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June 13th, 2017
Cartridge Choices for F-Class Competition
By Emil Kovan
Kovan Match Rifles LLC, www.matchrifles.com
There are hundreds of cartridge types capable of winning in F-Open. For F-TR you can shoot either the .223 Rem or .308 Win, but you have many load options. This article will focus on proven choices, currently used by the top F-Class shooters in the world. Our discussion will analyze cartridge selection based on the four different F-Class sub-disciplines: Open Mid-Range, Open Long-Range, F-TR Mid-Range, and F-TR Long Range.
Click image to view full-screen photo.
Mid-Range F-Open Cartridges
For starters, a .300 WSM is certainly capable of winning mid-range matches but it is not ideal. So what is ideal, and why? F-Class Mid-Range matches usually are usually shot at 300, 500, or 600 yards — or all three. At those distances the 6mm and 6.5mm cartridges rule. In moderate conditions, the 6mm Dasher is unbeatable. Its low recoil along with its super grouping ability and good ballistics make it my number one choice for Mid-Range.
Best bullets for the 6mm Dasher are: Vapor Trail 103gr, Berger 105 Hybrid, 108 BT, and 105 VLD (hunting). Best powders are: Varget, H4895, and Reloder 15.
Choices for Mid-Range in Tougher Conditions:
We all know that conditions are not always “moderate” that’s why something a little bit bigger will save you a “Nine” or two. The 6.5X47 Lapua was designed for 300-meter competition, but as soon as it was released, it was adopted by F-Class, benchrest, and tactical shooters. It offers great ballistics with very low recoil and big “accuracy window”. Lapua makes great brass for it (no surprise there) and Berger makes great bullets: 130gr VLD, 140gr VLD, 140gr Hybrids. Best powders in most barrels are Varget and H4350, I don’t use double-based powders such as Reloder 17 and the Vihtavuori N500 series because of their unpredictable performance day to day (greater temp sensitivity).
The 6.5X47 Lapua necked down to 6mm is also a great option for mid range matches. I was able to easily get 3200 fps with 105 hybrids and H4350.
Choice for Long-Range F-Open Competition
In Long-Range F-Open Class (out to 1000 yards), the big, high-BC bullets rule. If I had to pick one cartridge for F-Class (both mid- and long-range) I would pick the .284 Winchester or one of its variants. The .284 Win is currently dominating in F-Open competition. It offers great barrel life, it is super-easy to tune and its recoil is very manageable. The best bullets for it by far (in my opinion), are the Berger 180 Hybrids. But Sierra’s new 183gr MK bullet (with factory-uniformed meplats) seems to perform very well as does the Berger 180 VLD. Best powders for the .284 Win are H4350 and H4831SC.
Long-Range Only F-Open Cartridge
As much as I like the .284 Win, for long-range competitions I like the .300 WSM even more. If you look at a .300 WSM and a 6mm Dasher side by side, they appear almost identical in geometry — the .300 WSM looks like an “super-sized” Dasher. Both cartridges are currently the “darlings” of long-range benchrest due to their extraordinary grouping ability and huge “node’’ windows. Big accuracy windows allow loads to perform well in different conditions and geographical locations. That’s obviously very important if you travel to compete. The .300 WSM loaded with Berger 215gr or 230gr Hybrids is very tough to beat at long range, and it is currently my number one choice.
The 7mm RSAUM is another outstanding long-range round. It resembles a 6BR on steroids and it is almost as easy to tune. Best bullets for it are Berger 180gr Hybrids, 195gr EOLs, and Sierra’s 183gr MatchKing. Best powders for the 7mm RSAUM are: H4350, H4831SC, and VV N160.
Top Caliber/Bullet Combos for F-TR
In F-TR competition, the choice is clear — a .308 Win throated for Berger 185gr BTLRs and 200gr Hybrids will win in mid-range AND long-range comps. Many championships have been won, and many records set with those two bullets in the .308 Win. To quote Danny Biggs (a two times FTR National Champion) “The 185 BTLR is the best bullet for .308 Win ever made”.
The Berger 215gr Hybrids have been used to win many competitions including recently the 2015 F-Class Nationals. Bryan Litz won both the Mid-Range and Long-Range 2015 Championships using 215s. Bryan’s rifle is shown below:
I recommend chambers throated for the 185/200 grain projectiles over the 215/230 grain bullets. The reason is that if you have your barrel throated out for the 215s or the 230s, you could have a “slow” barrel and max out on pressure before the desired velocity is reached. Optimum freebore for the 230s is too long for the 185/200s, so you would be limited to using only 215/230gr bullets in that barrel.Furthermore, the recoil increase with heavier bullets is substantial, causing the rifle to be more difficult to shoot.
 .223 Rem — Not A Competitive Option
I would stay away from the .223 Remington. On paper the 90gr VLD will shoot inside most .308 Win loads even at a 1000 yards. But in reality, on average, the .223 Rem, regardless of what powder/bullet combo is used, cannot compete with the .308 Win. [Editor: The equipment lists at major F-TR matches will confirm Kovan’s conclusion here.]
Conclusion (and Other Options)
This article covers only the (currently) most popular cartridge/bullet combos for F-Class (F-Open and F-TR). As I said in the beginning, many cartridge types are capable of winning but are not listed due to their low popularity, case design, or lack of quality components. All of the above information is based on my personal experience and it is meant to help new shooters choose the right cartridges for F-Class matches. Thanks for reading and good luck — Emil Kovan
 Emil Kovan Competition History:
– 2014 F-Class Open National Champion
– 2015 F-Class Open National Championship, Silver Medal
– F-Class Open National Championship Teams, 2015, 2014, 2013, Shooting Team Member
– Over 15 wins in Regional and State Championships in Palma, F-TR, F-Open
– 2013 U.S. National Team Member
– 2017 U.S. National Development Team Member
June 8th, 2017
We created this custom target in 5 minutes using PrintTargets.net. If you like it, DOWNLOAD HERE.
AccurateShooter.com has a HUGE collection of FREE downloadable PDF targets. We offer a very wide range of target designs: Load Development Grids, NRA Bullseye targets, Official-Size BR targets, Realistic Varmint Targets, Silhouette Shapes, Fun Plinking Targets, and even specialized tactical training targets. If our collection of free targets isn’t enough, or if you want to create a new kind of target — you’re in luck. There’s an Australian-based interactive website, PrintTargets.net, that allows you to create your own customized, printable PDF targets. Shown below are just a few of the target designs you can create in minutes:
Just follow the step-by-step instructions to set paper size, layout, bullseye color, line thickness, number of rings and diameter. You can even add Score Numbers to your target rings. PrintTargets.net is easy and fun to use. It’s much faster to create targets this way than to try to draw a series of circles with PowerPoint or MS Paint.
CLICK HERE to Design Your Own Downloadable Targets
Power-User Tip: PrintTargets.net even offers a handy diamond-grid calibration diagram that you can add to your custom target designs. You’ll find the calibration grid as option #15 when you design your target — just scroll all the way down the PrintTargets.com home page.
CLICK Graphic to Create Your Own Targets.
May 25th, 2017
If you’re one of those folks who doesn’t wear eye protection, you need to check out the LuckyGunner Labs Eye Protection Test. For those who DO wear safety glasses — don’t assume that everything is OK. Just because you purchased name-brand “safety glasses” doesn’t mean that you are getting truly effective protection. In fact, many forms of protective eyewear sold today are flimsy, or poorly made. Consequently, they won’t stop even low-energy, slow-velocity fragments.
CLICK HERE to Read Complete Eyewear Test Report by LuckyGunner Labs.
 Two years ago, LuckyGunner Labs conducted very extensive field tests of 28 types of eyewear, ranging in price from $7 to $220. Remarkably, some of the most expensive safety eyewear performed no better than $10 items. Many of the products failed shockingly — with the lenses coming right out of the frames when hit with pellets. LuckyGunner recorded these kind of failures even with ANSI Z87-“approved” eyewear. The reason is that the Z87 test is not tough enough: “The basic ANSI standard is referred to as Z87, and you’ll see this marked in a number of locations on most eye protection marketed to shooters. However, the Z87 impact standard involves a .25″ steel ball traveling at 150 fps — this is fine for protecting eyes from debris that might fall or be thrown, but is not extremely relevant to shooters, who are dealing with objects traveling at much higher velocities.”
| Standard |
Impact speed |
Caliber/Size |
ANSI Z87.1-2003
High Velocity |
150 feet/second
45 meters/second |
0.25″ diameter steel ball
(25 caliber) |
Mil-PRF-31013
Vo ballistic test |
640-660 feet/second
195 meters/second |
0.15 inch diameter steel projectile (15 caliber) |
The testers recommend you select eyewear that meets military specification (above and beyond ANSI Z87). The MIL-PRF-31013 Standard covers projectiles up to 650 feet per second. This is much more stringent. Additionally, you want to replace often-used protective eyewear every year or so. Long-term exposure to UV radiation can weaken polycarbonate and lessen its ability to withstand impacts.
SUMMARY — What to Look for in Protective Eyewear
THE GOOD — Eyewear Protects Against Direct Hit with .22 Short Bullet
APEL Revision Sawfly eyewear was shot with a .22 Short, pushing a 29 grain bullet at 710 fps. That’s not powerful by modern firearm standards, but this might be fairly representative of a ricochet bullet fragment. The Sawfly lens stopped this 29gr bullet with minimal damage to the cheek area.
THE BAD — Remington Eyewear Lenses Separate. Right Lens Enters Eye Socket
The most gruesome example was the cheap Remington eyewear which shed both lenses back towards the eyes, one of which embedded itself into the eye socket. The real-world implications of this action are disturbing to say the least.
THE UGLY — Prescription Glasses Failed Miserably
Many ranges don’t see any need for protective eyewear beyond prescription glasses. However, most prescription lenses offer little if any protection. If the prescription lenses are glass, this can create more problems. As shown below, these prescription glasses offered no ballistic protection, and, in fact, proved more dangerous to the eyes due to the flying glass shards.
Results Chart, Video Clips, and Photos copyright Luckygunner.com.
Summary and Conclusions:
For faster-moving projectiles such as ricochet fragments, you need high quality, tested eye protection. LuckyGunner recommends eyewear with a single (one-piece) lens for any activity where your face might be struck by small, fast-moving objects. Individual lenses detach from the frames once a certain level of force is reached, and they are driven back into the eye sockets, where considerable damage may be done. There are good examples of protective eyewear with two separate lenses, but a broad, one-piece lens distributes force much better.
 A wide, comfortable, and preferably soft rubber nosepiece is critical. Along with good “arms”, this will serve to keep the eye protection in place and will also reduce the chances of the lens being driven down or back into the face with enough force to damage the orbital bones.
A frame that connects across the top of the lens, not individual arms which attach to the outside corners of the lens, is recommended. This will reduce the chances of the lens detaching from the frame under impact (it’s still possible, just less likely). Some types of eye protection actually use the frame to absorb impact and distribute force.
NOTE: Andrew, the author of the LuckyGunner Eyewear report, was a former Navy Corpsman. Accordingly, he is familiar with health and safety matters.
May 22nd, 2017
On the Shooting Sports USA website, there’s a great profile of Kevin Nevius, one of America’s leading competitive marksmen. Kevin is best known for his smallbore success but he has also an impressive record in long-range centerfire competition — In 2005 and 2006 he won the Sierra Trophy at Camp Perry in 1000-yard competition. This was followed by smallbore National Championships in 2008, 2010, and 2014. This story, penned by gunwriter Hap Rocketto, covers Kevin’s career, which has included multiple championships and many records.
“My brother got me into long range varmint hunting and I started building my own guns very early,” Nevius told Dan Holmes in a Pronematch.com interview. “I had a hunting friend who shot indoor smallbore who started me in three position and I was hooked.”
Here are highlights from Hap Rocketto’s Profile of Kevin Nevius:
 Champion shooter Kevin Nevius grew up in a household that did not allow firearms, an unlikely beginning for one of the United States’ premier prone rifleman and gunsmiths. Once out on his own he fell in with his brother who enjoyed long-range varmint hunting. His natural bent for things mechanical (he is a professional structural engineer) soon had him tinkering with rifles, which eventually led him to building his own.
Everything fell into line for him in smallbore during the 2008 season. After shooting a series of training matches in which he was most successful, he arrived at Camp Perry at the peak of performance and won his first National Smallbore Rifle Conventional Prone Championship. Kevin came back strong in 2010, winning the inaugural individual National Smallbore Rifle Metric Prone Championship, as well as the team title at Bristol, IN. [Kevin then won the Smallbore Conventional Prone Championship in 2014 with a practically perfect score of 4799-390X (LINK).]
Along the way, Nevius has won some impressive national records. In conventional competition he co-holds the 1200-shot metallic sight aggregate record of 1200-102X. He was just one shot short of perfection in the 480 aggregate, where he holds the civilian record of 4799-412X, just one point behind, and 11 Xs ahead of, Joe Hein’s 4800-401X open record.
Kevin Nevius hopes to build a smallbore rig capable of 3/8-MOA at 100 yards.
Building the Ultimate Rimfire Prone Rifle
Kevin is not just a great trigger-puller. He also smiths his own rifles. His current goal as a gunsmith is to build a rimfire rifle that will shoot 3/8″ groups at 100 yards. That’s a big challenge — 3/8-MOA represents very good accuracy for a centerfire rifle with handloaded ammo. But if any rimfire smith can build a rifle that will shoot that well at 100, it’s probably Kevin.
May 7th, 2017
Click to zoom image
We first ran this story a couple years back. We’re republishing it today as a reminder to our readers that safety should be their paramount concern at the range. Avoid distractions and always check your barrel for obstructions before you chamber a round or pull the trigger. A moment of inattention can result in a catastrophic kaboom …
Discharging a .338 Lapua Magnum round with a cleaning rod in the barrel — that’s a recipe for disaster. What happens when a fired .338 caliber bullet and a cleaning rod try to occupy the same place at the same time? Well you get a catastrophic kaboom, with metal pieces flying all over the place, and a shooter very lucky to escape without serious injury. This incident occurred recently in Manatee, Florida, as reported by Sniper’s Hide member Queequeg. We thank SnipersHide.com for granting permission to publish these revealing images in the Daily Bulletin. CLICK HERE for more Kaboom info on the ‘Hide.
This story should serve as a chilling reminder to follow proper safety practices whenever you are at the range. Always check to make sure there is no obstruction in the bore BEFORE loading a live round.
.338 Lapua Magnum + Cleaning Rod + Inattention = Kaboom!
Kaboom at Manatee!
Sniper’s Hide member Queequeg recently published shocking photos of a catastrophic kaboom involving a .338 Lapua Magnum (Savage action). The action was blown off the rifle, shrapnel went through the roof, and the barrel split at the tenon before taking an excursion downrange. The action did crack in the front but the lugs remained engaged so the bolt did not slam to the rear (luckily for the shooter).
Here’s the report: “This happened [January 20, 2014] at the Manatee Gun and Archery Club. Al, Ren and myself were there with a couple other folks. Ren was at bench 12, I was at 13. The fellow at 11 was running a Savage .338 Lapua. He had a very bad day! He damn sure could have killed himself and quite likely Ren as well.”
Queeqeg added: “After the boom, I heard Ren ask ‘Are you alright’ and then turned to look in time to see the fellow reacting in total shock — literally stunned. Ren and I went over to him and could not see any major injuries. Ren was uninjured as well but had a lot of fiberglass splinters on him. The barrel nut is what I presume punched the two holes in the roof. The shooter is a regular there[.] He had been having a problem with sticky cases though he said he was certain the loads were mild. That’s why he was content to knock the sticky ones out with the rod. He simply forgot to remove the rod after knocking out the last stuck case. You can see what happened next.”
To learn more about this incident, go to the original Snipers Hide Forum Thread. There you’ll find more details and over four pages of related discussions.
The Important Lesson Here
What did the .338 LM shooter do wrong here? You will say — “Well that’s obvious, he left a cleaning rod in the barrel and then shot a round.” Yes, that was a potentially fatal error. But that was his second mistake — one that occurred only because he made a more fundamental judgment error first.
The FIRST mistake was not acknowledging the problem with his ammo. Had he heeded the warning signs, he would still have a rifle (and an unsoiled pair of trousers). When he first observed that he was having problems with extracting cases, a warning light should have gone off in his head. Presuming his extractor was not broken (and that the chamber was cut properly) he should have been able to extract his brass if he was running safe loads. The lesson here we all need to learn is that if you observe a serious ammo-related issue, it is time to stop shooting. Don’t try to invent work-arounds just to extend your range session, when there are clear signs that something is wrong, very wrong.
May 2nd, 2017
There’s a great interview with Bryan Litz of Applied Ballistics on Mia Rhode’s Life Of A Shooter’s Wife Blog. We recommend you read the full interview. Bryan offers many important insights that can benefit any precision shooter. It’s fascinating to learn about Bryan’s background and how he progressed in competitive shooting, starting with very basic equipment. As a “broke high school kid”, he got started on the cheap, paying for gear with wages from McDonald’s. Now he’s a globally-recognized expert in Ballistics and Long Range precision. You’ll enjoy reading the Full Interview. Here are some highlights…
 LOASW: When did you first become interested in shooting?
Bryan: My first memories of shooting were at the age of about 9 or 10. Pellet rifle in the back yard. My Dad taught me to shoot, stressing the importance of accuracy. I was driven to hit targets, mostly small targets at long distance. My grandfather was on the All-Army shooting team back in the ‘50s, and was distinguished in both rifle and pistol. Shooting is part of my family’s DNA and I benefited from that from a young age.
LOASW: What sparked your interest in Competitive Shooting and how old were you when you started competing?
Bryan: Hunting groundhogs in the farm-fields of Pennsylvania through high school is where I truly connected with long-range shooting. My Dad heard of a competition range (The Original Pennsylvania 1000 Yard Benchrest Club in Williamsport, PA). So we visited there one summer and I immediately found my trusty 22-250 inadequate for the job of 1000-yard benchrest shooting. So I saved my McDonald’s wages until I could afford a 7mm Remington Magnum and began competing in my first matches at the age of 15.
Learning with Limited Resources…
… It was a huge mis-match to my situation because benchrest is a highly gear-driven sport, and the winners typically have many $1000s of dollars wrapped up in equipment. I was a broke high school kid who needed my parents to drive me to the range my first year, and my second year, I had to rely on fellow competitors to jump start my old pick-up truck that was always breaking down. Nevertheless I enjoyed the hell out of shooting 1000 yards. I can honestly say that I don’t have any more FUN shooting these days with all the best equipment as compared to those bad ‘ol days when I had maybe $900 total wrapped up in all my gear. Those who remember me from those early days might recall the home-made shooting rest and McDonalds French fry box that I carried all my gear in. Later when I picked up prone/sling shooting, my shooting mat was a piece of carpet (pink, no less), and my shooting coat was a military field jacket with belts sewn in it.
Money was probably my biggest challenge when I started out. I had plenty of fun with my budget kit, but was certainly constrained by lack of access to quality gear. I overcame this with hard work and making the most of what I had. Learning how to mitigate the deficiencies of my equipment was an important stepping stone which has been highly valuable even now when I’ve got better stuff. It’s a good skill to have, to be able to spot something about to come unraveled.
LOASW: What advice would you give to someone new to competitive shooting?
Bryan: Find a mentor, someone who lives near you who has experience and is willing to share it. You will cut years off your learning curve if you can get someone to share their experience with you who’s “been there done that”.
April 26th, 2017
Click Photo to read full test results in Target Shooter Magazine.
Mother of All LR Primer Tests
If you shoot a .308 Win, or any cartridge that uses a Large Rifle (LR) primer, you should read an important article by Laurie Holland in Target Shooter Magazine. Holland, a talented shooter from the UK, tested no less than sixteen (16) different large primer types using a custom F-TR target rifle shot from the bench. Laurie loaded .308 Win ammo* with 16 LR primer varieties and then tested for average velocity, ES/SD, and group size. This may be the most comprehensive and thorough LR primer test ever done. Here are the primer types tested:
1. CBC Magtech 9½
2. CCI 200 LR
3. CCI BR2 Match
4. CCI 250 Magnum
5. Federal 210
6. Federal 210M Match
7. Federal 215M Magnum Match
8. Fiocchi Large Rifle |
9. Kynoch Large Rifle
10. Murom KVB-7 (PMC LR)
11. Norma Superflash LR
12. PMC LR Magnum
13. Remington 9½ LR
14. Remington 9½ M Magnum
15. Sellier & Bellot LR
16. Winchester WLR |
Test Rig: Osprey Rifles-built F-TR rifle with Savage PTA action, 32″ Bartlein 1:12″-twist ‘Heavy Palma’ barrel, and Dolphin Gun Company modular stock with an F-Open/Benchrest fore-end.
Some of Laurie’s results may surprise you. For example, would you guess that Sellier & Bellot primers had the lowest ES, by a significant margin? And get this, among ALL the primers tested, Rem 9½M Magnum primers produced the lowest velocity, while Rem 9½ LR (non-magnum) primers yielded the highest velocity. (The total velocity spread for all primers was 35 fps). That’s counter-intuitive and it’s odd that Rems were at opposite ends of the speed spectrum among ALL primers tested.
“The rationale for doing side-by-side tests is to see what effect primer choice has on ballistics, i.e. average velocities and MV consistency. There are a great many views on the subject, a few based on tests (including primer flame photography) but most apparently hearsay.” — Laurie Holland
Every serious hand-loader should definitely read the full test results to understand Laurie’s methodology and get all the details. This is an important test, with significant findings. But if you can’t spare the time right now, here are some highlights below:
Primer with Lowest Velocity: Remington 9½ M Magnum (2780 fps)
Primer with Highest Velocity: Remington 9½ LR (2815 fps)
Primer with Lowest ES/SD: Sellier & Bellot LR (12/3.1 fps)
Primer with Highest ES/SD: Remington 9½ M Magnum (47/14.0 fps)
Primer with Smallest Group Size: Remington 9½ LR (0.43″ average, three 5-shot groups)
Primer with Biggest Group Size: CBC Magtech 9½ (0.7″ average, three 5-shot groups)
Editor’s Comment: Laurie shot three, 5-shot groups at 100 yards with each primer type. The average group size for the top six primers varied by only 0.10″ (0.43″ to 0.53″), so one can’t conclude that one type is much better than another. Total group size variance (from best to worst) was 0.27″.
“The biggest surprise to me … came from an elderly (at least 10 years) lot of Czech Sellier & Bellot standard caps with an ES of 12 and SD of 3.1 fps, way below those of the nearest competitor. By contrast to the Fiocchis, they were an almost slack fit in the cases and this may have contributed to their consistent performance.” — Laurie Holland
NOTE: Values in chart are based on 15-Shot strings. The ES/SD numbers will therefore be higher than is typical with five-shot strings.
All ES/SD Values from 15-Shot Strings
Testing 16 primer types was a huge task — we commend Laurie for his hard work and thoroughness. This extensive test is an important contribution to the “knowledge base” of precision shooting. Laurie’s findings will doubtless influence many hand-loaders who hope to produce more consistent ammunition, or achieve better accuracy. Credit should also be given to Target Shooter Magazine for publishing the results. Well done gentlemen…
*Reloading method for Test Ammo: “Test batches consisted of 16 or 17 rounds for each primer, charges thrown by an RCBS ChargeMaster and checked on lab-quality electronic scales, adjusted if necessary to within ± 0.04gn, so any charge weight variation would be under 0.1 grain which equates here to 5 fps.”
April 20th, 2017
You may not realize it… but to get the optimum BC from your bullets (i.e. the lowest aerodynamic drag), you must spin the bullets fast enough. Bullet drag increases (as expressed by lower BC) if the bullet spins too slowly. Bryan Litz of Applied Ballistics explains how BC changes with twist rates…
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.
April 19th, 2017
This photo is one of Nightforce’s series of picturesque “Gunscapes”. SEE MORE HERE.
This story is not (directly) about firearms, or reloading gear, or any of the little details of our sport. It, instead, is about life… and, sadly, about death. The recent passing of a friend (and fellow shooter) got me to thinking, “I’m sixty — what if I only had ten more years to live — how would I want to live my life? What really counts the most? What things would I do differently? What dreams would I pursue?”
From the demographics of this website, I know we have thousands of readers in their 50s, 60s, and 70s. Hopefully we will all live long, happy, and fruitful lives. But it’s not a bad idea to consider that we are all mortal, and the clock is ticking. Consider this — in the United States, the average male life expectancy is 77 years*. Using that number as a benchmark, I personally may have just 15 more years to enjoy life and to do the things I love — shooting, traveling, sailing, camping, listening to music, being with friends and family. Breaking that down into months, I have 180 more months to do fun and rewarding stuff. Just 180 months — that’s a real number my brain can comprehend all too well. If I live an average lifespan, that means I also only have 780 more weekends to do all that I want to do. With less than 800 weekends remaining, I don’t want to waste a single one.
Living a Life with More Good Times, and Fewer Regrets
Recently, a group of men, very near the end of their lives, were surveyed. They were asked if they would do things differently if they could live their lives over again. The vast majority of these men gave surprisingly similar responses, which fit into five “Life Lessons”. These “Top 5 Regrets of the Dying” were reported in a story by Bronnie Ware, writing for the AARP online magazine. Ware writes: “When questioned about any regrets they had or anything they would do differently, common themes surfaced.” Here are the five regrets most often mentioned by older men:
1. I wish I’d had the courage to live a life true to myself, not the life others expected of me.
“This was the most common regret of all. When people realize that their life is almost over and look back clearly on it, it is easy to see how many dreams have gone unfulfilled. ”
Lesson: Don’t wait to follow your dreams. Be true to yourself.
2. I wish I didn’t work so hard.
“This came from every male patient [surveyed]. All of the men… deeply regretted spending so much of their lives on the treadmill of a work existence.”
Lesson: Don’t let your work crowd out other important aspects of life.
3. I wish I’d had the courage to express my feelings.
“Many people suppressed their feelings in order to keep peace with others. As a result, they settled for a mediocre existence and never became who they were truly capable of becoming.”
Lesson: Express yourself truthfully. Don’t suppress your feelings for decades.
4. I wish I had stayed in touch with my friends.
“There were many deep regrets about not giving friendships the time and effort they deserved. Many [were] so caught up in their own lives that they had let golden friendships slip by over the years.”
Lesson: Take an interest your friends’ lives; keep bonds of friendship strong.
5. I wish that I had let myself be happier.
“This is a surprisingly common [regret]. Many did not realize until the end that happiness is a choice.”
Lesson: Affirmatively pursue the things that bring you happiness. Don’t just stick to old habits.
Turn Off the Computer, and Do Something Memorable with Your Friends Today
How does this all apply to our shooting hobby? Well, if (like me) you are middle-aged (or older), go have some fun this weekend! Load up your rifle and get to the range. Don’t put off doing the things that make you happy. Call those old buddies you may not have seen in a long time. Renew friendships. Get out into nature. And start figuring out how you can live your dreams. As the saying goes, “Time waits for no man”.
*One of our readers pointed out that the numbers actually work out better than this, because once a man survives to later life, men of his surviving age cohort enjoy a projected lifespan longer than the average projected lifespan from birth. For example, using actuarial tables, a man born exactly 60 years ago (still alive today), has a calculated life expectancy of 23.4 years… meaning he would live to age 83.4 years, on average. CLICK HERE to see actuarial-predicted longevity based on your birthdate.
Practicing What I Preach…
As you read this, your Editor will NOT be sitting in front of a computer. Instead he will be on a boat, taking him 30 miles offshore to this beautiful spot. Three days with no internet, no TV, no Schedule Cs, and no traffic. Just good friends and unspoiled nature. Living like a kid again.
April 16th, 2017
 A.P. Lane’s Gold Medal-Winning Colt Revolver
This Colt Officer’s Model revolver, factory-fitted with a skeletonized hammer, belonged to legendary Olympic shooter A. P. Lane, who was known as the “Pistol Wizard”. Lane used this Colt Revolver to win FIVE Olympic Gold Medals — three in 1912 and two in 1920.
A.P. Lane was one of the greatest pistol shooters of his generation. He shot scores that were typically 25-50 points higher than those of his competitors. And he exhibited true Corinthian spirit. At the 1912 Olympics, Lane shared his match ammunition with another competitor who used that ammo to capture the Silver Medal (Lane won the Gold).
This revolver, factory-fitted with a skeletonized hammer, was used by American A.P. Lane in winning five Olympic Gold Medals in the 1912 and 1920 Olympic Games. It’s a .38 caliber, Officer’s Model centerfire revolver from the early 20th century. Olympian A.P. Lane’s Gun can be found in Gallery 13, Firearm Traditions for Today, at the NRA National Firearms Museum in Fairfax, Virginia. The Museum exhibit includes a panoply of Lane pieces – his revolver, his five Gold Medals, and the five Olympic certificates that went along with them.
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Watch Video History of the A.P. Lane Revolver
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