April 25th, 2015

16-Year-Old Girl Dominates National Junior Olympics

elizabeth marsh, arkansas, air rifle smallbore njosc

Elizabeth Marsh — remember the name. This girl’s got game, as the 16-year-old Arkansas native proved at the 2015 National Junior Olympic Championships (NJOSC). In a superb performance, young Elizbeth won BOTH the Air Rifle and Smallbore Events in the Ladies’ Division at NJOSC. Remarkably, her finals score beat the current Junior World Record.

Elizabeth first claimed top honors in Air Rifle, then she won the Smallbore event with a dominating performance. She shot a world-class Smallbore Final, besting her nearest opponent by 12.1 points. In fact, her Finals score of 459.3 is 3.5 points better than the current Junior World Record (455.8) set by China’s Ruijiao Pei at last year’s World Championship.

Her latest mentor, three-time Olympic medalist Matt Emmons, explained why Elizabeth has achieved so much success at a very young age:

“She has a ton of things going for her. First, she likes to shoot and wants to go far with it. Her approach is great. She has an excellent outlook of wanting to do very well, but not to the point of wanting it too much that she gets in her own way. She’s a good sportswoman… happy to shake someone else’s hand when they do well. On top of that, she’s not afraid to work. She trains hard and she trains smart. All of the above things set her apart from the average shooter her age. It’s almost like the perfect storm. As far as the future, that’s totally up to her.”

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April 22nd, 2015

Field Skills: Reading the Wind When Hunting

On LongRangeHunting.com, you’ll find a good article by Shawn Carlock about wind reading. Shawn is a veteran law enforcement marksman and a past USPSA national precision rifle champion. Shawn offers good advice on how to estimate wind speeds and directions using a multitude of available indicators — not just your wind gauge: “Use anything at your disposal to accurately estimate the wind’s velocity. I keep and use a Kestrel for reading conditions….The Kestrel is very accurate but will only tell you what the conditions are where you are standing. I practice by looking at grass, brush, trees, dust, wind flags, mirage, rain, fog and anything else that will give me info on velocity and then estimate the speed.”

Shawn also explains how terrain features can cause vertical wind effects. A hunter on a hilltop must account for bullet rise if there is a headwind blowing up the slope. Many shooters consider wind in only one plane — the horizontal. In fact wind has vertical components, both up and down. If you have piloted a small aircraft you know how important vertical wind vectors can be. Match shooters will also experience vertical rise when there is a strong tailwind blowing over an up-sloping berm ahead of the target emplacements. Overall, Shawn concludes: “The more time you spend studying the wind and its effect over varying terrain the more successful you will be as a long-range shooter and hunter.”

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April 6th, 2015

FREE Fun Targets from NSSF — Download and Print

Here are four FREE fun targets from the NSSF. These can be downloaded as PDF files for easy, scalable printing. Choose from four fun targets: Orange Clays, Fish in a Barrel, Cans on Fence, or Bacon Xs. To download any of the targets, right click and “Save Link As”. You can also click on the four large targets and they should open up in most browsers if you have the PDF reader installed. Have Fun!

Orange Clays

Fish in a Barrel

Cans on Fence

Bacon Xs

Download FREE Bullseye Targets
The NSSF also offers conventional bullseye-style targets on the NSSF Targets page. Here are two, high-contrast printable targets. With five (5) bullseyes per sheet, these are good for load development. They also work well at short range for pistol shooting.

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March 31st, 2015

NSSF Releases New Safety Video: “How to Talk to Your Kids”

Gun Safety Julie Golob NSSF Video

The National Shooting Sports Foundation (NSSF) has released a new, first-of-its-kind educational resource, the “How to Talk to Your Kids about Firearm Safety” video. The video, starring champion shooter Julie Golob, encourages parents to have “the talk” about firearm safety with their kids sooner rather than later, and provides tips for how to have a helpful discussion.

“As a mother, I know full well how challenging this conversation can be,” Golob said. “It’s crucial that parents set an example and teach their kids about firearm safety so children don’t learn about guns solely from what their friends say or what they see on video games and TV.”

“Too often, children don’t know what to do if they find a gun,” said Steve Sanetti, President and CEO of NSSF, which developed and sponsors the Project ChildSafe firearm safety education program. “This video opens a door for honest conversation and empowers parents to be the authority on gun safety for their kids, whether they have guns in their homes or not.”

The “How to Talk to Your Kids about Firearm Safety” video was created as a resource to start positive and constructive conversations by encouraging discussion rather than lecture, and helps parents responsibly demystify the subject of guns. For more information, visit Projectchildsafe.org.

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March 29th, 2015

Wind Reading Resources from JarHeadTop’s M.Sgt. Jim Owens

Readers often ask for a good, authoritative resource on doping the wind and reading mirage. Many Forum members recommended M.Sgt. Jim Owens’ Wind-Reading Guide. With 22 sets of wind charts, this is offered for $12.95 as a printed book or in CD format. Owens’ Reading the Wind and Coaching Techniques clearly explains how to gauge wind speeds and angles. Owens, a well-known High Power coach and creator of Jarheadtop.com, offers a simple system for ascertaining wind value based on speed and angle. The CD also explains how to read mirage — a vital skill for long-range shooters. In many situations, reading the mirage may be just as important as watching the wind flags. Owens’ $12.95 CD provides wind-reading strategies that can be applied by coaches as well as individual shooters.

As a separate product, Owens offers a Reading the Wind DVD for $29.95. This is different than the $12.95 book/CD. It is more like an interactive class.

Played straight through, the DVD offers about 75 minutes of instruction. M.Sgt. Owens says “You will learn more in an hour and fifteen minutes than the host learned in fifteen years in the Marine Corps shooting program. This is a wind class you can attend again and again. [It provides] a simple system for judging the speed, direction and value of the wind.” The DVD also covers mirage reading, wind strategies, bullet BC and more.

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March 27th, 2015

3 Targets, 400 yards, 4.37 Seconds — Offhand

Jerry Miculek — that name is synonymous with revolvers. But Jerry is also one heck of a rifleman, as he demonstrates in this video.

Jerry Miculek AR15 400 yards

Three Shots Standing at 400 Yards in 4.37 Seconds
For those of use who usually shoot from the bench, hitting a silhouette target at 400 yards from an standing position (unsupported) would be a big challenge. Here Jerry Miculek makes it look easy.

In this video, Jerry hits not one but THREE c-zone targets at 400 yards. And — get this — he does this in under 4.4 seconds starting with his rifle laying on a support. It took Jerry two tries (on his first run he hit 2 out of 3 in 4.65 seconds). On the second attempt (see video starting at 2:19), it takes Jerry just 4.37 seconds to shoulder his rifle, aim, and fire three shots, each hitting a separate steel target. Wow. That’s truly remarkable. Most of us would need ten seconds (or more) just to get the scope on the first target.

Jerry Miculek AR15 400 yards

Trust us folks, this ain’t easy. It takes remarkable marksmanship skills to shoot with this kind of precision at this kind of pace. As Jerry would say himself, “Not bad for an old guy who needs glasses”.

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March 26th, 2015

Shooting Science: Monitoring Brain Waves and Muscle Activity

“[Elite] shooters have this specific thing that happens in their brain when they are shooting well. Maybe you’d call it a ‘quiet time’. One interpretation is that it is a lack of self-instruction or analysis. Once you are an expert you really shouldn’t be [thinking] ‘don’t do this, don’t do that’.”

In this video from USA Shooting, a scientist uses brain wave (EEG) and muscle activity monitors to study the biomechanics and cognitive functions involved in competitive shooting. The study explores how elite shooters control their muscles and mind before executing a perfect shot.

In the video, USOC Sports Psychologist Lindsay Thornton works with pistol shooter Teresa Chambers to evaluate (and optimize) Teresa muscle and brain wave activity during shooting. One purpose of the study is to see how a shooter’s muscles function before, during and after a firing sequence. The goal is to use the muscles in the most efficient manner. This reduces fatigue and improves shot-to-shot consistency. Thorton says: “We are trying to define [muscle activity] efficiency with numbers so we can replicate that.”

Thorton is also exploring how a top shooter’s brain functions when he or she is “dialed in” and shooting most accurately. Thornton explains: “We are looking at EEG activity, which is brain wave activity. Research studies show that shooters have this specific thing that happens in their brain when they are shooting well. Maybe you’d call it a ‘quiet time’. One interpretation is that it is a lack of self-instruction or analysis. Once you are an expert you really shouldn’t be [thinking] ‘don’t do this, don’t do that’ — everything should be pretty automatic.” Interestingly, the test showed a specific pattern of Alpha band brain waves right before a trained shooter breaks the shot.

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March 25th, 2015

When the Worst Happens — Responding to Gunshot Injuries

We recently showed a video of an incident at a pistol match that easily could have resulted in the death of a range worker. If you watched that video (it’s all over the web this web), you’ll understand that one momentary oversight is all it takes to put someone in the hospital (or the morgue). That’s why shooters should be prepared for the worst. Get first-aid training, and carry a basic first-aid kit whenever you go to the range.

Carry a Basic First-Aid Kit
Shinnosuke Tanaka, reporter for RECOIL Magazine, offers some good advice: “OK, most of us have seen the [pistol match incident] video. YES, it is RSO’s fault not checking down range enough. BUT it’s your bullet that could hurt someone when it happen. So don’t let someone take care of safety for you, look around one more time after the command ‘Make ready’.”

Four basic firearms safety rules always apply. The Fourth Rule is: “Always be sure of your target and what is beyond it”. Shinnosuke adds: “My own fifth rule is ‘If there is doubt, don’t pull the trigger’.”

First Aid Kit Tannaka EMT

Shinnosuke cautions: “If you play with firearms you should know how to deal with gunshot wounds… Carry a simple medical kit. Here is my first aid kid, always carried on top of my shooting pack. Seek professional training and know how to use it. It’s your responsibility to stop the loss of your blood when an accident happens.”

Watch Gun Shot First Aid Video

If someone at a range is seriously injured by a gunshot, you should immediately summon emergency medical professionals. In addition, basic first aid can help stabilize the injured individual. This 55-minute video explains Basic First Aid for Gunshot Wounds:

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March 17th, 2015

NRA Junior Shooting Camp Opportunities this Summer

Junior Camp NRA

NRABlog.com story by Kyle Jillson
If you know a shooter aged 12-21 who would enjoy some shooting sports action this summer, the NRA is now accepting applications for its annual competitive Shooting Camps for Junior Shooters. These camps, run by the Coach Education Program, help young shooters develop their marksmanship skills. CLICK HERE for application info.

“These camps have everything you need to take your game to the next level,” said NRA National Coach Trainer Daniel Subia. “Each day will be filled with exercises designed to help you master your body positioning, breath, and trigger control to consistently shoot high scores. You’ll be tired at the end of each day, but you’ll leave a better shooter than you were before.”

Intermediate Junior Pistol Camp: June 26 – June 28
Held in Canton, Ohio, this camp is for beginning and intermediate shooters and is limited to 25 students. The camp registration deadline is June 1.

Intermediate Junior Rifle Camp: July 5 – July 10
Located in Camp Perry, Ohio’s Petraca Range, this camp features two admission periods for its 60 slots. The first admission period, open March 11 – April 30 is for junior shooters who have previously participated in an NRA Junior 3P or 4P Smallbore sectional match. The Second admission, open May 1, is open to all shooters.

Junior Advanced Competitive Smallbore Rifle Camp: July 6 – July 14

Held in Jericho, Vermont, this 9-day camp is a demanding training opportunity for advanced athletes and is limited to 20 students. The camp registration deadline is May 1. “[This camp] is like Top Gun for smallbore athletes. We take the best and make them better. We’re not leaving anything out. We will do everything possible to make sure that every marksman leaves this camp as a sharpshooter or better”, said Daniel Subia. “Attendees can expect a challenging, incredibly rewarding training experience that will prepare them for competition at the highest level.”

National Shooting Camp Junior Jericho Vermont

To learn more about these training camps and download the application package, visit the National Junior Shooting Camps webpage. Questions? Contact Daniel Subia at coaching[at]nrahq.org.

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March 10th, 2015

Help Kids — Become a Summer Camp Marksmanship Instructor

Many of us learned to shoot firearms while in the Boy Scouts or at a summer camp. To ensure that next generation of Americans learns about marksmanship and firearms safety in a positive way, it’s important to support summer camp shooting programs. The Civilian Marksmanship program is doing just that via a program that trains adults as summer camp marksmanship instructors.

CMP Master Riflery instructor NRA Boy Scouts BSA merit badge

CMP Master Riflery instructor NRA Boy Scouts BSA merit badgeCMP Camp Riflery Master Instructor Courses
Would you like to help young people learn about shooting? You can become a part of the Civilian Marksmanship Program’s (CMP) growing list of Camp Riflery Master Instructors by attending one of two Camp Riflery Master Instructor Workshops being offered in 2015. A workshop will be held at Camp Perry, OH, March 16-17, and in Anniston, AL, March 23-24. Camp Riflery programs are some of the most popular activities offered at summer camps around the country. There, boys and girls learn safe gun handling and marksmanship skills, while also being introduced to the stimulating sport of target shooting. Along the way, the juniors also develop valuable life skills that will be beneficial on their journey into adulthood.

CMP Master Riflery instructor NRA Boy Scouts BSA merit badge

This photo is from California’s Camp Josepho. This Boy Scout facility offers one of the BSA’s best marksmanship programs, a 5-day summer session that provides intensive training on Rifle and Pistol Shooting, Archery, and Tomahawk throwing. CLICK HERE for more information.

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March 3rd, 2015

Texas Triumph: 3600-Yard Shot with .375 CheyTac

3600 yard shot .375 cheytac texas

3600 yard shot .375 cheytac texas

They say “things are bigger in Texas”. Well shots are longer too. In this video, a shooter successfully hits a 1-MOA target at 3600 yards with a .375 CheyTac rifle. That required plenty of elevation to compensate for the bullet’s drop over its 2.045 mile trajectory. The shooter, Jim Spinella of New Jersey, needed a whopping 60.2 Mils of elevation (26.8 in rail, 22.6 in turret, 10.8 hold-over). Jim had to wait a long time to confirm the hit — with the metal gong situated more than than 2 miles from the firing line, it took the bullet 7.2 seconds to hit the target.

Big 350gr Bullets with a Wicked BC
The 3600-yard hit was made with CheyTac factory ammo using 350gr CNC-turned bullets. Spinella was impressed: “The ammo chronographed out at 3080 fps with velocity differences at no more the 7 fps, which was outstanding. We found the true BC over 3600 yards to average 0.810 (G1)”.

NOTE: You see three shots in the video, but Spinella took many more before a hit was achieved: “We peppered the 2 MOA area around the target with a couple of dozen rounds. We hit the rack the target is hanging on twice. This was a fun experience, and we took a lot of data away from it. We put a lot of work and planning into this in order to be in position to be lucky. So many things are ridiculously magnified at that distance. Every 1 mph change in wind [moves the bullet] about 6 feet. As the barrel heats up the velocity changes with it [and] 10 fps velocity differences, shot to shot, are almost 5 feet.”

This ultra-long-range adventure took place last September at the FTW Ranch in Texas. Spinella worked with a team of experts from Hill Country Rifles, builders of the custom .375 CheyTac rifle, to achieve a 3600-yard shot on a 36” round steel target. Hitting a target at 2.045 miles is no mean feat. That 36″ gong represents slightly less than 1 MOA at that range. A lot can happen to send a bullet off target during a 7.2 second flight.

Rifle: Hill Country Rifles custom .375 Cheytac,
Stiller Precision action, 29″ Krieger barrel
Optics: Schmidt & Bender 5-25X56mm PM-2 scope
Actual Measured Distance: 3606.41 Yards
Target: 36″ circular steel plate

Altitude: 2000 feet
Temp: 70 degrees
Elevation: 60.2 mil
Windage: 3.5 mil left

3600 yard shot .375 cheytac texas

CheyTac Caliber Comparison — .375 vs. .408
The shooter, Jim Spinella, prefers the .375 CheyTac to its .408-caliber Big Brother: “I shoot both the .408 and .375. Both are great ELR rounds and will get you out there a long way. In my experience, the .375 will get you out there a little bit further. My preference is the .375 Cheytac over the .408. This has nothing really to do with external ballistics. It has to do with fouling. My .408 will go from stellar accuracy to terrible between 40 and 45 rounds. It happens that quickly and accuracy returns after cleaning the barrel. I have never experienced this with the .375. After 100 rounds there is minimal copper fouling with the .375, but I clean around this round count. I don’t know why there is heavy cooper fouling in the .408, but it is common to this round and other shooters who shoot it regularly. That said, I lightly clean the .408 using Wipeout and go back to having fun with it after about 30 minutes.”

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February 28th, 2015

Brian “Gunny” Zins Explains Bullseye Pistol Fundamentals

Brian Gunny ZinsBrian “Gunny” Zins, 12-Time NRA National Pistol Champion, has authored an excellent guide to bullseye pistol shooting. Brian’s Clinic on the Fundamentals recently appeared in The Official Journal of the New York State Rifle & Pistol Association. The CMP scanned the story so you can read it online. CLICK HERE to read full article.

Top Tips from Brian Zins:

Trigger Movement: If trigger control is ever interrupted in slow fire the shot needs to be abored and the shot started over.

Relationship between Sight Alignment and Trigger Control: Often when the fundamentals are explained these two are explained as two different acts. Well, truth be told it’s really kind of hard to accomplish one without the other. They have a symbiotic relationship. In order to truly settle the movement in the dot or sights you need a smooth, steady trigger squeeze.

Trigger Finger Placement: Where should the trigger make contact on the finger? The trigger should be centered in the first crease of the trigger finger. Remember this is an article on Bullseye shooting. If this were an article on free pistol or air pistol it would be different.

Proper Grip: A proper grip is a grip that will NATURALLY align the gun’s sights to the eye of the shooter without having to tilt your head or move your or move your wrists around to do that. Also a proper grip, and most importantly, is a grip that allows the gun to return to the same position [with sights aligned] after each and every shot. The best and easiest way to get the proper grip, at least a good starting postion… is with a holster. Put your 1911 in a holster on the side of your body[.] Allow your shooting hand to come down naturally to the gun.

In recent years, Brian “Gunny” Zins has been shooting 1911s crafted by Cabot Guns.

Brian “Gunny” Zins currently holds 25 National Records.

Brian “Gunny” Zins

NRA Nat’l Pistol Champion: 1996, 1998, 2001, 2000, 2003, 2004, 2005, 2007, 2008, 2010, 2012, 2013

NRA .22 LR Nat’l Champion: 2003, 2004, 2006, 2008, 2010

NRA Centerfire Nat’l Champion: 1992, 1996, 1998, 2001, 2002, 2003, 2004, 2006

NRA .45 Nat’l Champion: 1996, 2001, 2005, 2007, 2009

NRA Regular Service Nat’l Champion: 1996, 1998, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008

NRA Civilian Nat’l Champion: 2008, 2009, 2010

NRA Nat’l Trophy Individual: 1998, 2003

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February 20th, 2015

Win a Training Day with Olympic Shooting Coaches

eley national team rimfire smallbore training

Getting tutored by Olympic-class experts — now that’s a rare opportunity in the shooting world. ELEY Ltd., makers of precision rimfire ammo, has announced a special contest. Two lucky marksmen (one pistol shooter and one rifle shooter) will win the chance to train with the U.S. National Team at the Olympic Training Center in Colorado Springs. All ammunition for the one-day training session (in June, 2015) will be supplied by ELEY. (The winners must supply their own firearm.) The lucky winners will even be able to use the elite Olympic Training Center strength/conditioning facilities.

Training day sessions will be conducted by top coaches/atheletes from the U.S. National squad. Rifle coaches may include: Bryant Wallizer, Thomas Csenge, Michael Liuzza, Justin Tracy (2013 Prone National Champion), Dempster Christenson, Sarah Beard, Sarah Scherer, Emily Holsopple, Amy Sowash, Reya Kempley, and former National Rifle Coach Dave Johnson.

Pistol coaches may include: Keith Sanderson, Nick Mowrer, Jason Turner, Teresa Chambers, Morgan Wallizer (2004 rifle Olympian now training pistol), National Pistol Coach Sergey Luzov.

eley national team rimfire smallbore training

How to Enter Contest
For more information, or to enter the Training Day Contest, visit ELEY’s Training Contest Page on Facebook. NOTE — the deadline for contest entries is March 16, 2015.

eley national team rimfire smallbore training

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February 18th, 2015

Click No Bang — Dry-Fire Training with Kirsten

kirsten weiss dry fire anschutz smallbore

Kirsten Joy Weiss has just released a new video on Dry-Fire practice. Dry-Fire is a method of training without a live round in the chamber. Dry-Firing is effective, Kirsten explains, because “it eliminates all the extra noise and messages that you get when you fire a live round. Without recoil, without the sound of a shot going off etc., all you hear is the click of the trigger. This allows you to focus on your sight picture and your trigger press.” This the lastest installment in Kirsten’s ‘How to Shoot Awesomely’ series. Kisten says: “I hope it helps you, and keep on aiming true!”

kirsten weiss dry fire anschutz smallbore

Dennis DeMille High PowerThe Benefits of Dry-Fire Training
If you are not doing Dry-Fire practice yet, then it’s time to start. Dry-Fire training is essential to the sling disciplines, and very useful for F-Class. Dennis DeMille, a national Service Rifle Champion, told us that, for every minute he spent in actual competition, he would spend hours practicing without ammunition. While in the USMC, Dennis would practice in the barracks, working on his hold and dry-firing:

“The most important thing is to spend time off the range practicing. Most of what I learned as a High Power shooter I learned without ammunition — just spending time dry firing and doing holding exercises. Holding exercises will really identify the weak parts of your position. The primary purpose of dry firing is to get you used to shooting an empty rifle. If you can shoot a loaded rifle the same way you shoot an empty rifle then eventually you will become a High Master.”

Dry-Fire Training Can Benefit Benchrest Shooters
What about benchrest? Well, we’ve found that Dry-Fire sessions can even benefit benchresters — it can help reveal flaws in your trigger technique, or inconsistencies in the way you address the rifle from shot to shot. With the gun set up with your front rest and rear bag, if you see the scope’s cross-hairs wiggle a lot when you pull the trigger, you need to work on your technique. Also, dry-fire practice can help you learn to work the bolt more smoothly so you don’t disturb the gun on the bags.

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February 17th, 2015

Brain Teaser: Do You Know the Rule of the Square?

wind drift wind reading 6mmbr rule of the squareHorizontal Wind-Drift vs. Distance
OK, here’s a challenge question for you.
Let’s see if you get it right.

Q: If the wind is blowing 10 mph from 9 o’clock and if my horizontal wind deflection is 0.7 inches at 100 yards, what is the horizontal drift at 1000 yards?

You may be thinking, “Well, since the target is ten times more distant, the wind-drift should be around 7 inches, maybe a little more since the bullet will be slowing down.” That sounds reasonable, right?

WRONG.

As you move from near to far, the increase in lateral deflection (from a 90° crosswind) is (roughly speaking) a function of the square of the multiple of distance. If your target is two times farther away, you use the square of two, namely four. If your target is five times farther away, you use the square of five, or twenty-five. In this example, the increased wind drift (from 100 to 1000 yards) is at least 0.7″ times (10 X 10) — over 70 inches (give or take a few inches depending on bullet type). We call that the Rule of the Square. This Rule lets you make a quick approximation of the windage correction needed at any yardage.

Precision Shooting and the Rule of the Square
I was going through some back issues of Precision Shooting Magazine and found many references to the Rule of the Square. This made me curious — I wondered how well the Rule really stacked up against modern ballistics programs. Accordingly, I ran some examples through the JBM Ballistics Trajectory Calculator, one of the best web-based ballistics programs. To my surprise, the Rule of the Square does a pretty good job of describing things.

EXAMPLE ONE — .308 Win (100 to 400 Yards)
For a 168gr Sierra MK (.308), leaving the muzzle at 2700 fps, the JBM-predicted values* are as follows, with a 10 mph, 9 o’clock crosswind (at sea level, 65° F, Litz G7 BC):

Drift at 100: 0.8 MOA (0.8″)
Drift at 200: 1.6 MOA (3.3″)
Drift at 400: 3.4 MOA (14.4″)

Here you can see how the Rule of the Square works. The rule says our drift at 200 yards should be about FOUR times the drift at 100. It the example above, 0.8″ times 4 is 3.2″, pretty darn close to the JBM prediction of 3.3″. Quoting Precision Shooting: “Note that the deflections at 100 yards are typically a quarter of those at 200; lateral deflections increase as the square of the range”. Precision Shooting, June 2000, p. 16.

EXAMPLE TWO — .284 Win (100 to 1000 Yards)
For a .284 Win load, with the slippery Berger 180gr Target Hybrids, the Rule of the Square still works. Here we’ll input a 2750 fps velocity, Litz G7 BC, 10 mph, 9 o’clock crosswind, (same 65° temp at sea level). With these variables, JBM predicts:

Drift at 100: 0.5 MOA (0.5″)
Drift at 500: 2.5 MOA (13.3″)
Drift at 1000: 5.9 MOA (61.3″)

Again, even with a higher BC bullet, at 1000 yards we end up with something reasonably close to the 100-yard deflection (i.e. 0.5″) multiplied by (10×10), i.e. 50 inches. The Rule of the Square alerts you to the fact that the effects of crosswinds are MUCH greater at very long range. In this example, our JBM-calculated drift at 1000 is 61.3″ — that’s over 100 times the 100-yard lateral drift, even though the distance has only increased 10 times.

Note that, even with a 5 mph 90° sidewind, the “Rule of the Square” still applies. The 1000-yard lateral deflection in inches is still over 100 times the lateral deflection at 100 yards.


Why This All Matters (Even in the Age of Smartphones)
wind drift wind reading 6mmbr rule of the squareNow, some would say, “Why Should I Care About the Rule of the Square? My iPhone has a Ballistics App that does all my thinking for me”. Fair enough, but knowledge of this basic Rule of the Square enables a shooter to make an informed guess about necessary windage even without a come-up sheet, as long as he knows the distance AND can fire a sighter at 100 or 200 yards as a baseline.

For example, if I see empirically that I need 1″ windage correction at 100 yards, then I know that at 600 yards I need at least roughly (6 x 6 x 1″) or 36 total inches of drift correction, or 6 MOA. (To be precise, 1 MOA = 1.047″ at 100 yards). I can figure that out instantly, even without a ballistics chart, and even if my Smartphone’s battery is dead.

*Values shown are as displayed on the JBM-figured trajectory tables. The numbers can be slightly imprecise because JBM rounds off to one decimal place for both inches and MOA.

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