When shooting any match that requires moving back and forth between multiple target distances it is very handy to have your ballistics data, i.e. your “come-ups”, placed within easy view. That way you can instantly see your elevation for various target distances in seconds. This can really help a PRS/NRL competitor on timed stages. And having a convenient “Dope” display of elevation at various distances can also benefit varminters who are shooting critters. In our varmint hunters we targeted p-dogs from about 80 yards out to 500+.
PRC DOPE Roller QD Ballistic Data Turret
The PRC DOPE Roller QD Ballistic Data Turret provides a handy, low profile display of windage and elevation data. You can see your “dope” without breaking position from behind the rifle. Then simply rotate the knob to display data from various distances. The ballistic data is placed by wrapping a simple 1″ x 3″ adhesive address label around the outside surface of the DOPE Roller. This handy quick-detach roller retails for $64.95 from Precision Rifle Components.
MDT M-LOK Data Card Holder
The MDT M-LOK Data Card Holder has an adjustable neck allowing you to easily position your ballistics data for optimal viewing. Data entries are written on on a reusable card that attaches with Velcro. The Data Card Holder Kit comes with hardware to mount to any M-Lok rail. In addition the card holder fits directly to an MDT ACC chassis attachment point. This MDT kit includes: M-LOK Data Card Holder, Wet Erase Data Card, Wet Erase Marker, and installation hardware. NOTE: The Card Holder sticks out about 6.7″ when fully extended, but arm links can be removed to make the arm shorter. The unit folds flat for storage. This complete kit is $59.95 at Creedmoor Sports.
Warne Universal Data Card Holder
The Warne Universal Data Card Holder easily attaches to the scope tube, in left or right configurations, for a universal fit. Data is displayed in a convenient location to make quick and accurate target transitions, and the articulating arm allows for low profile storage while not in use. The Warne Universal Data Card Holder retails for $70.95 at Creedmoor Sports. Three ring sizes are offered: 30mm, 34mm, 35mm. A 50-pack of Warne Data Card label refills is currently $9.95 on sale.
Scope-Cover Mounted Ballistics Table
Another option is to place your ballistics card on the back of the front flip-up scope cover. This set-up is used by Forum member Greg C. (aka “Rem40X”).
With your ‘come-up’ table on the flip-up cover you can check your windage and elevation drops easily without having to move out of shooting position.
Greg tells us: “Placing my trajectory table on the front scope cover has worked well for me for a couple of years and thought I’d share. It’s in plain view and not under my armpit. And the table is far enough away that my aging eyes can read it easily. To apply, just use clear tape on the front objective cover.”
Cheap But Effective — Tape on the Stock with Ballistics Data
At the 2021 Nightforce ELR Steel Challenge, Applied Ballistics guru Bryan Litz wrote his come-ups on blue masking tape applied to his stock. He did this based on a tip from Chase Stroud. With the tape applied behind the action, the numbers are easily visible. This “cheap trick” does work apparently — Bryan won the match with a convincing victory over 220 other shooters. READ Match Report.
Cheap But NOT So Effective — Numbers on Hand
Many of us have scribbled some come-ups on the back of a hand or on our forearm using a marking pen. That can work if you only have a couple distances to deal with — say 100 and 300 yards. But if you want a more complete Come-up table, get one of the card-holders shown above. Writing numbers on the skin is generally not such a good idea….
Q: What’s more important — wind speed, or direction?
A: Obviously they both matter, but they do trade dominance based on direction. For example, a 10 mph wind between 2:30 and 3:30 is only changing its value from 9.7 to 10 to 9.7 mph (bracket of 0.3 mph). However a 10 mph wind between 11:30 and 12:30 is changing its cross wind component value from 2.6 mph left to zero to 2.6 mph right (bracket of 5.2 mph). There is the same 30° change in direction, but this results in a massively different bracket.
Point being, in this case, a direction change is far more critical if it’s near 6 or 12 o’clock. A small direction change when it’s close to 3 or 9 o’clock is negligible.
On the contrary, a change in wind SPEED when it’s near 3 or 9 affects your crosswind component directly. But for a near head or tail wind, a fluctuation in wind speed only causes a small fraction of a change to the crosswind component.
SUMMARY: If you’re in a near full-value wind, pay more attention to wind SPEED. If you’re closer to a head- or tail-wind, nailing the exact DIRECTION will be more important.
Get More Tips on Bryan Litz Ballistics Facebook Page
This post is from the new Bryan Litz Ballistics Facebook Page. FB users should check that page regularly for more tips from Bryan, American’s leading ballistics expert and founder of Applied Ballistics LLC.
Every Tuesday an interesting technical feature is posted on the Applied Ballistics Facebook Page. For today’s 4/23/24 “Tech Tuesday”, a fascinating video of a bullet in flight was posted. This Schlieren video illustrates a 6mm 109gr Berger LRHT bullet traveling at 3163 FPS. The stunning video reveals the bullet shockwave and the turbulent wake. Check it out:
About the Schlieren Imaging Process — What It Shows
Schlieren Imaging is a way of making airflow features visible. You can clearly see the compression (shock) wave at the front of the bullet. A compression wave is formed when the air has to move faster than the speed of sound to get out of the way, which is certainly the case for this bullet which is moving about 2.5 times the speed of sound (Mach 2.5). That shock wave is the ‘snap’ you hear when bullets fly past you if/when you’re downrange. Also, compressing the air into a shockwave takes energy, and that energy comes directly out of the forward velocity of your bullet and gets converted into heat and noise as the shock wave forms and dissipates. The turbulent wake at the base of the bullet shows where/how base drag applies. The third and smallest component of drag for a supersonic bullet is skin friction drag, which is a viscous boundary layer effect, and is the least visible in this image.
Above is a second Schlieren imaging video. This shows a 6mm 109gr Berger LRHT bullet at ~2800 fps as fired from a PRS rifle at the Applied Ballistics Lab. Bryan Litz notes: “You can clearly see the compression (shock) wave at the front of the bullet. A compression wave is formed when the air has to move faster than the speed of sound to get out of the way, which is certainly the case for this bullet which is moving about 2.5 times the speed of sound (Mach 2.5).”
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Initial radar testing shows an interesting stability trend for slugs vs. pellets: drag is minimized for pellets in slower-twist barrels, while drag of slugs is minimized for a faster twist. Also, consistency of drag/BC is best when drag is minimized (BC maximized).
Show below are test data for .300 caliber 44.5 grain Slug and .300 caliber 44.8 grain Pellet, both shot from an air rifle around 800 FPS. Experienced air rifle shooters told us to expect this so it’s nice to see the measurements supporting this trend!
So why is fast twist good for slugs while bad for pellets and vice versa? Air rifle pellets with a skirt are mostly drag-stabilized, not spin-stabilized. So, they don’t need much if any spin at all to fly point forward; the skirt catches the air like the fins of a rocket. As such, spinning the pellets faster only becomes a problem of dynamic stability. If I had any suggestion after looking at this data, it would be to try an even slower twist for pellets, perhaps a 1:60″ (one turn in 5 feet) or even 1:120″.
Slugs are spin-stabilized so it reasons that more spin suppresses yaw and maximizes BC, to a point. Based on these results, it appears the slug is reaching max stability/BC with the 1:22″ and the 1:18″ provides no further benefit. Again, these are just initial findings, we’re eager to explore further in the coming weeks! To view our recent Air Rifle projectile testing, with full 8-minute video, CLICK HERE.
“Shoot Like a Champion”. Bryan Litz, author of Applied Ballistics for Long-Range Shooting, says he often sees notes like this tucked in shooter’s gear (or taped to an ammo box) at matches. What “marksmanship mantras” do you use? Do you have a favorite quote that you keep in mind during competition?
On the Applied Ballistics Facebook Page, Bryan invited other shooters to post the motivating words (and little reminders) they use in competition. Here are some of the best responses:
“Shoot 10s and No One Can Catch You…” — James Crofts
“You Can’t Miss Fast Enough to Win.” — G. Smith
“Forget the last shot. Shoot what you see!” — P. Kelley
“Breathe, relax, you’ve got this, just don’t [mess] up.” — S. Wolf
“It ain’t over ’til the fat lady sings.” — J. McEwen
“Keep calm and shoot V-Bull.” — R. Fortier
“Be still and know that I am God[.]” (PS 46:10) — D.J. Meyer
“Work Hard, Stay Humble.” — J. Snyder
“Shoot with your mind.” — K. Skarphedinsson
“The flags are lying.” — R. Cumbus
“Relax and Breathe.” — T. Fox
“Zero Excuses.” — M. Johnson
“SLOW DOWN!” — T. Shelton
“Aim Small.” — K. Buster
“Don’t Forget the Ammo!” (Taped on Gun Case) — Anonymous
PARTING SHOT: It’s not really a mantra, but Rick Jensen said his favorite quote was by gunsmith Stick Starks: “Them boys drove a long ways to suck”. Rick adds: “I don’t want to be that guy”, i.e. the subject of that remark.
This report is from Bryan Litz and the ScienceofAccuracy.com website.
As long as there have been rifles, there has been a debate as to how much – if any – the rifle moves prior to the bullet exiting the bore. The first video below shows a Barrett MRAD chambered in .338 Lapua Magnum firing a 300gr Lapua Scenar bullet. Capturing projectiles at 100k+ frames per second allows us to visualize aspects of the firing sequence that are otherwise invisible to the human eye.
Click Video to see barrel with suppressor (on right) move with recoil before bullet exits.
What is clear from this video is that the rifle system is moving rearward while the bullet is traveling through barrel and subsequently through the suppressor. During the “in-bore” portion of bullet travel, any deviation of the muzzle orientation from the initial point of aim can cause a point of impact change. This is because the bullet will exit while the barrel is pointed somewhere different than when the shot was initially fired. Much of the shot’s point-of-aim orientation can be maintained through consistent marksmanship fundamentals and recoil management techniques. However, most shooters are not likely capable of managing it to less than 0.001″ for EVERY shot, especially given on lightweight magnum rifles.
Here’s another example with a 180gr bullet in a Rem 700 BDL .30-06 rifle. “Every time we watch a video like this it reminds us that guns like this, the majority of accuracy and precision come from the gun/sight/support system, not the ammo. When you consider that 0.005″ of muzzle deflection, (orthogonal to the bore) results in ~1.5 moa of dispersion (.75 in any direction) and you see this massive barrel movement prior to bullet exit, it’s clear that the vast majority of dispersion [for typical rifles] is coming from this movement”.
Precision rifle systems, such as benchrest, PRS, and F-Class rifles, tend to minimize the movement away from the bore axis prior to bullet exit to achieve the best possible precision. A common theme among the most precision systems is higher-weight rifles with lower-weight projectiles. This relates to basic physics: Newton’s Third of Motion “For every action, there is an equal and opposite reaction.” With all else held equal, if the rifle weighs more and the bullet weighs less, there is a lower magnitude of motion prior to the bullet leaving the barrel.
In our latest book, Modern Advancements in Long Range Shooting Volume III, Chapter 3 covers the Theory of Precision for Rifles which mathematically describes and estimates the precision potential of rifles based on rifle mass and kinetic energy of the bullet. The chapter includes all the live fire test data to support the theory and great discussion on the testing performed can be found on our podcast at the Science of Accuracy Academy website.
The Applied Ballistics Facebook Page features great, interesting new content posted multiple times each week. This resource features videos, test results, accuracy tips, and samples from Bryan Litz’s excellent books on ballistics and the three volume series on Modern Advancements in Long Range Shooting. Here are some highlights from Applied Ballistics’ Facebook posts from the past two weeks. Plus there’s a discount code, READ2024, that can save you 25% on Applied Ballistics books purchased in the month of March.
.22 LR Super Slow Motion Video — Watch the Bullet!
Watch .22 LR Rimfire Projectile Exiting Rifle Muzzle
This video, filmed with an ultra-high-speed camera, shows the milliseconds in time as a .22-caliber bullet travels the first 11 inches after leaving a .22 LR rifle barrel. Applied Ballistics states: “Notice that the bullet is fully obturated to the internal bore dimension — the step/rebate that exists on the unfired bullet where it meets the case gets expanded (obturated) and doesn’t exist on the fired bullet.”
How Important is Case Fill Ratio — You May Be Surprised
Conventional reloading practice is to select a powder that gives you a good case fill, meaning 90%-100% fill ratio for the cartridge and bullet you’re using. But why?
Some say that a higher fill ratio is good because it prevents the powder from settling differently in the case (which could lead to inconsistent ignition and greater MV SD). This explanation sounds good, and went unchallenged for a long time. However, Applied Ballistics has done some interesting testing that sheds new light on the density issue.
Modern Advancements in Long Range Shooting – Vol. 2 contains the results of Applied Ballistics tests of five different cartridge types — .223 Rem to .338 Lapua — loaded with different powders to produce fill ratios of 80%, 90%, and 100%. The testers wanted to see if 100% fill ratios actually gave better results (lower MV SDs) than the lower fill ratios.
Results of testing 3 different loads in 5 different cartridges — The highest MV SD was in fact measured in an 80% fill ratio load. However, the lowest MV SD was also measured for a different 80% load! Seems like the more we learn, the more questions we have. An informative Applied Ballistics podcast covers the Fill Ratio test. Visit Thescienceofaccuracy.com to access this and interesting podcasts.
EDITOR’s NOTE: There were multiple comments from Facebook readers stating that fill ratios 90% and above worked more consistently for them. And the reloading manuals warn against very low fill ratios.
Get 25% Off Applied Ballistics Books in March 2024
Applied Ballistics, through its Science of Accuracy webstore, is currently offering big savings on its popular books — considered to be the best print resources about rifle accuracy/ballistics ever published. This month you can save 25% on all six Applied Ballistics book titles by respected expert (and past national champion) Bryan Litz. Use Code READ2024 to get 25% of one or more of these books.
Get 25% OFF Applied Ballistics Books! Use code: READ2024 at checkout.
The team from Applied Ballistics will offer ballistics services at major matches in 2024. The team will have its advanced Doppler Radar unit which can provide ultra-precise custom ballistic profiles.
Applied Ballistics (AB) has announced the initial deployment schedule for the Applied Ballistics Mobile Laboratory during the 2024 shooting season. The Applied Ballistics Crew will be driving the Mobile Lab Truck and Trailer to a number of important shooting events in 2024. At these events you can get a Personal Drag Model (PDM) for your rifle/load based on Doppler Radar testing. NOTE: You must be actually competing at one of the listed events in order to participate and get a PDM. The first listed deployment will be at the NRL Hunter match in Montana on May 17, 2024. Here is the initial 2024 schedule:
May 17, 2024: Belt, Montana – NRL Hunter
June 7, 2024: Casper, Wyoming – Nightforce ELR
September 11-12, 2024: Grand Junction, Colorado – IPRF World Championships
The Applied Ballistics Mobile Lab trailer carries a vast array of equipment including computers, sensors, and advanced Doppler Radar equipment. The Doppler Radar is employed to create custom ballistic profiles (aka “Personal Drag Models”) for shooters at major matches.
Bryan Litz, founder of Applied Ballistics LLC, has a very informative Facebook page where he regularly posts useful ballistics info and shooting tips. We recommend that Facebook users check out the Bryan Litz Ballistics Facebook page. Here is one interesting example from that page. Bryan analyzes the Crosswind Weighting Factor (CWF). The Crosswind Weighting Factor (CWF) shows where a bullet’s trajectory is most susceptible to wind. By understanding CWF, shooters can better predict how wind affects bullet flight, especially at extreme ranges, when the projectile has gone transonic.
Crosswind Weighting Factor (CWF) graphs show where bullet trajectories are most susceptible to wind.
Where does the wind have the most effect?
At the shooter?
At the target?
Halfway?
Bryan Litz explains: “Out through the supersonic range, the CWF is maximum at the shooter. However as the trajectory extends into transonic, the max CWF gets pushed down range. That’s because the greatest segments of lag time in the bullets trajectory are at transonic where the drag coefficient is maximized around Mach 1.” [Editor: So if your bullet stays fully supersonic during its flight to your target, you can normally expect the CWF to be highest at your shooting station. But once the projectile drops into transonic speeds then the situation changes.]
Get More Tips on Bryan Litz Ballistics Facebook Page
This post is from the new Bryan Litz Ballistics Facebook page. You can bookmark that page at www.Facebook.com/BryanLitzBallitics. Facebook users will want to check that page regularly for other advice from Bryan, American’s leading Ballistics expert and founder of Applied Ballistics LLC.
Applied Ballistics also offers a noteworthy online training operation — The Science of Accuracy Academy. This will include podcasts, exclusive seminars, and access to the latest Applied Ballistics research.
Have you recently purchased a new scope? Then you should verify the actual click value of the turrets before you use the optic in competition (or on a long-range hunt). While a scope may have listed click values of 1/4-MOA, 1/8-MOA or 0.1 Mils, the reality may be slightly different. Many scopes have actual click values that are slightly higher or lower than the value claimed by the manufacturer. The small variance adds up when you click through a wide range of elevation.
In this video, Bryan Litz of Applied Ballistics shows how to verify your true click values using a “Tall Target Test”. The idea is to start at the bottom end of a vertical line, and then click up 30 MOA or so. Multiply the number of clicked MOA by 1.047 to get the claimed value in inches. For example, at 100 yards, 30 MOA is exactly 31.41 inches. Then measure the difference in your actual point of impact. If, for example, your point of impact is 33 inches, then you are getting more than the stated MOA with each click (assuming the target is positioned at exactly 100 yards).
How to Perform the Tall Target Test
The tall target test determines if your scope is giving you the proper amount of adjustment. For example, when you dial 30 MOA, are you really getting 30 MOA, or are you getting 28.5 or 31.2 MOA? The only way to be sure is to verify, don’t take it for granted! Knowing your scopes true click values insures that you can accurately apply a ballistic solution. In fact, many perceived inaccuracies of long range ballistics solutions are actually caused by the scopes not applying the intended adjustment. In order to verify your scope’s true movement and calculate a correction factor, follow the steps in the Tall Target Worksheet. This worksheet takes you thru the ‘calibration process’ including measuring true range to target and actual POI shift for a given scope adjustment.
NOTE: When doing this test, don’t go for the maximum possible elevation. Do NOT max out the elevation knob, running it to the top stop. Bryan Litz explains: “It’s good to avoid the extremes of adjustment when doing the tall target test. I don’t know how much different the clicks would be at the edges, but they are not the same.”
Tall Target Test For Milrad Scopes with B2B Target
This Precision Rifle Network video shows how to do a scope-tracking test using the pre-printed Sniper’s Hide Tall Target from Box to Bench Precision (B2B). With the primary line divisions in MILs, this printed target is perfect for Milliradian scopes. From bottom of the vertical line to the top there are 10 mils (36 inches) of travel. The markings are high contrast to make the testing easier.
In this video, there are some very helpful tips on setting up the target frame correctly and making sure the Tall Target is perfectly vertical. A plumb line can help. In this video the vertical tracking of a Burris XTR III 5.5-30x56mm scope is tested. Actual testing begins at 7:20 time-mark. The Precision Rifle Network has many other informative videos, with a new video released every week.
Should You Perform a WIDE Target Test Too?
What about testing your windage clicks the same way, with a WIDE target test? Bryan Litz says that’s not really necessary: “The wide target test isn’t as important for a couple reasons. First, you typically don’t dial nearly as much wind as you do elevation. Second, your dialed windage is a guess to begin with; a moving average that’s different for every shot. Whereas you stand to gain a lot by nailing vertical down to the click, the same is not true of windage. If there’s a 5% error in your scope’s windage tracking, you’d never know it.”
Verifying Scope Level With Tall Target Test
Bryan says: “While setting up your Tall Target Test, you should also verify that your scope level is mounted and aligned properly. This is critical to insuring that you’ll have a long range horizontal zero when you dial on a bunch of elevation for long range shots. This is a requirement for all kinds of long range shooting. Without a properly-mounted scope level (verified on a Tall Target), you really can’t guarantee your horizontal zero at long range.”
NOTE: For ‘known-distance’ competition, this is the only mandatory part of the tall target test, since slight variations in elevation click-values are not that important once you’re centered “on target” at a known distance.
Scope-Cover Mounted Ballistics Table
“Shoot Like a Champion”. Bryan Litz, author of 
Some say that a higher fill ratio is good because it prevents the powder from settling differently in the case (which could lead to inconsistent ignition and greater MV SD). This explanation sounds good, and went unchallenged for a long time. However, Applied Ballistics has done some interesting testing that sheds new light on the density issue.
Verifying Scope Level With Tall Target Test
