic Stability applied to the bullet by spin. This number is derived from the basic equation: SG = (rigidity of the spinning mass)/(overturning aerodynamic torque).
If you have an SG under 1.0, your bullet is predicted not to stabilize. If you have between 1.0 and 1.1 SG, your bullet may or may not stabilize. If you have an SG greater than 1.1, your bullet should stabilize under optimal conditions, but stabilization might not be adequate when temperature, altitude, or other variables are less-than-optimal. That’s why Berger normally recommends at least 1.5 SG to get out of the “Marginal Stability” zone.
In his book Applied Ballistics For Long-Range Shooting, Bryan Litz (Berger Ballistician) recommends at least a 1.4 SG rating when selecting a barrel twist for a particular bullet. This gives you a safety margin for shooting under various conditions, such as higher or lower altitudes or temperatures.
Story idea from EdLongrange. We welcome reader submissions.
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This is BIG news for the Extreme Long Range (ELR) game. Berger Bullets will offer a line of SOLID bullets in .375 caliber. You read that right — these will be the first-ever large diameter Berger projectiles manufactured from a solid copper alloy. Most conventional bullets feature a jacket over a metal core, typically lead alloy. These new Berger solids are lathe-turned from solid copper alloy — shaped with precision into perfect aerodynamic profiles. The new Berger ELR solids boast a long, VLD shape with ultra-high Ballistic Coefficients. The new .375 caliber Berger ELR solids will be offered in two bullet weights: 379 grains and 407 grains.
The prototype 400gr version of this solid bullet was extensively tested at 2400 yards (above). It remained supersonic at that distance, a remarkable 1.36 miles. Berger will now offer two production versions, 379gr and 407gr, based on this successful prototype, further optimized. Here is Berger’s official release:
Berger Bullets proudly announces the New Extreme Long Range (ELR) Match Solid Projectile line, beginning with .375 caliber 379 grain and 407 grain offerings.
Extreme Long-Range shooting to distances of two miles and beyond has taken the firearms community by storm. With much of its roots developed from elite military sniper and Special Forces rifle training, ELR enthusiasts are utilizing highly innovative rifle and ammunition technology to engage targets at distances previously unheard of. Berger has taken the lead pioneering ELR, similar to how it’s dominated all other long-range rifle disciplines.
Berger Bullets chief ballistician Bryan Litz states: “Our new ELR Solid Match Bullets provide both competition shooters and Mil/LE forces a long-range solid projectile like no other. Its highly-optimized VLD ogive design and lathe-turned solid copper construction provide a ballistic advantage that is unmatched by any conventional-style bullet.”
Berger .375 Caliber Bullet is a Winner
Berger’s .375 caliber solid bullet design has already been proven in competition. At the 2018 World Longest Shot Challenge (WLSC), Team Applied Ballistics used the prototype .375 Cal ELR solid with great results. The new .375 caliber monolithic Berger bullet designed by Bryan Litz was used by the first and second place finishers in the “above .338 caliber” class. The prototype .375 Cal solid performed great, and the ultra-high BC was confirmed. READ WLSC Story HERE.
Advanced Doppler Radar was used to confirm Ballistics Data for the new Berger .375-Caliber Solids:
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On the 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 cool tool tells you if your chosen bullet will really stabilize in your barrel.
One of our Forum readers asked “How can I get a custom in-line seater for my new rifle?”. First, we would say that, if you are not shooting an unusual Wildcat, check first to see if 
New Lapua Cartridge Brass:
A legend in the shooting community has passed. And we are all diminished. Walt Berger passed away on September 19, 2021. A great innovator, a great benchrest competitor (with many Hall of Fame points), and a great friend to countless shooters, Walt will be truly missed.
