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August 16th, 2017
CLICK HERE to see full-screen version of Wind Plot.
The Battle of Nations begins. Today is Day 1 of international team competition at the 2017 F-Class World Championships (FCWC) in Ottawa, ON, Canada. Talented teams, in their nation’s colors, will be competing for glory and national pride.
Team shooting is very different than individual competition. Typically a team coach makes the wind calls for the shooters. In some cases (where the rules allow), the wind coach even dials elevation and windage changes for the active shooter. For the wind coach to do his job effectively, he must follow the changes in the wind and determine what the correct wind call should have been for each shot. (In other words — what was the “right call”)
Past F-TR USA Nat’l Champ Bryan Litz was wind coach for the winning 4-man LUM F-TR Team at the 2017 Canadian F-Class Championships, which preceded the FCWC Worlds. Here Bryan explains how he uses a Wind Plot to make better wind calls, helping his team-mates maximize their scores.
Wind Plot Methodology by Bryan Litz
The wind plot I use is a running history of what the correct wind call was for every shot fired. The more you shoot, the more history you have in a condition, and I find that very useful information. This kind of plot IS NOT showing where the bullet hit, and is NOT showing what you held. It’s showing what you should have held to center each shot. IMO, this is the most valuable information to have when guessing where to hold next for each shot. Here are some key points:
1. I always look for blocks of stable conditions to shoot in and wait out the rest.
2. If the wind plot shows drastic changes, either I’m not picking the right time to shoot or it’s just a really unstable wind condition.
3. When you see many shots using the same hold (e.g. Robby’s 700m and 900m strings on plot), it can indicate very fast shooting and fast pit service.
Q. What are the numbers and Markings on this Wind Plot?
Litz: The wind plot represents the rings on the target. Left 2 for example, is the 5 line on the international target, while Left 2 is the 10 line on the USA target. F-Class shooters and coaches talk about wind holds in relation to these rings. A Left 2 hold isn’t left 2 MOA or 2 MILS, it’s the second ring from center. The vertical lines on the plot represent the rings going out from center, 4 or 5 in each direction. A left or right 5 hold is edge of black on the int’l target.
Q: What Does this Specific Plot Reveal?
Litz: Looking at the plot, from left to right is 700m, 800m, and 900m that we shot progressively through the day. Top to bottom shows each shooter in sequence (shooters names are shown by their blocks). To the right I note what was on the gun for that shooter, and note when it changes. Often times we run the same wind on the gun for several shooters but if it changes, I note what the new windage is and continue on. For example if we’re settled into a condition where we’re shooting Vs with a right 3 hold, I might adjust the scope 1 MOA right because a right 3 hold is equal to 1 MOA. So we can move the scope and start shooting with a center hold.
Q. Are you Plotting Where the Bullet Hits?
Litz: Not exactly. This kind of plot IS NOT specifically showing where the bullet hit, and IS NOT showing what the shooter held. It’s showing what the shooter should have held to center each shot. IMO, this is the most valuable information to have when guessing where to hold next for each shot.
On each shot, the shooter or coach takes a guess about where to hold, and fires the shot. If the bullet hits the center, you plot the point right where you held because it was the correct hold. However, if you miss the call, you plot what hold was required to put that shot in the center. For example if you shoot a right 3 and hit where you held, the correct call would have been “center”. In this way, you’re building a history of what you should have done, which may or may not be what you actually did. This shows you the trends, and brackets which can be used to make future decisions.
Q: Is this Type of Wind Plot Something New?
Litz: I didn’t invent this method, it’s been around a long time. Vertical can be plotted the same way. In team matches, we have a plotter who is advising on elevation trends and suggesting corrections. But, as wind coach, my job is the horizontal so I only keep the wind plot. I have learned lots of strategies from my coaches Emil Praslick and Steve Hardin.
There are many ways to plot and many standard work sheets for this. They’re all tools and the key is to find something that works for you in different situations. I don’t keep a plot when I am personally behind the trigger string firing because I lose more points when I take the time to do it vs. just shooting fast. When pair firing or coaching, I can keep the wind plot without compromising the shooting.
Team Australia used plots and comms linking coaches to help win the 2013 F-Open Team World Championship. We expect other teams will follow suit in Canada in 2017.
Know Your Goal — Keep It Simple
Know your goal of plotting. The simplest plot is where you write the shot number where it hit on a target face. This kind of plotting is useful for evaluating shooter performance because it shows how big the group is (in particular the vertical dispersion). However keeping a plot like this does little to help you figure out the wind. It just shows you what shots you messed up on. It does nothing to help you find the center. [Editor: That’s a whole different matter with many variables.] The wind plot I use is a running history of what the correct wind call was for every shot fired. The more you shoot, the more history you have in a condition, and I find that very useful information.
August 12th, 2017
The F-Class World Championships (FCWC) commence today at the Connaught Ranges outside Ottawa, Ontario, Canada. We wish good luck to all the competitors. Based on the conditions at the recent Canadian F-Class National Championships, conditions could be challenging.
F-Class World Championships EVENT SCHEDULE:
Friday, August 11 (REST DAY – RANGE CLOSED)
Competitor Check-In for FCWC; Rifle Inspection; International Teams Reception
Saturday, August 12: Opening Ceremonies; ICFRA FCWC (Individual)
Sunday, August 13: ICFRA FCWC (Individual)
Monday, August 14: ICFRA FCWC (Individual); Awards Prize Giving
Tuesday, August 15: TEAM PRACTICE DAY
Wednesday, August 16: ICFRA FCWC (Teams)
Thursday, August 17: ICFRA FCWC (Teams): Awards Prize Giving & Closing Ceremonies
Tips for Success at the F-Class Worlds — #1, Avoid Train Wrecks
As an assist to all the competitors, we’re repeating an article by Bryan Litz, which many have found very helpful — how to avoid “Train Wrecks” at major championships.
When you have a major, critical problem at a shooting match, i.e. a “train wreck”, this can be the end of your weekend. In this article, Ballistics Guru Bryan Litz talks about “train wrecks” — the big disasters (such as equipment failures) that can ruin a whole match. A recent USA F-TR Champion, Bryan illustrates the types of “train wrecks” that commonly befall competitors, and he explains how to avoid these “unmitigated disasters”.
 Train Wrecks (and How to Avoid Them)
by Bryan Litz of Applied Ballistics LLC.
Success in long range competition depends on many things. Those who aspire to be competitive are usually detail-oriented, and focused on all the small things that might give them an edge. Unfortunately it’s common for shooters lose sight of the big picture — missing the forest for the trees, so to speak.
Consistency is one of the universal principles of successful shooting. The tournament champion is the shooter with the highest average performance over several days, often times not winning a single match. While you can win tournaments without an isolated stellar performance, you cannot win tournaments if you have a single train wreck performance. And this is why it’s important for the detail-oriented shooter to keep an eye out for potential “big picture” problems that can derail the train of success!
Train wrecks can be defined differently by shooters of various skill levels and categories. Anything from problems causing a miss, to problems causing a 3/4-MOA shift in wind zero can manifest as a train wreck, depending on the kind of shooting you’re doing.
Below is a list of common Shooting Match Train Wrecks, and suggestions for avoiding them.
1. Cross-Firing. The fastest and most common way to destroy your score (and any hopes of winning a tournament) is to cross-fire. The cure is obviously basic awareness of your target number on each shot, but you can stack the odds in your favor if you’re smart. For sling shooters, establish your Natural Point of Aim (NPA) and monitor that it doesn’t shift during your course of fire. If you’re doing this right, you’ll always come back on your target naturally, without deliberately checking each time. You should be doing this anyway, but avoiding cross-fires is another incentive for monitoring this important fundamental. In F-Class shooting, pay attention to how the rifle recoils, and where the crosshairs settle. If the crosshairs always settle to the right, either make an adjustment to your bipod, hold, or simply make sure to move back each shot. Also consider your scope. Running super high magnification can leave the number board out of the scope’s field view. That can really increase the risk of cross-firing.
2. Equipment Failure. There are a wide variety of equipment failures you may encounter at a match, from loose sight fasteners, to broken bipods, to high-round-count barrels that that suddenly “go south” (just to mention a few possibilities). Mechanical components can and do fail. The best policy is to put some thought into what the critical failure points are, monitor wear of these parts, and have spares ready. This is where an ounce of prevention can prevent a ton of train wreck. On this note, if you like running hot loads, consider whether that extra 20 fps is worth blowing up a bullet (10 points), sticking a bolt (DNF), or worse yet, causing injury to yourself or someone nearby.
3. Scoring/Pit Malfunction. Although not related to your shooting technique, doing things to insure you get at least fair treatment from your scorer and pit puller is a good idea. Try to meet the others on your target so they can associate a face with the shooter for whom they’re pulling. If you learn your scorer is a Democrat, it’s probably best not to tell Obama jokes before you go for record. If your pit puller is elderly, it may be unwise to shoot very rapidly and risk a shot being missed (by the pit worker), or having to call for a mark. Slowing down a second or two between shots might prevent a 5-minute delay and possibly an undeserved miss.
 4. Wind Issues. Tricky winds derail many trains. A lot can be written about wind strategies, but here’s a simple tip about how to take the edge off a worse case scenario. You don’t have to start blazing away on the command of “Commence fire”. If the wind is blowing like a bastard when your time starts, just wait! You’re allotted 30 minutes to fire your string in long range slow fire. With average pit service, it might take you 10 minutes if you hustle, less in F-Class. Point being, you have about three times longer than you need. So let everyone else shoot through the storm and look for a window (or windows) of time which are not so adverse. Of course this is a risk, conditions might get worse if you wait. This is where judgment comes in. Just know you have options for managing time and keep an eye on the clock. Saving rounds in a slow fire match is a costly and embarrassing train wreck.
5. Mind Your Physical Health. While traveling for shooting matches, most shooters break their normal patterns of diet, sleep, alcohol consumption, etc. These disruptions to the norm can have detrimental effects on your body and your ability to shoot and even think clearly. If you’re used to an indoor job and eating salads in air-conditioned break rooms and you travel to a week-long rifle match which keeps you on your feet all day in 90-degree heat and high humidity, while eating greasy restaurant food, drinking beer and getting little sleep, then you might as well plan on daily train wrecks. If the match is four hours away, rather than leaving at 3:00 am and drinking five cups of coffee on the morning drive, arrive the night before and get a good night’s sleep.”
Keep focused on the important stuff. You never want to lose sight of the big picture. Keep the important, common sense things in mind as well as the minutia of meplat trimming, weighing powder to the kernel, and cleaning your barrel ’til it’s squeaky clean. Remember, all the little enhancements can’t make up for one big train wreck!
August 6th, 2017
“Science tells us that exposure to continuous noise of 85 dB for eight hours is enough to cause permanent hearing loss, and worse, spikes of 130 dB and more can result in permanent hearing damage instantly.”
Source: NRA Blog.
 The Risk of Hearing Loss
Hearing loss can be progressive and irreversible. If you are a shooter, this is serious business. As the NRA Blog cautions: “You may not even realize you’re harming your hearing. Hearing loss occurs gradually, and can go effectively unnoticed until symptoms become severe. By then, the damage is done.”
Nobody wants to go deaf. But we often see shooters without effective hearing protection when they are walking around a few yards behind the firing line. That’s bad — even if you are away from the firing line, gunshot noises can damage your hearing. You MUST use effective hearing protection every time you go to the range. Good foam earplugs costs mere pennies but they can prevent deafness in your later years. Many folks also wear muffs over plugs.
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Sound Levels for Common Noises:
9mm Luger pistol: 160 dB
Jet aircraft engine (near): 140 dB
.22 LR pistol: 134 dB
Normal human pain threshold: 120 dB
Noisy Nightclub: 110 db
Riding Motorcycle at 65 mph: 103 db
Power Lawnmower: 95 dB
Hearing damage possible: 85 dB (sustained for 8+ hours)
Ringing Telephone: 80 dB
Normal conversation: 60 dB |
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The Myth of the “Quiet” .22 LR
The NRA Blog notes that “many rimfire shooters, particularly those using the beloved .22 Long Rifle cartridge, argue that the small .22 LR caliber doesn’t produce enough sound to damage your hearing”. So, is that really true … or is it a myth?
In fact, a .22 LR can be much louder than you think — a .22 LR pistol can produce sound levels of 134 dB. That’s well above the normal human pain threshhold.
Highest Protection NRR 34dB-Rated Ear Muffs
For under $20.00 you can buy quality ANSI-approved muffs with a 34dB Noise Reduction Rating — the best you can get. Chose the Bright Yellow TR Industrial Muffs at $13.48, or the dark green Walker EXT Range Muffs for $13.99. Both products have padded head-bands which retract. If you prefer “basic black”, consider the $14.85 ClearArmor Muffs, Amazon’s #1 Best Seller among safety earmuffs.
Howard Leight MAX NRR33 Earplugs, Just $7.39 for 50 Pairs.
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20 Pairs |
50 Pairs |
These Howard Leight NRR33 Max plugs are your Editor’s favorite foam earplugs. Between shooting, motorcycling and mowing lawns, I probably have Max plugs in my ears 2-3 days a week. This is a very good price for a bulk pack of 50 pairs. And if you act soon, you can get free shipping to boot.
August 5th, 2017
The movie “The Patriot” gave us the phrase “Aim small, miss small”. While that’s a good mantra, aiming strategies for long-range competition are a bit more complicated, as this article explains…
The The F-Class World Championships (FCWC) in Canada are just one week away. This August 11-17, the world’s top F-Class shooters will gather at the Connaught Ranges outside Ottawa, Ontario. Here are some tips that can help F-TR and F-Open shooters aim more precisely, and achieve higher scores. F-Class ace Monte Milanuk reviews reticle choices and strategies for holding off.
In our Shooters Forum, one newcomer wanted some advice on selecting a reticle for F-Class optics. He wondered about the advantage of Front (first) Focal Plane (FFP) vs. Second Focal Plane scopes and also wondered if one type of reticle was better for “holding off” than others.
In responding to this question, Forum regular Monte Milanuk provided an excellent summary of aiming methods used in F-Class. For anyone shooting score targets, Monte’s post is worth reading:
Aiming Methods for F-Class (and Long-Range) Shooting — by Monte Milanuk
 F-Class is a known-distance event, with targets of known dimensions that have markings (rings) of known sizes. Any ‘holding off’ can be done using the target face itself. Most ‘benefits’ of Front (first) focal plain (FFP) optics are null and void here — they work great on two-way ranges where ‘minute of man’ is the defining criteria — but how many FFP scopes do you know of in the 30-40X magnification range? Very, very few, because what people who buy high-magnification scopes want is something that allows them to hold finer on the target, and see more detail of the target, not something where the reticle covers the same amount of real estate and appears ‘coarser’ in view against the target, while getting almost too fine to see at lower powers.
Whether a person clicks or holds off is largely personal preference. Some people might decline to adjust their scope as long as they can hold off somewhere on the target. Some of that may stem from the unfortunate effect of scopes being mechanical objects which sometimes don’t work entirely as advertised (i.e. one or two clicks being more or less than anticipated). Me personally, if I get outside 1-1.5 MOA from center, I usually correct accordingly. I also shoot on a range where wind corrections are often in revolutions, not clicks or minutes, between shots.
Some shooters do a modified form of ‘chase the spotter’ — i.e. Take a swag at the wind, dial it on, aim center and shoot. Spotter comes up mid-ring 10 at 4 o’clock… so for the next shot aim mid-ring 10 at 10 o’clock and shoot. This should come up a center X (in theory). Adjust process as necessary to take into account for varying wind speeds and direction.
 Others use a plot sheet that is a scaled representation of the target face, complete with a grid overlaid on it that matches the increments of their optics — usually in MOA. Take your Swag at the wind, dial it on, hold center and shoot. Shot comes up a 10 o’clock ‘8’… plot the shot on the sheet, look at the grid and take your corrections from that and dial the scope accordingly. This process should put you in the center (or pretty close), assuming that you didn’t completely ignore the wind in the mean time. Once in the center, hold off and shoot and plot, and if you see a ‘group’ forming (say low right in the 10 ring) either continue to hold high and left or apply the needed corrections to bring your group into the x-ring.
Just holding is generally faster, and allows the shooter to shoot fast and (hopefully) stay ahead of the wind. Plotting is more methodical and may save your bacon if the wind completely changes on you… plotting provides a good reference for dialing back the other way while staying in the middle of the target. — YMMV, Monte
July 27th, 2017
We know that many of our readers will be heading to Canada soon to attend the F-Class World Championships at the Connaught Ranges outside Ottawa. If you’ll be flying North in August, or venturing to another destination by air, you need to be careful when transporting firearms through airports both in the USA and in other countries. It is important that you comply with all Homeland Security, TSA, and Airline policies when transporting guns and ammunition. Following the rules will help ensure you (and your gear) make it to your destination without hassles, delays or (God forbid), confiscations.
To help our readers comply with rules and regulations for air travel, we offer these guidelines, courtesy “Ron D.”, a member of our Shooters’ Forum. Before he retired, Ron D. served as a Police Officer assigned to Chicago’s O’Hare airport. Here Ron offers some very important advice for shooters traveling with firearms and expensive optics.
 First, Ron explains that airport thieves can spot bags containing firearms no matter how they are packaged: “Don’t think you’re safe if your guns are placed in cases designed for golf clubs or trade show items. Baggage is X-Rayed now and cases are tagged with a special bar code if they contain firearms. It doesn’t take long for bad guys to figure out the bar coding for firearms.”
Carry-On Your Scopes and Expensive Items
Ron advises travelers to avoid placing very expensive items in checked baggage: “When traveling by air, carry on your rangefinder, spotting scope, rifle scope, medications, camera, etc. You would be surprised at the amount of people that carry-on jeans and shirts, but put expensive items in checked baggage. Better to loose three pairs of jeans than some expensive glass.”
Mark Bags to Avoid Confusion
Ron notes that carry-on bags are often lost because so many carry-on cases look the same. Ron reports: “People do accidentally remove the wrong bag repeatedly. I frequently heard the comment, ‘But it looks just like my bag.’ When de-planing, keep an eye on what comes out of the overhead that your bag is in. It’s easy to get distracted by someone that has been sitting next to you the whole flight. I tie two streamers of red surveyors’ tape on my carry-on bag.” You can also use paint or decals to make your carry-on bag more distinctive.
Many readers will fly to Ottawa, ON, Canada in two weeks to attend the F-Class World Championships.
Choosing a Rifle Transport Case
Ron advises: “Buy the best [rifle case] that you can afford. Don’t cry when your $3,000+ Benchrest rifle has a cracked stock or broken scope. Think about what it would be like to travel across the country (e.g. to Montana or the Cactus Classic) and arrive with a damaged rifle. Remember the Samsonite commercial. (For you younger shooters, it shows a monkey throwing the suitcase around in his cage at the zoo.) Baggage handling is NOT a fine art. There is no guarantee that your rifle case will be on top of all the other baggage. Then there is shifting of baggage in the belly of the plane. Ponder that for a while. Rifle and pistol cases must be locked. It doesn’t take a Rocket Scientist to figure out that a simple pry tool will open most case locks. There is not much that you can do to disguise a rifle case. It is what it is, and opportunists know this. Among thieves, it doesn’t take long for the word to get around about a NEW type of case.”
This Plano Double Scoped Rifle Case offers the functionality and durability of an SKB-type hard case for HALF the money. This is now just $111.19, while the equivalent SKB is around $240.00.
General Advice for Air Travelers
Ron cautions: “Keep your hands on your items before boarding. One of the most often heard comments from theft victims was, ‘I just put my computer down for a minute while I was on the phone.’ Also, get to the baggage claim area quickly. If your family/friends can meet you there, so can the opportunists. Things do get lost in the claim area. Don’t be a Victim. Forewarned is forearmed.”
July 18th, 2017
AccurateShooter Forum member John H. of New Mexico (aka “Skratch”) has created an impressive mobile shooting bench that he can haul with his ATV. This trailer-mounted, movable bench is built on a central tubular spine that also serves as the tongue for the trailer, which attaches to a standard hitch. The bench offers two (2) shooting positions so it works for both left-handed and right-handed shooters.
Up front, for storage, a surplus .50-Cal ammo can is secured to the trailer frame. The V-shaped middle section of the wood benchtop looks to be reinforced with a metal stiffener frame on the underside. The front section of the bench is supported by twin tubular uprights attached to the box-section axle housing. The two wooden bench-style seats (on left and right) ride on a cross-tube. At the ends of that cross-tube are adjustable legs for additional support.
Great Rig for New Mexico Varmint Hunting
There are plenty of great varmint hunting areas in Skratch’s home state of New Mexico — you’ll find some huge prairie dog fields there. But to get the best results on a varmint-hunting field session, you need a solid shooting station that can be easily hauled to new locations as needed. It looks like John (aka “Scratch”) has come up with an outstanding “War Wagon” for his New Mexico varmint safaris.
Click on image frames to see full-size photos
Some readers wanted to know how John’s War Wagon is positioned in the field and if it is ever detached from John’s ATV. John answers: “We do unhook the 4-wheeler for target-checking unless we have an extra along which is usually the case. That way we can level the table front to rear. We have an umbrella from a patio table to provide shade on extra warm days.”
War Wagon Construction Details
John told us: “My brother-in-law and I built this mobile bench a few years ago. The axle, wheels and tire are a tag axle from a small Chevy car, obtained from a salvage yard for about $35-$40 a decade ago. The tubular frame is drill stem, while the bench-top and seats are 3/4′” plywood. Under the plywood we fitted rails so we can slide our target stand under the benchtop for secure travel. The total cost for everything (including storage box) was about $250-$300.”
We set the bench and seat heights so that, with adults, the rifle sets straight level to the shoulder. For the smaller ‘younguns’ we just use a sofa pillow to raise them up. (Yes, adjustable seat heights would be great.) The ammo box holds our rifle rest, sand bags, spotting scope, and miscellaneous gear. Options are a couple of lawn chairs, and a cooler of brew (for after the shooting is done).
July 13th, 2017
 Like crosswords? Like guns? Well, thanks to Shooting Sports USA (SSUSA), you can try a crossword puzzle that tests your knowledge of gun stuff and competitive shooting. In the February 2013 digital edition of Shooting Sports USA magazine, you’ll find a crossword puzzle created just for shooters. There are some easy items, such as the location of the annual NRA National Pistol Championships (see story above). Other entries are more difficult, and may require some research. To print the crossword puzzle before you start working, click this Page 12 link, and then select the print icon. Spoiler alert — all the answers appear on PAGE 14 of the same February issue of SSUSA.
NOTE: These pages may be slow to load, but don’t fret, they WILL appear if you’re patient.
CLICK HERE for Crossword Puzzle Answers.
July 5th, 2017
The data-packed July issue of Shooting Industry magazine reveals key gun industry metrics — such as background checks, financial results from publicly-traded gun-makers, and the latest U.S. firearms manufacturing production data. The annual U.S. Firearms Today Report presents a comprehensive review of gun industry activity, including data on firearm production by caliber, shifts in export/import totals and the top 25 U.S. firearm manufacturers from 2015 (the latest data available).
As indicated by the ATF’s 2015 Annual Firearms Manufacturing and Export, the industry rebounded across several categories after a challenging 2014. Total firearms production increased from 8,692,461 in 2014 to 8,911,530 in 2015, growth of 2.5 percent. For the eighth year in a row, Ruger was the top overall U.S. firearms manufacturer with 1,667,820 firearms produced in 2015, while Smith & Wesson and Remington were the leading handgun and long-gun manufacturers, respectively. One notable trend is that Savage Arms significantly increased its production output compared to other leading rifle-makers.
Here are the top three rifle makers in 2015 with percentage change from 2014:
• Remington: 774,180 (-16.7%) | Ruger: 662,444 (-6.2%) | Savage Arms: 381,695 (+24.8%)
Gun Sales Trends in 2017 Compared to 2015
The Firearms Today Report reports that, contrary to some perceptions, gun sales remain strong: “Comparing the first five months of 2017 to 2015 (which was the second-largest year for U.S. firearms manufacturing), the industry is performing well. NICS background checks increased by 6.7 percent (from 5,427,494 to 5,793,571) from January through May 2017 compared to the corresponding months in 2015.”
The lastest issue of Shooting Industry (and all 2017 and 2016 monthly issues) can be accessed in their entirety online at www.shootingindustry.com/digital-version. CLICK HERE for July 2017 Digital Edition.
Story Lead from EdLongrange. We welcome reader submissions.
June 20th, 2017
 We know many of our readers aren’t 100% clear on the difference between a secant ogive bullet and a tangent ogive bullet. Add the “blended” or “hybrid” ogive into the design equation and you add to the confusion. In this article, Berger Ballistician Bryan Litz, explains the characteristics of the three popular ogive types: tangent, secant, and hybrid.
In discussions of ballistics, you’ll see references to “tangent” and “secant” bullet shapes. For many readers, these terms can be confusing. To add to the confusion, bullet makers don’t always identify their projectiles as secant or tangent designs. This article provides a basic explanation of tangent and secant designs, to help you understand the characteristics of both bullet shapes.
Tangent vs. Secant vs. Hybrid
Most match bullets produced today use a tangent ogive profile, but the modern VLD-style bullets employ a secant profile. To further complicate matters, the latest generation of “Hybrid” projectiles from Berger Bullets feature a blended secant + tangent profile to combine the best qualities of both nose shapes. The secant section provides reduced drag, while the tangent section makes the bullet easier to tune, i.e. less sensitive to bullet seating depth position.
Berger Bullets ballistician Bryan Litz explains tangent and secant bullet ogive designs in a glossary section of his Applied Ballistics website, which we reprint below. Bryan then explains how tangent and secant profiles can be combined in a “hybrid” design.
How Bullet Ogive Curves are Defined
While the term “ogive” is often used to describe the particular point on the bullet where the curve reaches full bullet diameter, in fact the “ogive” properly refers to the entire curve of the bullet from the tip to the full-diameter straight section — the shank. Understanding then, that the ogive is a curve, how is that curve described?
LITZ: The ogive of a bullet is usually characterized by the length of its radius. This radius is often given in calibers instead of inches. For example, an 8 ogive 6mm bullet has an ogive that is a segment of a circular arc with a radius of 8*.243 = 1.952”. A .30-caliber bullet with an 8 ogive will be proportionally the same as the 8 ogive 6mm bullet, but the actual radius will be 2.464” for the .30 caliber bullet.
For a given nose length, if an ogive is perfectly tangent, it will have a very specific radius. Any radius longer than that will cause the ogive to be secant. Secant ogives can range from very mild (short radius) to very aggressive (long radius). The drag of a secant ogive is minimized when its radius is twice as long as a tangent ogive radius. In other words, if a tangent ogive has an 8 caliber radius, then the longest practical secant ogive radius is 16 calibers long for a given nose length.”
Ogive Metrics and Rt/R Ratio
LITZ: There is a number that’s used to quantify how secant an ogive is. The metric is known as the Rt/R ratio and it’s the ratio of the tangent ogive radius to the actual ogive radius for a given bullet. In the above example, the 16 caliber ogive would have an Rt/R ratio of 0.5. The number 0.5 is therefore the lowest practical value for the Rt/R ratio, and represents the minimum drag ogive for a given length. An ogive that’s perfectly tangent will have an Rt/R ratio of 1.0. Most ogives are in between an Rt/R of 1.0 and 0.5. The dimensioned drawings at the end of my Applied Ballistics book provide the bullets ogive radius in calibers, as well as the Rt/R ratio. In short, the Rt/R ratio is simply a measure of how secant an ogive is. 1.0 is not secant at all, 0.5 is as secant as it gets.
 Hybrid Bullet Design — Best of Both Worlds?
Bryan Litz has developed a number of modern “Hybrid” design bullets for Berger. The objective of Bryan’s design work has been to achieve a very low drag design that is also “not finicky”. Normal (non-hybrid) secant designs, such as the Berger 105gr VLD, deliver very impressive BC values, but the bullets can be sensitive to seating depth. Montana’s Tom Mousel has set world records with the Berger 105gr VLD in his 6mm Dasher, but he tells us “seating depth is critical to the best accuracy”. Tom says a mere .003″ seating depth change “makes a difference”. In an effort to produce more forgiving high-BC bullets, Bryan Litz developed the hybrid tangent/secant bullet shape.
Bryan Litz Explains Hybrid Design and Optimal Hybrid Seating Depths
Story sourced by Edlongrange.
June 19th, 2017
After 56 years Pat Farmer was reunited with the M1 Garand he used while serving his country.
By Ashley Brugnone, CMP Writer
Pat Farmer hadn’t felt the weight in his hands in 56 years. After five decades, the memories flooded back as his fingertips grazed the wood of the stock and gripped it tightly. It was a piece of his personal history, and the history of his country… and now, it’s a relic he’ll be able to keep for the rest of his life.
“I had never dreamed it would be in the CMP (Civilian Marksmanship Program) warehouse,” he said. “I had just hoped to possibly start a search beginning with the CMP.”
The 74-year-old from Jacksonville, NC, is a retired veteran who served 26 years in the armed forces. He was raised on a farm in Nebraska where he became familiar with guns at an early age. As a teen, he enlisted in the U.S. Marine Corps during his senior year in high school through a delay program. On August 30, 1960, he left for the Marine Corps Recruit Depot in San Diego, California, to attend boot camp — where he celebrated his 18th birthday.
Upon arrival he was issued M1 Garand #4305638. The firearm soon became a close companion as he spent countless hours with it on the “Grinder” — a Marine Corps term for a deck or parade ground used for drill and formations.
Reunited with M1 Garand after 56 Years
On May 8, 2017, Pat Farmer was reunited with M1 Garand #4305638 thanks to the CMP. Bringing it back to life, Pat began to fieldstrip the rifle. As he got to the trigger housing of the gun, he found something that he couldn’t believe – tape with his name and markings on it. It read, “Farmer 20/8L.” Pat believes it was his 500-yard “dope” – twenty clicks elevation, eight clicks left windage.
“Fifty-six years ago, we drilled and did the manual of arms with M1s as if they were matchsticks. It seems much heavier now!” Farmer added with a laugh.
Pat was eventually selected for aviation school after infantry training and shot on the rifle team while attached to a Reserve unit. He went on to shoot expert rifle at the Camp Mathews rifle range*. “It was some of the best and most rewarding years of my life,” he said.
Many years later, Pat one day went through an old locker box and found his custody receipt from Jan. 27, 1961, when he turned in his boot camp rifle before transferring to aviation school. Curiosity set in as he wondered whatever became of M1 Garand #4305638 – and the idea of finding it overcame him.
“I had purchased a few rifles from the old DCM and also CMP, so on a whim I decided to contact CMP to see if my old M1 had ever passed through their system,” he explained. Here’s the story of what happened and the years of waiting…
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