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July 13th, 2023
Over the past 12 months, this article was one of the TOP TEN most-read Daily Bulletin features. We’re reprising it today for those who may have missed it the first time. The above diagram comes from a TiborasurasRex YouTube Video comparing G1 and G7 BC models. CLICK HERE to watch the video.
 The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
 Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, believes the G7 standard is preferable 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’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
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, according to Bryan.
[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.]
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February 5th, 2023
Over the past 12 months, this article was one of the TOP 20 most-read Daily Bulletin features. We’re reprising it today for those who may have missed it the first time. The above diagram comes from a TiborasurasRex YouTube Video comparing G1 and G7 BC models. CLICK HERE to watch the video.
The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
 Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, 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’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
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, according to Bryan.
[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.]
This article is copyright 2023 AccurateShooter.com. No 3rd Party republication of this article is allowed without advance approval and payment of licensing fees.
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September 5th, 2019
Over the past 12 months, this article was one of the TOP TEN most-read Daily Bulletin features. We’re reprising it today for those who may have missed it the first time. The above diagram comes from a TiborasurasRex YouTube Video comparing G1 and G7 BC models. CLICK HERE to watch the video.
 The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferrable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, 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’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
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, according to Bryan.
[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.]
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September 12th, 2015
The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer to that is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferrable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, 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’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
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, according to Bryan.
[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.]
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January 7th, 2013
The better, up-to-date ballistics programs let you select either G1 or G7 Ballistic Coefficient (BC) values when calculating a trajectory. The ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. You’ve probably seen that G7 values are numerically lower than G1 values for the same bullet (typically). But that doesn’t mean you should select a G1 value simply because it is higher.
Some readers are not quite sure about the difference between G1 and G7 models. One forum member wrote us: “I went on the JBM Ballistics website to use the web-based Trajectory Calculator and when I got to the part that gives you a choice to choose between G1 and G7 BC, I was stumped. What determines how, or which one to use?”
The simple answer to that is the G1 value normally works better for shorter flat-based bullets, while the G7 value should work better for longer, boat-tailed bullets.
G1 vs. G7 Ballistic Coefficients — Which Is Right for You?
G1 and G7 refer both refer to aerodynamic drag models based on particular “standard projectile” shapes. The G1 shape looks like a flat-based bullet. The G7 shape is quite different, and better approximates the geometry of a modern long-range bullet. So, when choosing your drag model, G1 is preferrable for flat-based bullets, while G7 is ordinarily a “better fit” for longer, boat-tailed bullets.
Drag Models — G7 is better than G1 for Long-Range Bullets
Many ballistics programs still offer only the default G1 drag model. Bryan Litz, author of Applied Ballistics for Long Range Shooting, 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’s the results of my testing on two low-drag, long-range boat-tail bullets, so you can see how the G1 and G7 Ballistic coefficients compare:
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, according to Bryan.
[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.]
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May 28th, 2017
Berger Bullets’ much-awaited 200.20X bullet is now available at Midsouth Shooters Supply for $54.65 per 100*. That’s not inexpensive, but this new design could well prove to be the “bullet to beat” for F-TR competition with the .308 Win cartridge. With a high Ballistic Coefficient (0.640 G1, 0.328 G7), the new 200.20X Hybrid Target projectile (Part #30417) should have less wind drift than other .30-caliber bullets in its weight range. The new 200.20X is even more slippery than Berger’s own older 200gr Hybrid (Part #30427), which has a 0.316 G7 BC. The 200.20X bullet has a shorter bearing surface than Berger’s 200gr Hybrid, which should allow higher velocities, and (perhaps) enhanced barrel life. The shorter bearing surface also makes this bullet easy to load and shoot in standard chambers, which means you don’t need a special long-throated reamer to make it work.
The new 200.20X has a 0.328 G7 BC compared to 0.316 G7 for the older 200 grain .30 caliber Hybrid. That’s a significant, 4% reduction in drag. Recommended twist for the new bullet is 1:10″, same as with the earlier 200-grainer.
Tested and Endorsed by U.S. Rifle Team (F-TR)
Developed with extensive testing by U.S. Rifle Team members, Berger’s new 200.20X bullet is optimized for F-TR competition with the .308 Win cartridge. Compared to the standard 200 grain Hybrid Target, the 200.20X has a longer boat tail, longer nose, and a shorter bearing surface. The longer nose and tail of the 200.20X allow the bullet to fly with less drag and a higher BC, which means fewer points lost to wind. Like other Berger Hybrid designs, this bullet is more “forgiving” about seating depths that pure VLD designs. Shooters should find that the 200.20X works well at various OALs, both “jumped” and seated into the lands. Bryan Litz recommends starting with this bullet .020 or more off the lands. When the bullet is jumped a bit, the accuracy should hold pretty well even as the throat moves out.
After extensive field testing at 600-1000 yards, the U.S. Rifle Team (F-TR) has named the Berger 200.20X as the Team’s official bullet of choice. Shown above are Dan Pohlabel and Bill Litz (shooter).
*Grafs.com ($52.99/100) and PrecisionReloading.com ($53.99/100) will also sell this new bullet, but both these vendors are currently awaiting delivery. We’re told that supplies should arrive soon.
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November 2nd, 2016
Sierra’s new 110gr 6mm MatchKing is so new you won’t even find it on Sierra’s website. But MidwayUSA has it listed as “coming soon”. This new bullet, optimized for a 1:7″-twist barrel, promises class-leading ballistics. The listed G1 Ballistic Coefficient (BC) is an impressive 0.617 (sorry, no G7 BC has been stated). That’s 12.8% higher than the 0.547 G1 BC Sierra claims for its older 107gr MatchKing. That’s a very significant improvement. We attribute the reduced drag of the new 110-grainer to an improved hybrid-ogive bullet shape along with much smaller meplats. Sierra has not yet confirmed that it is pointing the meplats of the new 6mm 110s at the factory, but we expect that may be the case. In this respect the 110-grainers could be like Sierra’s excellent 183gr 7mm MatchKings, which come with tight, pointed tips right out of the box.
G1 vs. G7 and Listed BCs vs. Tested BCs — What You Need to Know
If you look at the table above you’ll see that Sierra’s claimed 0.617 G1 BC for the new 110gr MK is higher than the 0.536 Berger lists for its 105gr 6mm Hybrid and higher than the 0.536 Hornady lists for the new 108gr 6mm ELD Bullet. We do think Sierra’s 110-grainer will prove to have the highest BC of the bunch, based on recent comparison tests by Sierra.
Let’s explain… Sierra lists a 0.547 G1 BC for its 107-grain MatchKing. Sierra tells us that the the .547 listed BC is for the current lots of 107-grainers which are pointed by Sierra. Sierra’s Matt Reams states that the new 110-grainers definitely have less drag than the current Sierra 107gr MKs or Berger 105gr Hybrids: “We have shot the pointed 107s side by side (raced) in our 300-meter range next to the [Berger] 105s and our pointed 107s had a higher BC between those two lots. In the comparison we did, our lot of new pointed 107s had a slightly higher BC than the [Berger] 105s. The 110s are significantly higher than both.”
In the real world, Sierra’s new 110gr 6mm MatchKing may not have as big an edge over the competition as it seems from Sierra’s claimed 0.617 G1 BC. (The G7 numbers may be closer.) Nonetheless, we do expect that Sierra’s new 110-grainer will be very competitive, and may actually have best-in-class BC. And if the new 110gr SMKs come “tipped” from the factory that will be a very good thing.
Anybody currently shooting a heavy 6mm bullet in competition should look at the new 110gr MatchKing when it becomes available. It could prove to be a winner. NOTE However — Sierra recommends a true 1:7″-twist barrel to stabilize the new 110-grainers.
New Product Tip from Boyd Allen. We welcome reader submissions.
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August 29th, 2015
You’ve heard the rumors of a new ultra-high BC 7mm bullet from Berger. Well the rumors are true. Berger is now shipping test samples of its new 195-grain 7mm Elite Hunter Bullet, part # 28550. This bullet boasts jaw-droping 0.755 G1 and 0.387 G7 Ballistic Coefficients. Those are stunningly high numbers. Compare that to 0.674 G1 and 0.345 G7 BCs for the previous BC king amoung 7mm projectiles, Berger’s own 180 gr Match Hybrid Target.
We’re certain the “orange box” 195gr Elite Hunter will soon see use by F-Open competitors. This ultra-high BC projectile could be a “game-changer” in long-range shooting when used in cartridges such as the 7mm RSAUM, 7mm WSM and even bigger 7mm magnums. Recommended barrel twist rate is 1:8.3″, with a stated “minimum” twist of 1:9″.
We ran some numbers through the JBM Ballistics program*, comparing the new 195-grainer with Berger’s popular 180gr Hybrid. The results were eye-opening. The projected drop is significantly less. Most importantly, this new 195gr bullet moves a LOT less in the wind at 1000 yards. This should translate into higher scores for F-Class shooters — that wide ‘9’ shot may stay in the ’10’ ring. In fact, based on the JBM trajectory calculation, with a 10 mph 90° crosswind, the 195gr bullet will have over SEVEN INCHES less wind drift at 1000 yards than the 180-grainer (46.0″ vs. 53.1″). That’s a big deal, a very big deal…
| Comparative Ballistics 195gr vs. 180gr Berger 7mm Bullets (10 mph 90° Crosswind) |
| Berger 7mm 195gr Elite Hunter 2950 fps |
Berger 7mm 180gr Hybrid Target 2950 fps |
Drop at 800 yards: 135.5″
Windage at 800 yards: 28.0″ |
Drop at 800 yards: 140.9″
Windage at 800 yards: 32.2″ |
Drop at 1000 yards: 237.9″
Windage at 1000 yards: 46.0″ |
Drop at 1000 yards: 250.0″
Windage at 1000 yards: 53.1″ |
Drop at 1200 yards: 380.1″
Windage at 1200 yards: 69.6″ |
Drop at 1200 yards: 404.2″
Windage at 1200 yards: 81.2″ |
* Variables were set to 55.4° F, 1000′ elevation, standard Atmosphere at Altitude, 2950 fps muzzle velocity. You can use JBM Ballistics to compare at different MVs.
UPDATE from Berger
After we broke this story, Berger Bullets wanted to clarify some points. Berger explained:
“This bullet is in the testing phase and has not been officially launched. We sent this bullet out for some public testing to make sure that we had positive feedback before we moved forward with an official launch.
We want to see how it performs in multiple rifles and different chamberings.
This bullet was made for hunting purposes, we realize there are shooters who would like to take these out for target shooting, like F-Class. However, we are not certain how they will perform. If things are successful we would like to eventually launch a target version.”
The information on the label you have pictured on your article has been updated.
Twist Rates
Minimum: 1:9″
Optimum: 1:8.3″
Ballistic Coefficients
G7 BC: .387
G1 BC: .754
How to Get Berger’s 195gr Elite Hunter Bullets
These bullets are so new you won’t find them on the Berger Bullets website yet. As Berger explained above, these bullets are still in a final testing phase. Most of the early production runs have been sent out for testing purposes. If you have specific questions, you can send an email to Berger via this CONTACT PAGE. Otherwise you can phone Berger, Mon-Fri, at 714-441-7200. Please try the email option first.
The Extreme Store is listing the Berger 195gr 7mm Elite Hunter Bullet at $62.00 per 100 bullets, not including shipping.
Bullet boxes photo courtesy Ryan Pierce, PiercisionRifles.com
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March 22nd, 2024
Want to improve your understanding of Ballistics, Bullet Design, Bullet Pointing, and other shooting-related tech topics? Well here’s a treasure trove of gun expertise. Applied Ballistics offers dozens of FREE tech articles on its website. Curious about Coriolis? — You’ll find answers. Want to understand the difference between G1 and G7 BC? — There’s an article about that.
“Doc” Beech, technical support specialist at Applied Ballistics says these articles can help shooters working with ballistics programs: “One of the biggest issues I have seen is the misunderstanding… about a bullet’s ballistic coefficient (BC) and what it really means. Several papers on ballistic coefficient are available for shooters to review on the website.”
Credit Shooting Sports USA Editor John Parker for finding this great resource. John writes: “Our friends at Applied Ballistics have a real gold mine of articles on the science of accurate shooting on their website. This is a fantastic source for precision shooting information[.] Topics presented are wide-ranging — from ballistic coefficients to bullet analysis.”
Here are six (6) of our favorite Applied Ballistics articles, available for FREE to read online. There are dozens more, all available on the Applied Ballistics Education Webpage. After Clicking link, select Plus (+) Symbol for “White Papers”, then find the article(s) you want in the list. For each selection, then click “Download” in the right column. This will send a PDF version to your device.
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March 19th, 2024
As does Lapua and some other leading bullet-makers, Barnes now uses radar to determine bullet BC values and ballistic data for its match bullets and ammunition. Barnes employs advanced Doppler Radar to record bullet speeds at multiple distances out to 1500 yards.
The Doppler radar system gathers thousands of data points as a bullet flies downrange. This radar data is used to generate a bullet specific drag curve, and then fed into a modern 6 Degree of Freedom (DOF) [ballistics software program] to generate precise firing solutions.
Determining Bullet Ballistics with Doppler Radar Data
How do you build better (more precise) ammo drop tables? With radar, that’s how. Barnes Bullets is using Doppler Radar to develop the drop tables for its Precision Match line of factory ammunition. The Doppler radar allows Barnes to determine actual velocities at hundreds of points along a bullet’s flight path. This provides a more complete view of the ballistics “behavior” of the bullet, particularly at long range. Using Doppler radar, Barnes has learned that neither the G1 nor G7 BC models are perfect. Barnes essentially builds a custom drag curve for each bullet using Doppler radar findings.
Use of Doppler Radar to Generate Trajectory Solutions
by Barnes Bullets, LLC
Typical trajectory tables are generated by measuring only two values: muzzle velocity, and either time-of-flight to a downrange target, or a second downrange velocity. Depending on the test facility where this data is gathered, that downrange target or chronograph may only be 100 to 300 yards from the muzzle. These values are used to calculate the Ballistic Coefficient (BC value) of the bullet, and the BC value is then referenced to a standardized drag curve such as G1 or G7 to generate the trajectory table.
 This approach works reasonably well for the distances encountered in most hunting and target shooting conditions, but breaks down rapidly for long range work. It’s really an archaic approach based on artillery firings conducted in the late 1800s and computational techniques developed before the advent of modern computers.
There is a better approach which has been utilized by modern militaries around the world for many years to generate very precise firing solutions. Due to the sizeable investment required, it has been slow to make its way into the commercial market. This modern approach is to use a Doppler radar system to gather thousands of data points as a bullet flies downrange. This radar data is used to generate a bullet specific drag curve, and then fed into a modern 6 Degree of Freedom (DOF) [ballistics software program] to generate precise firing solutions and greatly increase first-round hit probability. (The 6 DOF software accounts for x, y, and z position along with the bullet’s pitch, yaw, and roll rates.)
Bullet-Specific Drag Curves Derived from Radar Data
Barnes’ advanced Doppler radar system can track bullets out to 1500 meters, recording the velocity and time of flight of that bullet every few feet along the flight path. The noteworthy graph below shows a Doppler Radar-derived, bullet-specific drag curve alongside the more common G1 and G7 curves:
Neither of the standard curves is a particularly good match to our test bullet. In the legacy approach to generating a downrange trajectory table, the BC value is in effect a multiplier or a fudge factor that’s used to shift the drag curve of the test bullet to try and approximate one of the standard curves. This leads to heated arguments as to which of the standardized drag curves is a better fit, or if multiple BC values should be used to better approximate the standard curve (e.g., use one BC value when the velocity is between Mach 1 and Mach 2, and a different BC value when the velocity is between Mach 2 and Mach 3.) Barnes’ approach to creating trajectory tables is to generate bullet-specific drag curves, and use that data directly in a modern, state-of-the-art, 6 DOF ballistics program called Prodas to generate the firing solution.
Story tip from EdLongrange. We welcome reader submissions.
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January 18th, 2024
 Need a simple, easy-to-use drop chart for your rifle? Something you can tape right to the buttstock? Then check out Hornady’s handy Online Ballistics Calculator. This user-friendly calculator will compute your drops accurately, and output a handy “Cheat Sheet” you can print and attach to your rifle.
Here’s how it works. From the Ballistics Calculator Page, first select 4DOF or Standard. Next input G1 or G7 BC values, muzzle velocity, bullet weight, zero range, and a few other variables.
Click “Calculate” to view the full chart (shown below). Then click “View Cheatsheet” and the simpler, 4-line Drop Chart (shown above) appears. Click “Print” and you’re done!
Choose Basic Table or Advanced Version with More Variables
The online ballistics caculator is easy to use. You can select the basic version, or an advanced version with more data fields for environmental variables (altitude, temperature, air pressure, and humidity). You can also get wind drift numbers by inputing wind speed and wind angle.
Conveniently, on the trajectory output, come-ups are listed in both MOA and Mils — so this will work with either MOA clicks or Mil-based clicks. There are more sophisticated ballistics solvers available on the web, such as the outstanding Applied Ballistics Online Calculator, but the Hornady Calculator is very simple and easy to use. If you just want a basic drop chart, you may want to check this out.
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December 9th, 2023
This is one of the very best books ever published about Long Range shooting. Based on sophisticated testing and research, this 356-page hardcover from Applied Ballistics offers important insights you won’t find anywhere else. Modern Advancements in Long Range Shooting – Volume II, a major treatise from Bryan Litz, is chock full of information, much of it derived through sophisticated field testing. As Chief Ballistician for Berger Bullets (and a trained rocket scientist), author Bryan Litz is uniquely qualified. Bryan is also an ace sling shooter and a past F-TR National Champion. Moreover, Bryan’s company, Applied Ballistics, has been a leader in the Extreme Long Range (ELR) discipline.
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AUDIO FILE: Bryan Litz Talks about Modern Advancements in Long Range Shooting, Volume 2. (Sound file loads when you click button). |
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Volume II of Modern Advancements in Long Range Shooting ($44.95) contains all-new content derived from research by Applied Ballistics. Author Bryan Litz along with contributing authors Nick Vitalbo and Cal Zant use the scientific method and careful testing to answer important questions faced by long range shooters. In particular, this volume explores the subject of bullet dispersion including group convergence. Advanced hand-loading subjects are covered such as: bullet pointing and trimming, powder measurement, flash hole deburring, neck tension, and fill ratio.
Each topic is explored with extensive live fire testing, and the resulting information helps to guide hand loaders in a deliberate path to success. The current bullet library of measured G1 and G7 ballistic coefficients is included as an appendix. This library currently has data on 533 bullets in common use by long range shooters. |
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Bryan tells us that one purpose of this book is to dispel myths and correct commonly-held misconceptions: “Modern Advancements in Long Range Shooting aims to end the misinformation which is so prevalent in long range shooting. By applying the scientific method and taking a Myth Buster approach, the state of the art is advanced….”
Bullet Dispersion and Group Convergence
Part 1 of this Volume is focused on the details of rifle bullet dispersion. Chapter 1 builds a discussion of dispersion and precision that every shooter will benefit from in terms of understanding how it impacts their particular shooting application. How many shots should you shoot in a group? What kind of 5-shot 100 yard groups correlate to average or winning precision levels in 1000 yard F-Class shooting?
Chapter 2 presents a very detailed investigation of the mysterious concept of group convergence, which is the common idea that some guns can shoot smaller (MOA) groups at longer ranges. This concept is thoroughly tested with extensive live fire, and the results answer a very important question that has baffled shooters for many generations.
 Part 2 of this Volume is focused on various aspects of advanced hand-loading. Modern Advancements (Vol. II) employs live fire testing to answer the important questions that precision hand loaders are asking. What are the best ways to achieve MVs with low ES and SD? Do flash hole deburring, neck tension, primer selection, and fill ratio and powder scales sensitivity make a difference and how much? All of these questions are explored in detail with a clear explanation of test results.
One of the important chapters of Part 2 examines bullet pointing and trimming. Applied Ballistics tested 39 different bullet types from .224 through .338 caliber. Ten samples of each bullet were tested for BC in each of the following configurations: original out of the box, pointed, trimmed, pointed and trimmed. The effect on the average BC as well as the uniformity in BC was measured and tabulated, revealing what works best.
Part 3 covers a variety of general research topics. Contributing author Nick Vitalbo, a laser technology expert, tested 22 different laser rangefinders. Nick’s material on rangefinder performance is a landmark piece of work. Nick shows how shooters can determine the performance of a rangefinder under various lighting conditions, target sizes, and reflectivities.
Chapter 9 is a thorough analysis of rimfire ammunition. Ballistic Performance of Rifle Bullets, 2nd Edition presented live fire data on 95 different types of .22 rimfire ammunition, each tested in five different barrels having various lengths and twist rates. Where that book just presented the data, Chapter 9 of this book offers detailed analysis of all the test results and shows what properties of rimfire ammunition are favorable, and how the BCs, muzzle velocities and consistency of the ammo are affected by the different barrels.
Chapter 10 is a discussion of aerodynamic drag as it relates to ballistic trajectory modeling. You will learn from the ground up: what an aerodynamic drag model is, how it’s measure and used to predict trajectories. Analysis is presented which shows how the best trajectory models compare to actual measured drop in the real world.
Finally, contributing author Cal Zant of the Precision Rifle Blog presents a study of modern carbon fiber-wrapped barrels in Chapter 11. The science and technology of these modern rifle barrels is discussed, and then everything from point of impact shift to group sizes are compared for several samples of each type of barrel including standard steel barrels.
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