Jeffrey Block has created a great FREE software program, OnTarget, that measures shot groups quickly and precisely. All you need is a photo or scan of your target. The program allows you to set your target distance, and provides caliber-specific tools to precisely mark the center of each shot. Once you’ve marked each bullet hole, Jeff’s OnTarget program automatically calculates group center, maximum group spread (CTC), average distance to center, group width and height, and group offset from point of aim. The program will even measure multiple groups on the same target.
Video Tutorial Shows How OnTarget Software Works
Jeff created an excellent Animated Tutorial demonstrating OnTarget’s functions. It shows how to import a target image or scan, how to set target distance and scale, how to set bullet size, how to circle each bullet hole, and how to save the marked and measured target. VIEW OnTarget TUTORIAL.
After just a few minutes spent learning the program’s tool buttons, we were able to plot shot groups on a variety of targets with ease. Once you select the target distance and bullet diameter, figuring group size is a simple matter of centering a circle tool over each bullet hole. Then the program “connects the dots” and provides all the info you could want automatically.
The program worked with bullet holes as small as 17 caliber and as large as 50 caliber. It is very precise, but remember that if your target photo was taken at an angle, distorted perspective can cause slight errors in measurement. Therefore, for the ultimate precision, you want to start with a flat scan of the target.
OnTarget Compared to Measuring Manually
We found OnTarget to be especially useful for groups with widely dispersed bullet holes, or very small bullet holes, such as 17 caliber holes. We’ve found that it’s difficult to measure 17-cal group sizes with a standard caliper, because the tool itself obscures the tiny holes. With OnTarget, the program can zoom up your target view, making it much easier to plot the center of each shot. And with a widely dispersed group of shots, the program automatically finds the two most distant shots. You can’t mistakenly pick the wrong pair of shots to measure.
MEASURING REAL TARGETS — Actual Examples
Here are examples we created with OnTarget. The first photo shows a 17 Mach 2 target. These tiny 17-cal holes are notoriously hard to measure. With OnTarget, it’s a snap. You just load the target image into the program, zoom in with the controls, and then click on the center of the holes. The program automatically calculates group size, displaying measurements in both inches and minutes of angle (MOA)
Original Target (with ruler for scale)
Target Captured and Displayed in Program
Detail of Group, Enlarged by Program
10-shot Groups? — No Problem
Here’s another target, showing 6mm bullet holes at 600 yards. The first image shows the target image loaded into the program with the ten holes circled in red.
Target Displayed in Program
For this target we have used the Aiming Point option. The Aim Point was set at the center of the “X” and the program calculates average distance from the Aim Point. Very cool.
Detail of 10-Shot Group, Enlarged by Program
No Scanner Needed
The OnTarget program grabs target scans directly from a flatbed scanner using Microsoft’s Windows Image Acquisition system. But don’t worry if you don’t have a scanner. You can just take a digital photo of your target and OnTarget will import it quickly and easily. To set target scale, a simple tool allows you to mark a known length on the target (such as the diameter of the “X” Ring), and the program will then size the target accordingly. Is OnTarget precise and accurate? Here’s what Forum Member Steve W. says: “I used the extreme spread measurement of a group on one of my 600-yard match targets… as it was officially scored at the match. By clicking the +—+ icon, then clicked the cursor in the centers of the two extreme spread holes, I then entered that value in the reference window. After that it was simple because the bullet placement cursor’s circle was the same size as the black outline of the actual bullet holes on the picture of the target. OnTarget’s measurement came up within .006″ of the official 2.772 inch measurement of the group. That’s pretty darned close; well inside the human judgment of aligning the tips of a micrometer on the bullet holes.”
Bottom Line — Great Program — Download It Today
Jeffrey Block has done a great service for shooters by creating the FREE OnTarget program. It is easy to learn, it functions great, and it can save you time and effort measuring targets. It also lets you easily archive and compare multiple targets produced during load development or rifle testing. You can record ammo type, date, location, weather etc. in note fields accessed by “Group Info” and “Target Info” tabs.
Keep in mind that OnTarget was NOT created to replace existing methods for scoring competition targets. But for all other target measuring purposes it does a great job. Visit Jeff’s website, OnTargetShooting.com, view the tutorial, and check out OnTarget for yourselves.
To learn more about OnTarget, see more measuring samples, and read advanced Power-User Tips, visit our full OnTarget Product Review.
Share the post "Measure Your Groups Precisely with OnTarget Software"
What is Parallax?
Parallax is the apparent movement of the scope’s reticle (cross-hairs) in relation to the target as the shooter moves his eye across the exit pupil of the riflescope. This is caused by the target and the reticle being located in different focal planes.
Why is it Important?
The greater the distance to the target and magnification of the optic, the greater the parallax error becomes. Especially at longer distances, significant sighting error can result if parallax is not removed.
How to Remove Parallax
This Nightforce Tech Tip video quickly shows how to remove parallax on your riflescope.
While keeping the rifle still and looking through the riflescope, a slight nod of the head up and down will quickly determine if parallax is present. To remove parallax, start with the adjustment mechanism on infinity and rotate until the reticle remains stationary in relation to the target regardless of head movement. If parallax has been eliminated, the reticle will remain stationary in relation to the target regardless of eye placement behind the optic.
This Parallax Discussion first appeared in the Nightforce Newsletter. To get other helpful Tech Tips delivered to your mailbox, CLICK HERE to open the Nightforce Newsletter sign-up page.
Share the post "How to Correct for Parallax — Optics Tip from Nightforce"
For a prone shooter, particularly on dusty, dirty or sandy ground, muzzle blast is a major bummer. Muzzle blast can be very disturbing — not just for the trigger-puller but for persons on either side of the gun as well. Some muzzle brakes send a huge shockwave back towards the shooter, and others send blast towards the ground, kicking dirt and debris into the prone shooter’s face. If there was a way to illustrate those factors — shockwave and debris — that might help shooters select one brake design over another.
Cal Zant at PrecisionRifleBlog.com applied a unique blend of creativity and resourcefulness to try to answer that question for 20+ muzzle brakes. Using high-speed photography and household products, he captured the blast pattern of 20+ different brake designs for easy side-by-side comparison. Can you figure out how Cal managed to show muzzle brake blasts so clearly? His “hi-viz” solution, revealed in the article, is very clever. See the eye-opening results for 20+ brakes, with illustrative photos, by visiting the Precision Rifle Blog Muzzle Brake Ground Signature Test Page.
Share the post "Precision Rifle Blog Reveals Muzzle Brake Blast Patterns"
We’ve learned that many first-time visitors to AccurateShooter.com may come in via a link to the Daily Bulletin rather than through our home page. As a result, they may not be aware that there is a wealth of other content available to our readers. Our Shooters’ Forum, with nearly 33,000 registered members, is one of the best places on the web to discuss precision shooting and advanced reloading. We also offer FREE Forum Classifieds. On the editorial side, AccurateShooter.com offers hundreds of pages of content, with thousands of photos. Our Cartridge Guides are definitive one-stop resources for popular match calibers, while our Guns of the Week articles spotlight outstanding custom rifles, most with competition pedigrees. In addition, we offer videos, gear reviews, book reviews, gunsmithing tips, and even FREE downloadable targets.
If you’re a new visitor to AccurateShooter.com, you should check out all that we have to offer. There are hundreds of informative articles to read … and they’re all FREE.
A while back, RifleShooter online magazine published a list of the purported Ten Best Bolt-Action Rifles of All Time. Ten classic rifle designs (including the Remington 700 and Winchester Model 70) were featured with a paragraph or two explaining their notable features.
“Best” Lists Stir Controversy…
These Top 10 lists are always controversial. While most readers might approve of half the entries, there are always some items on the Top 10 list that some readers would challenge. Here is RifleShooter’s Top 10 list. What do you think? Are there some other bolt-actions that are more deserving?
1. Springfield M1903
2. Mauser 98
3. Winchester Model 70
4. Remington Model 700
5. Weatherby V
6. Sako L61/AV
7. Savage Model 110
8. Ruger M77
9. Tikka T3
Share the post "Are These Really the TEN BEST Bolt-Action Rifles?"
Here’s something truly innovative — a 3D-printed metal rimfire receiver!
Forum member Marcos G. (aka MFP_BOP) has designed and created his own rimfire action. But it’s not machined or forged. This new action was created with a 3D sintered metal printer. A 3D modeler by profession, Marcos has the requisite skill set and access to a very high-tech (and expensive) metal printer. As printed, the actual receiver is shown below. It has just been sent out to be age-hardened to 40 HRC, after which final finish work (e.g. cleaning up tenon threads) will be done. To learn more about this 3D-printing project, read this FORUM Thread.
When most of us think of 3D printing, we think of small plastic parts — nothing as strong as steel. But there are 3D printers that employ sintered metal to build complex metal components. Marcus says the receiver he’s created should have “stated yield and tensile strength similar to investment casting.” The material used for the action is 15-5 PH® Stainless Steel (in sintered form).
The action was designed to use a PT&G 40X rimfire bolt. Marcos notes that “There is an extraction cam inside of the action, something that would be very hard or impossible to do by regular machining and/or EDM.”
Born in Brazil, Marcos now lives in New Zealand. He tell us that: “New Zealand is a very gun-friendly country. I just need my A-CAT license to make [a receiver.]” So there are no special legal restrictions (as might apply in the USA). The printer is EOS270 laser metal sintering machine. Marcos says: “The current price for one of those machines is in five figures, but I am 99.99% sure that in 5-7 years this technology will be readily available to anyone.”
As designed, the receiver was 1.4″ in diameter. Marcos reports it came out of the printer at 1.403″. The designed boltway is .690″ and it came out .687″. Marcos notes: “I haven’t noticed any warping. The threads are rough, really! Interior and exterior finishes are really good though, probably because of the way it’s been printed: upside down (must have gone through tumbling afterwards). I will have to run some taps and single-point-cut the tenon threads to clean them up.”
Marcos says the actual printing process took a lot of time: “I should have asked how long it took to be printed!” But consider this, the 7″-long receiver is created in layers only 20 microns thick, so you can understand why the process took so long.
Reasons to Print a Rimfire Receiver
Marcos 3D-printed his own action basically to save money: “Some may be asking why I printed this receiver. Here’s a little history… I tried different ways to bring a Stiller 2500X action into New Zealand. The final price to my door was NZ $3000.00 (about $2195.00 USD). Designing and making one would be way cheaper, but I felt nobody here could machine the internal abutments with precision. Also printing was still a little cheaper and printing offered the chance to put in it all details I wanted — such as M4 threads, internal cam, and fillets.”
Share the post "3D Metal Printed Rimfire Receiver from New Zealand"
This summer, our friend Dennis Santiago made his first-ever pilgrimage to Camp Perry, Ohio to compete in the National Matches. He recounts his experience in a fascinating, informative, and often humorous story on his Dennis Talks Guns Blog. When you have a few moments to spare, you should definitely read Santiago’s account of his First Time at Camp Perry. This is much, much more than a match report. Dennis gives insights into the human side of the experience — and the little things that make Camp Perry so special. CLICK HERE to Read Full Camp Perry Story.
Dennis competed in a number of events during his two-week stay. Shooting “classic” service rifle and his new scoped, “modern AR” service rifle Dennis competed solo (in Presidents 100 and NTI matches among others) and also as a member of the California Adult Team in the 4-man NTT match.
Santiago’s First Time at Camp Perry report is a “must-read” for anyone contemplating a Camp Perry visit. Here are some highlights — but honestly folks, do read the entire story — it’s well worth it.
First Time at Camp Perry, by Dennis Santiago
Perry Ain’t Like Home
Iron Sights and “Perry-Vision”
This range is kicking me hard. I tell people about how hard I was pushing my eye into my aperture. They smile that “welcome to Camp Perry” smile again. They ask what sights I’m shooting on my A2 and I tell them I’ve got an 0.050″ front and 0.038″ rear to maximize depth of field. They smile more broadly and tell me my problem is that I’m from the Western provinces where the sun is bright and the ground is devoid of flora. Lots of light. It’s green here and we have clouds I’m told. Not nearly the same ambient lighting. You have the wrong sights my son. Where the green grass grows you want a big fat 0.072″ front the size of an aircraft carrier deck and a huge 0.046″ hole in the morning and maybe close it down to an 0.042″ rear aperture later if the sun comes out. But that desert glare sight system of yours will lose you about 5-8 points in these parts. Well there you go. Learn something every day.
Baptism at Camp Perry
One’s first visit to Camp Perry is a series of baptismal rites. I shall now enumerate them…
Walk the Base. Do not drive around. Get used to walking. Walk from your hut to everything. Walk to the administration buildings. Walk to the ranges. Walk to commercial row. Walk to the CMP North Store. Walk to the CMP or Army trailer to have the triggers of your rifles(s) weighed. Walk. This is your primary mode of transportation while on base for the next couple of weeks.
Go Shopping. It’s called Commercial Row. It is the best shopping mall for competitive shooters ever. The sale prices here are Black Friday quality. You stock up on supplies. You can buy elusive powders in quantity with the same lot number. Same with bullets and primers. Everything you need to keep making your pet loads. Oddly, not cases. This is a service rifle tournament. Pretty much everyone is using LC or WCC cases. I stocked up. Then I began politely watching my expected cubic feet and gross weight capacity for the drive home as other people asked if I could take stuff back for them instead of shipping their loot.
Learn about the Perils of Perry. One, evacuate the range. It rains at Camp Perry. Sometimes that rain comes with lightning. When that happens range controls issues an evacuation order. Depending on where you are and how much time you have, you either grab your stuff and make for a sheltered structure or leave your stuff under whatever rain cover you have and leave it there until the storm cell passes. This happened on squadded practice day. There was no squadded practice. There was learning to make a better rain cover for the next two weeks because it’d probably happened again. I was particularly proud of my final design which involved a very large tarp and many bungee cords. Modern art to be sure. I received many compliments.
Peril Two — Cease fire, boat in the impact area. One has not truly been to Camp Perry until your shooting string is put on hold while range control sends someone out to tell an errant yacht or jet ski that it’s not a good idea to go into that area with all the buoys with the signs on them that say, Danger. Live Fire. Keep Out.
I brought two rifles with me to Camp Perry. The first was my iron sights-configured AR-15. Being my very first trip to the Nationals, I wanted to check off a bucket list item to shoot irons at a National Match. The gun has a Geiselle trigger and an upper I assembled from White Oak Armament parts. The barrel is a Krieger that had 3,800 rounds arriving at Perry. The sights are pinned 1/4×1/4s. I run Sierra 77gr SMKs short line and 80gr SMKs seated .015″ off the lands Long Line with it.
The other rifle I brought was for NRA week. It’s a 2016 Rule Service Rifle, Optic. It has a collapsible UBR stock and a Geiselle Mk VII quad rail. The barrel is an older DPMS .223 that was cryo-treated back in the day. Round count on arrival at Nationals was around 1,800. Same ammunition combination [as the iron sights rifle]. The chamber on this barrel has a shorter throat so I brought a Lee Hand Press with an RCBS competition seater die to set the 80gr SMKs back to proper jump for NRA week. The sighting system for this gun was one of the very new Nightforce 4.5X Competition SR’s with the CMP R223 reticle. Parallax is set to 200 yards. It’s mounted using Nightforce’s superbly engineered AR-15 service rifle Unimount.
Members of the State of California Teams at Camp Perry. Dennis is front row left.
Coaching — When It All Comes Together, at Last
I coached one of the California teams in the NTIT Rattle Battle match. This was the day I finally began to be comfortable at Camp Perry. Walking up and down the field, first as a verifier and then as a coach, I felt back in the game. At team matches you get to confer with your teammates comparing wind calls and observing the effects of their calls as the shooting members of their squads send rounds downrange. You watch the traces of bullets arcing in the air going left or right of the bull’s center depending whether or not the call was right. This process was cathartic. I began to remember that I really can read a range once I get the hang of it.
Share the post "Dennis Does Perry — Two Weeks at the National Matches"
Here is an interesting project by one of our Forum members. Martin C. (aka “Killick”) modified an Anschutz 1411 Match 54 rimfire prone stock to become a comfortable, great-tracking F-Class Open Division Stock. No Killick didn’t sacrifice a perfectly good rimfire rifle for this project — he bought the Anschutz stock by itself on eBay, then transformed it…
Killick explains: “This project started about seven years ago. I bought the Anschutz prone stock on eBay and whittled it a bit into a Palma rifle with a Barnard action and block and a Doan Trevor cheek piece and scope rail. Then about two years ago I decided to re-task the stock/action assembly into an F-Open rig. With more whittling, gluing, sanding, body fillering, sanding, filling, sanding, more sanding…and sanding, forming, priming, sanding, painting, waiting, painting, painting…painting and before you know it, Bob’s your uncle.”
Here is the eBay-sourced Anschutz 1411 stock, with new high-gloss blue finish, as initially modified for use in Killick’s centerfire Palma rifle. Looks nice!
Next step was the addition of a 3″-wide wood fore-end for F-Open duties with front rest:
Almost done here… just needs priming and final painting:
Here is Killick’s completed F-Open rifle with its much-modified Anschutz stock now finished in fire-engine red lacquer. This image shows the detail of the grip and customized cheekpiece.
Readers who have just recently discovered the Daily Bulletin may not realize that AccurateShooter.com has hundreds of reference articles in our archives. These authoritative articles are divided into mutiple categories, so you can easily view stories by topic (such as competition, tactical, rimfire, optics, shooting skills etc.). One of the most popular categories is our Technical Articles Collection. On a handy index page (with thumbnails for every story), you’ll find over 120 articles covering technical and gunsmithing topics. These articles can help you with major projects (such as stock painting), and they can also help you build more accurate ammo. Here are five popular selections from our Technical Articles archive.
Most shooters realize that significant changes in temperature will alter how powders perform. That’s why you want to keep your loaded ammo out of the hot sun, and keep rounds out of a hot chamber until you’re ready to fire. But there are other factors to be considered — HUMIDITY for one. This article explains why and how humidity can affect powder burn rates and performance.
We’ve all heard the old adage: “Keep your powder dry”. Well, tests by Norma have demonstrated that even normal environmental differences in humidity can affect the way powders burn, at least over the long term. In the Norma Reloading Manual, Sven-Eric Johansson, head of ballistics at Nexplo/Bofors, presents a very important discussion of water vapor absorption by powder. Johansson demonstrates that the same powder will burn at different rates depending on water content.
Powders Leave the Factory with 0.5 to 1.0% Water Content
Johansson explains that, as manufactured, most powders contain 0.5 to 1% of water by weight. (The relative humidity is “equilibrated” at 40-50% during the manufacturing process to maintain this 0.5-1% moisture content). Importantly, Johansson notes that powder exposed to moist air for a long time will absorb water, causing it to burn at a slower rate. On the other hand, long-term storage in a very dry environment reduces powder moisture content, so the powder burns at a faster rate. In addition, Johansson found that single-base powders are MORE sensitive to relative humidity than are double-base powders (which contain nitroglycerine).
Tests Show Burn Rates Vary with Water Content
In his review of the Norma Manual, Fred Barker notes: “Johansson gives twelve (eye-opening) plots of the velocities and pressures obtained on firing several popular cartridges with dehydrated, normal and hydrated Norma powders (from #200 to MRP). He also gives results on loaded .30-06 and .38 Special cartridges stored for 663 to 683 days in relative humidities of 20% and 86%. So Johansson’s advice is to keep powders tightly capped in their factory containers, and to minimize their exposure to dry or humid air.”
Confirming Johansson’s findings that storage conditions can alter burn rates, Barker observes: “I have about 10 pounds of WWII 4831 powder that has been stored in dry (about 20% RH) Colorado air for more than 60 years. It now burns about like IMR 3031.”
What does this teach us? First, all powders start out with a small, but chemically important, amount of water content. Second, a powder’s water content can change over time, depending on where and how the powder is stored. Third, the water content of your powder DOES make a difference in how it burns, particularly for single-base powders. For example, over a period of time, a powder used (and then recapped) in the hot, dry Southwest will probably behave differently than the same powder used in the humid Southeast.
Reloaders are advised to keep these things in mind. If you want to maintain your powders’ “as manufactured” burn rate, it is wise to head Johannson’s recommendation to keep your powders tightly capped when you’re not actually dispensing charges and avoid exposing your powder to very dry or very humid conditions. The Norma Reloading Manual is available from Amazon.com.
Real-World Example — “Dry” H4831sc Runs Hotter
Robert Whitley agrees that the burn rate of the powder varies with the humidity it absorbs. Robert writes: “I had an 8-lb. jug of H4831SC I kept in my detached garage (it can be humid there). 43.5-44.0 gr of this was superbly accurate with the 115 Bergers out of my 6mm Super X. I got tired of bringing it in and out of the garage to my house for reloading so I brought and kept the jug in my reloading room (a dehumidified room in my house) and after a few weeks I loaded up 43.5 gr, went to a match and it shot awful. I could not figure out what was going on until I put that load back over the chronograph and figured out it was going a good bit faster than before and the load was out of the “sweet spot” (42.5 – 43.0 gr was the max I could load and keep it accurate when it was stored in less humid air). I put the jug back in the garage for a few weeks and I now am back to loading 43.5 – 44.0 gr and it shoots great again. I have seen this with other powders too.”
If you have two jugs of the same powder, one kept in a room in your house and one somewhere else where it is drier or more humid, don’t expect the two jugs of the same lot of powder to chrono the same with the same charge weights unless and until they are both stored long enough in the same place to equalize again.
Share the post "Humidity and Powder Burn Rates — What You Need to Konw"
John Whidden of Whidden Gunworks used the .243 Winchester cartridge to win the 2016 NRA Long Range Championship, his fourth LR title at Camp Perry. John selected the .243 Win because it offers excellent ballistics with manageable recoil. John says that, at least for a sling shooter, the .243 Win is hard to beat at long range. Yes, John says, you can get somewhat better ballistics with a .284 Win or .300 WSM, but you’ll pay a heavy price in increased recoil.
.243 Winchester — The Forgotten 6mm Cartridge for Long Range
by John Whidden, 2016 National Long Range Champion
My experience with the .243 cartridge for use as a Long Range High Power cartridge dates back about 10 years or so. After building a .300 WSM, I realized that the recoil was hurting the quality of my shots. The WSM shot great, but I couldn’t always execute good shots when shooting it. From here I built a 6.5-284, and it shot well. I also had a very accurate 6mmBR at the time, and my logic in going to the .243 Win was to get wind performance equal to the 6.5-284 with recoil similar to the 6mmBR. The experiment has worked out well indeed!
Championship-Winning Load: Berger Bullets, Lapua Brass, and Vihtavuori N160
For a load, currently I’m shooting Lapua brass, PMC primers (Russian, similar to Wolf), VihtaVuori N160 single-base powder, and Berger 105 grain Hybrid bullets. I switched to the Hybrid bullets fairly recently at the beginning of the 2015 season. Previously I shot the 105gr Berger hunting VLDs, and in testing I found that the Hybrids were just as accurate without having to seat the bullet into the lands. The velocity of this combination when shot through the excellent Bartlein 5R barrels (32” length) is around 3275 FPS.
For my match ammo, I seat the Berger 105 Hybrids well off the lands — my bullets are “jumping” from .035″-.060″. I only use one seating depth for ammunition for multiple guns (I know some benchrest shooters will stop reading right here!) and the bullets jump further in the worn barrels than in the fresh barrels. The bullets are pointed up in our Bullet Pointing Die System and are moly-coated. The moly (molybdenum disulfide) does extend the cleaning interval a little bit, probably 20% or so. The Lapua .243 Win brass is all neck-turned to .0125″ thickness.
Whidden’s .243 Win Ammo is Loaded on a Dillon
My loading process is different than many people expect. I load my ammo on a Dillon 650 progressive press using our own Whidden Gunworks dies. However powder charges are individually weighed with a stand-alone automated scale/trickler system from AutoTrickler.com (see below). Employing a high-end force restoration scale, this micro-processor controlled system offers single-kernel precision. The weighed charges are then dropped into the cases with a funnel mounted to the Dillon head.
The Lapua .243 Win brass is full-length sized every time, and I run one of our custom-sized expanders in my sizer die. The expander measures .243″ which yields the desired .001″ neck tension. In my experience, the best way to get consistent neck tension is to run an expander in the case neck at some point. When sizing the case neck by a minimal amount such as is the case here, I don’t find any negative points in using an expander in the sizer die.
In my experience, the keys to accurate long range ammo are top quality bullets and the most consistent neck tension you can produce. From these starting points, the use of quality components and accurate powder measurement will finish out the magic.
Great Ballistics with 6mm 105s at 3275 FPS
Running at an impressive 3275 FPS, Berger 6mm 105 grain Hybrids deliver ballistics that are hard to beat, according to John Whidden:
“My .243 Win shoots inside a 6.5-284 with 142-grainers. Nothing out there is really ahead of [the .243], in 1000-yard ballistics unless you get into the short magnums or .284s and those carry a very significant recoil penalty. In the past I did shoot the 6.5-284. I went to the .243 Win because it had similar ballistics but had much less recoil. It doesn’t beat me up as much and is not as fatiguing.
With the .243 Win, there’s no tensing-up, no anticipating. With the reduced recoil (compared to a 7mm or big .308), I can break and shoot very good quality shots. I find I just shoot better shots with the .243 than I ever did with the 6.5-284.”
Share the post "Whidden on Winning at Long Range: Part 2 — The Cartridge"
On some internet shooting forums, self-declared “experts” advise new rifle shooters to stick to low-end factory rifles. These “experts” (many of whom don’t own a single really accurate rifle), claim that it will take years for a new shooter to learn how to shoot a rifle accurately. So, the argument goes, the accuracy offered by a precision-chambered rifle, with a custom barrel, is “wasted” on a new shooter.
We disagree with that viewpoint, at least when it comes to rifles shot from a rest. We’ve seen relatively new shooters, with help from a skilled mentor, do remarkably well with precision rifles right from the start. With a good bench gun, many new shooters can shoot well under 1 MOA on the first day. Certainly it takes time for a complete novice to learn how to handle the gun and to work the trigger smoothly. However, this editor has personally seen some inexperienced shooters try their hand at benchrest shooting, and within few month they are doing very well indeed at club shoots.
Accurate Rifles Reward Progress As Novices Build Skills
For bench shooting, we think a highly accurate rifle is a much better training device for a new shooter than a typical, cheap factory sporter. With a gun capable of 1.5-2.0 MOA at best, you can never really determine if a “flyer” is you or the gun. Conversely, when a novice shoots a gun that can put 5 shots through one ragged hole, if a shot goes way high or low, the shooter knows his aim, trigger control, or gun-handling is to blame. He (or she) can then correct the problem. And when the shooter does everything right, he or she will see a nice tight group on the target. The accurate rifle provides more meaningful feedback and it rewards progress. That helps the novice become a better shooter in a shorter period of time.
A while back, Forum Member Preacher and his “bunny hugger” niece from California proved this point. The young lady, with almost no shooting experience, took Preacher’s 6-6.5×47 and shot a sub-quarter-MOA, 3-shot group at 350 yards. Don’t tell her she needs to stick to a cheap factory rifle. Preacher reports: “My niece flew in from the west coast and came up to visit. When she saw a few of my full-blown varmint rifles, she wanted to shoot one. She did a super job even if she IS a ‘bunny hugger’. She pulled the 1.5 ounce Jewell on a few fired cases to check out the trigger pull and then got in behind the gun and put three shots into a 350-yard target with a one-inch circle.” We measured her group at 0.822″ (0.224 MOA). Don’t tell Preacher that accuracy is “wasted” on novices. He joked: “I sure don’t want her shooting at me ….”
Rifle Features BAT Action, Krieger Barrel, and Russo Laminated Stock:
For those who are interested, Preacher’s rifle features a BAT 3-lug action, 30″ Krieger 7.5-twist heavy contour barrel, and Russo stock (with clear coat by Preacher). Chambered in 6-6.5×47 Lapua, this gun “shoots the 108gr Bergers very well” according to Preacher. Yep, we agree with that — even when a novice “bunny-hugger” does the trigger-pulling.
Share the post "Novice Shooters Deserve Accurate Rifles Too…"
With suicide accounting for nearly two-thirds of all firearm fatalities annually, the topic of suicide prevention deserves our attention. In recent years NSSF has worked with the Veterans Administration, the State of Utah, and mental health agencies to help educate gun owners and the public on how to keep firearms safely out of reach of those who, during a period of despair, decide to do themselves harm.
According to Centers for Disease Control and Prevention (CDC) Data:
1. Nearly half of all suicides were by firearm in 2014.
2. Suicide accounted for almost two-thirds of gun deaths in 2014.
3. 90 percent of suicide attempts with a firearm are fatal.
The NSSF has committed to broaden its efforts, in partnership with the American Foundation for Suicide Prevention (AFSP). Recently, NSSF and AFSP announced a partnership to embark on a first-of-its-kind national plan to build and implement public education resources for firearms retailers, shooting ranges, and the firearms-owning community about suicide prevention and firearms.
Experts say that suicide results from the culmination of several health and life factors, with the decision to act often being made in minutes. Keeping firearms securely stored puts space between the period of risk and the means to act, and sometimes that … can help save a life.
AFSP has commenced a four-state pilot program that will involve firearms retailers and shooting ranges. This pilot program employs AFSP/NSSF jointly-developed strategies and resources to inform firearm owners about warning signs, prevention resources and secure firearms storage options. The NSSF also supports AFSP’s Project 2025, an initiative to reduce the annual suicide rate 20 percent by 2025. You will be hearing more about AFSP and NSSF efforts in this area.
Share the post "NSSF Expands Suicide Prevention Programs"
In this .308 Win test, 70° F ammo shot 96 FPS slower than ammo heated to 130.5° F. And the 130.5° ammo was 145 fps faster than ammo right out of the freezer (at 25.5° F). That’s a huge difference…
EDITOR’s NOTE: The Sierra tester does not reveal the brand of powder tested here. Some powders are much more temp sensitive than others. Accordingly, you cannot extrapolate test results from one propellant to another. Nonetheless, it is interesting to see the actual recorded velocity shift with ammo temperature variations in a .308 Win.
Written by Sierra Chief Ballistician Tommy Todd This story originally appeared in theSierra Bullets Blog
A few weeks ago I was attending the Missouri State F-Class Match. This was a two-day event during the summer and temperatures were hot one day and hotter the next. I shot next to a gentleman who was relatively new to the sport. He was shooting a basically factory rifle and was enjoying himself with the exception that his scores were not as good as he hoped they would be and he was experiencing pressure issues with his ammunition. I noticed that he was having to force the bolt open on a couple of rounds. During a break, I visited with him and offered a couple of suggestions which helped his situation somewhat and he was able to finish the match without major issues.
He was shooting factory ammunition, which is normally loaded to upper levels of allowable pressures. While this ammunition showed no problems during “normal” testing, it was definitely showing issues during a 20-round string of fire in the temperatures we were competing in. My first suggestion was that he keep his ammunition out of the direct sun and shade it as much as possible. My second suggestion was to not close the bolt on a cartridge until he was ready to fire. He had his ammo in the direct sunlight and was chambering a round while waiting on the target to be pulled and scored which can take from a few seconds to almost a minute sometimes.
This time frame allowed the bullet and powder to absorb chamber [heat] and build pressure/velocity above normal conditions. Making my recommended changes lowered the pressures enough for the rifle and cartridge to function normally.
Testing Effects of Ammunition Temperature on Velocity and POI
After thinking about this situation, I decided to perform a test in the Sierra Bullets underground range to see what temperature changes will do to a rifle/cartridge combination. I acquired thirty consecutive .30 caliber 175 grain MatchKing bullets #2275 right off one of our bullet assembly presses and loaded them into .308 Winchester ammunition. I utilized an unnamed powder manufacturer’s product that is appropriate for the .308 Winchester cartridge. This load is not at the maximum for this cartridge, but it gives consistent velocities and accuracy for testing.
I took ten of the cartridges and placed them in a freezer to condition.
I set ten of them on my loading bench, and since it was cool and cloudy the day I performed this test I utilized a floodlight and stand to simulate ammunition being heated in the sun.
I kept track of the temperatures of the three ammunition samples with a non-contact laser thermometer.
The rifle was fired at room temperature (70 degrees) with all three sets of ammunition. I fired this test at 200 yards out of a return-to-battery machine rest. The aiming point was a leveled line drawn on a sheet of paper. I fired one group with the scope aimed at the line and then moved the aiming point across the paper from left to right for the subsequent groups.
NOTE that the velocity increased as the temperature of the ammunition did.
The ammunition from the freezer shot at 2451 fps.
The room temperature ammunition shot at 2500 fps.
The heated ammunition shot at 2596 fps.
The tune window of the particular rifle is fairly wide as is shown by the accuracy of the three pressure/velocity levels and good accuracy was achieved across the board. However, notice the point of impact shift with the third group? There is enough shift at 200 yards to cause a miss if you were shooting a target or animal at longer ranges. While the pressure and velocities changed this load was far enough from maximum that perceived over pressure issues such as flattened primer, ejector marks on the case head, or sticky extraction did not appear. If you load to maximum and then subject your ammunition to this test your results will probably be magnified in comparison.
This test showed that pressures, velocities, and point-of-impact can be affected by temperatures of your ammunition at the time of firing. It’s really not a bad idea to test in the conditions that you plan on utilizing the ammo/firearm in if at all possible. It wouldn’t be a bad idea to also test to see what condition changes do to your particular gun and ammunition combination so that you can make allowances as needed. Any personal testing along these lines should be done with caution as some powder and cartridge combination could become unsafe with relatively small changes in conditions.
Share the post "Sierra Test Reveals How Velocity Varies with Ammo Temperature"
Jim Laughland (far left) with Alice Bull, the first Distinguished female (third from left).
Article based on story by Ashley Brugnone, CMP Writer
Jim Laughland, age 77, was the presenter of the Alice Bull Trophy during the 2016 National Trophy Rifle Matches at Camp Perry. To Jim, the Alice Bull Trophy is something very special … it rekindles memories of a cherished friend and mentor, and his many decades at Camp Perry. “I just thought it’d be nice to have the chance to present it because I don’t know if I’m coming back again,” he said. “Otherwise, you might have someone presenting who never knew [Alice Bull] or loved her like I did.”
The first female to earn the Distinguished Rifleman Badge, Alice Bull was an extraordinary individual. A true pioneer, she was the women’s rifle team captain at the University of Washington. Before WWII, Bull competed at the National Matches from 1935 – 1937. In 1949, Alice became the first woman elected to the NRA’s Board of Directors. She went on to become the first female to earn the Army’s Distinguished Rifleman Badge in 1961.
The Alice Bull Trophy, awarded to the highest aggregate civilian competitor during the National Rifle Matches, was first presented in 1991 by the Washington State Rifle and Pistol Association to commemorate this legendary woman and competitive shooter. The trophy features a bronze figure of Alice on top, with two rifles below, one the actual M1 Garand with which Alice earned her Distinguished Rifleman Badge.
Jim first met Alice Bull when he was a young member of the Seattle Rifle & Pistol Club. He had been friends with her son, Lee, and Jim shot with Alice in an indoor smallbore league. She helped him develop his marksmanship skills, including perfecting the cross-ankle sitting position that he still uses. Now, the woman he knew is immortalized in a perpetual trophy.
“I think it’s wonderful. And, incredible that she was a woman,” he said. “I treated her like my mother. She was very kind — a brilliant, wonderful person.”
Sixty Years of Marksmanship Starting at Camp Perry
During his 60 years of marksmanship experience, Jim has traveled all around the country and has competed with many of the most recognized individuals in the world of shooting. And, it all began at Camp Perry. “When I come to Camp Perry, there are a lot of ghosts I know, walking around,” he said.
Jim’s first visited Camp Perry in 1955, when he was just 17 years old. Jim even skipped his first week of high school to attend the National Matches. Jim started out unclassified, but left an Expert Marksman. During his early career, he shot with the Washington State National Guard and the New York National Guard. In 1962, he moved to Baltimore and joined the Maryland State Team which went on to win the Hilton Trophy for the High National Guard Team in the National Trophy Team Match. Later, he earned his Distinguished Rifleman Badge in 1964.
Head to Head with Carlos Hathcock
In August 1965, Laughland shot in one of his most memorable Camp Perry matches — going shoulder-to-shoulder with Carlos Hathcock, famed marksman and Marine Corps sniper in Vietnam. Hathcock won the Wimbledon Cup Match by a single point. “He’s the one who made me famous”, Jim said with a smile.
Jim also notably shot with two-time Olympic gold medalist and Director of Civilian Marksmanship Emeritus, Gary Anderson, in the 1960s while both were members of the All National Guard Team. Shown below are Anderson and Laughland at Camp Perry.
Another memorable match for Jim came in 1977, when he joined the All National Guard National Rifle Team and traveled to Camp Perry with them as only an alternate – or so he thought. On that day, with blustery 30 to 40 mph winds, Jim remembers remarking to his friend, “I’m glad I don’t have to shoot in this wind today!” Soon after, the colonel came up to Jim and told him he’d be shooting. At that point in his career, it had been 10 years since he had shot with the All Guard team. “I looked at my friend, thinking, ‘Should I cheer or cry?’” he joked.
At the end of the match, he and his friend were the high shooters on the team and won the National Trophy Team Match for the National Guard for the first time in 65 years.
“When I think about it, I get teary. It was such an honor,” he said. “I think it was one of the highlights of my shooting. It was like going into the World Series, in the 7th game with bases loaded, 3 runs down with a 3-2 count and hitting a Grand Slam.”
High Master and Three Grand Senior Service Rifle Championships
In 1979, the NRA introduced the High Master Classification, and Laughland became the first on the All Guard team to earn the title. Most recently, Jim won the Grand Senior Service Rifle Championships in 2008, 2009 and 2014 at Camp Perry, saying the desire to win is what keeps him shooting.
“When I found out they had the ‘old folks’ award, I switched to Service Rifle,” he said. “And I figured I’d never win it again, because these younger guys are coming in — you know, who are only 70 or 75. But when I looked and saw my name on the bulletin in 2014, I started to cry.”
Laughland Leaves a Legacy
In 2015, Jim was diagnosed with Parkinson’s disease, which has left him with some ailments that make it difficult to compete at his top level. But, with the reputation that precedes him, he has many friends at the National Matches, both old and new, that are always eager to welcome him back. “I have a hard time coming to Camp Perry and walking around without someone stopping me and asking me to take a picture with them,” he said. “I get choked up.”
“I’d like to leave a legacy,” he said. “When I don’t make it to Camp Perry anymore, it’s the people I’ll miss the most. It’s been my life….”
The Civilian Marksmanship Program is a federally chartered 501 (c) (3) non-profit corporation. It is dedicated to firearm safety and marksmanship training and to the promotion of marksmanship competition for citizens of the United States. For more information about the CMP and its programs, log onto www.TheCMP.org.
Share the post "Jim Laughland: A Living Legend at Camp Perry"
Shooting Sports USA has published an informative article covering prescription eyewear for shooters. In The Right Rx for Aging Eyes, writer Chris Christian reviews vision issues with Doctor of Optometry Alexis Rodriguez. Christian notes that many shooters have difficulty focusing on their sights as their eyes age. Even if you use scopes more of the time, we recommend you read this article, which explains the physiology (and bio-mechanics) of human vision.
Shooters experience vision issues as they get older, explained Dr. Rodriguez: “Presbyopia is the medical term that describes the natural deterioration of the eyes with age.” As people get older, the ability of the eyes to focus on near objects is diminished, due to the loss of elasticity of the crystalline lens inside the eye and the gradual deterioration of the ciliary muscles that help in bending the lens to focus. Rodriguez says the first symptoms usually occur around age 40, although some will experience them later. This normally starts with blurriness when looking at close objects. From that first point, this natural deterioration will continue to worsen until around the age of 65, where it normally stabilizes, and virtually all elasticity of focus is gone.
To overcome focus problems associated with aging eyes, Dr. Rodriguez often recommends a modified bifocal design for shooters. The lower insert is set to the shooter’s Sight Distance (SD) instead of a standard “reading” distance and the insert lens is moved upwards in the lens to a point in line with the bottom of the pupil. This allows the shooter to maintain a constant head position to access the lower lens and reduces image jump.
Based on the questions we get on a daily basis on our 800 (Customer Support) line, twist is one of the most misunderstood subjects in the gun field. So let’s look deeper into this mystery and get a better understanding of what twist really means.
When you see the term 1:14″ (1-14) or 1:9″ twist, just exactly what does this mean? A rifle having a 1:14″ twist means the bullet will rotate one complete revolution every fourteen inches of the barrel. Naturally a 1:9″ turns one time every nine inches that it travels down the barrel. Now, here’s something that some people have trouble with. I’ve had calls from shooters thinking that a 1:14″ twist was faster than a 1:9″ because the number was higher with the 1:14″. The easiest way to remember this is the higher the number, the slower the twist rate is.
Now, the biggest misconception is that if a shooter has a .223 with a 1:8″ twist, his rifle won’t stabilize a 55gr bullet or anything lighter. So let’s look at what is required. The longer a bullet is for its diameter, the faster the twist has to be to stabilize it. In the case of the .223 with a 1:8″ twist, this was designed to stabilize 80gr bullets in this diameter. In truth the opposite is true. A 1:8″ will spin a 55gr faster than what is required in order to stabilize that length of bullet. If you have a bullet with good concentricity in its jacket, over-spinning it will not [normally] hurt its accuracy potential. [Editor’s Note: In addition, the faster twist rate will not, normally, decrease velocity significantly. That’s been confirmed by testing done by Bryan Litz’s Applied Ballistics Labs. There may be some minor speed loss.]
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.
Think of it like tires on your truck. If you have a new set of tires put on your truck, and they balance them proper at the tire shop, you can drive down a street in town at 35 MPH and they spin perfect. You can get out on the highway and drive 65 MPH and they still spin perfect. A bullet acts the same way.
Once I loaded some 35gr HP bullets in a 22-250 Ackley with a 1:8″ twist. After putting three shots down range, the average velocity was 4584 FPS with an RPM level of 412,560. The group measured .750″ at 100 yards. This is a clear example that it is hard to over-stabilize a good bullet.
Twist-rate illustration by Erik Dahlberg courtesy FireArmsID.com. Krieger barrel photo courtesy GS Arizona.
Share the post "Twist Rate: Common Misconceptions about Twist and Stabilization"
Don’t Be “That Guy” (The Bad Apple on the Firing Line)
By SFC Norman Anderson, USAMU Service Rifle Team Member
You know the guy, he’s still talking at the coffee jug when his preparation period begins, then his magazines aren’t loaded when the command “STAND” is given, and finally, he doesn’t know the rules when he argues with the block officer as his target comes up marked “9 and No”. Although this guy might be the highlight of the “after match” activities, he is the proverbial bad apple on the firing line. With this example fresh in your mind, let’s go over how not to be “that guy”.
While the sport of High Power shooting is a hobby for most, all are passionate about performance throughout the day. In order to achieve your maximum performance each and every day, it is essential that you conduct yourself as a professional competitor. As a competitor, you have a personal responsibility to know the course of fire as well as the rules and procedures that apply to it and to be prepared to follow them. Knowing this will not only make you a better competitor, but it will enable you to resolve situations with other targets besides your own. So what does all this mean? I’ll explain…
Know the Course of Fire
Know the course of fire. It sounds easy enough, as we all shoot plenty of matches, but it’s more than that. If you think about it, how many people in the pits, for example, do not really know what is happening on the firing line? This leads to targets being pulled early during a rapid fire string or missing a shot during a slow fire string. In cases like this, the result is the same, delays in the match and upset competitors. To avoid being “that guy,” it is imperative that you stay tuned to the events as the day progresses. When you are at the range shooting a match, be at the range shooting the match.
At any firearms competition — be sure you know (and understand) the course of fire.
Know the Rules
Now, let’s discuss rules. As you have probably heard more than once, the rulebook is your best friend. Here is why. I can virtually guarantee that most competitors know some of the rules based only on the old “this is how we do it at home” adage. The funny part of that is, the same green NRA rulebook and orange CMP rulebooks are used to govern High Power matches all over the country.*
It is vital that all shooters be familiar with the rules as they are written, not with “how they are applied at home”. This creates consistency and continuity in how matches are conducted, from local club matches to state tournaments to National Championships. Knowledge is power when it comes to scoring targets under contention, what to do in the case of a malfunction, or even how to file a protest correctly. These rules are in place for a reason and it benefits everyone to both know and operate by these rules.
Maintain Composure and Humility — Exhibit Good Sportsmanship
One aspect of competing that cannot be forgotten is bearing. As I mentioned earlier, you must be prepared for both good and bad to happen. All too often we all see “that guy” (or that “that guy’s” gear) flying off of the firing line in disgust. Remember that we all must maintain our composure and humility in all conditions, not matter what happens. After all, it’s just a game. To put it into perspective, if it were easy, attendance would be a lot higher. Sportsmanship must be displayed in an effort to keep from ruining the day for all those around you. It doesn’t cost anything to smile, and smiling never killed anyone. So turn that frown upside down and keep on marching, better days will come.
Like a Boy Scout — Always Be Prepared
Lastly, I would like to cover preparedness. Being prepared goes beyond simply having your magazines loaded and a zero on your rifle. It means approaching the firing line, knowing what you are about to do, being ready for what is going to happen (good or bad), and being ready for the results. If you approach the firing line to merely shoot 10 shots standing in your next LEG match, you are not going to be pleased with the result. You must be prepared mentally and physically, not only for the next stage, but also the next shot. By being prepared physically (equipment ready), you give yourself peace of mind which is an essential part of being prepared mentally, and by being prepared mentally, you are less likely to become distracted and are more likely to maintain focus for each and every shot.
Conclusion — Informed Competitors Make for Better Matches
The culmination of these efforts results in a shooter that knows how to be ready for success on the range, but also and perhaps more importantly, a shooter who knows what it means to be a competitor. When you have a range full of competitors who know and follow the rules and proper match procedures, the match runs smoothly, everyone shoots well, and a good time is had by all. In the end, isn’t that what it’s all about?
* After this article was originally written, the CMP separated its rules into two different Rulebooks:
The 2016 4th Edition of the CMP Competition Rules for CMP Games Rifle and Pistol Matches governs all CMP-sanctioned matches for As-Issued Military Rifle and Pistol events including Special EIC Matches that are fired with As-Issued Military Rifles or Pistols.
The 2016 20th Edition of the CMP Competition Rules for Service Rifle and Service Pistol governs sponsored and sanctioned matches for Service Rifle, Service Pistol and .22 Rimfire Pistol events, including National Trophy Rifle and Pistol Matches, Excellence-In-Competition (EIC) matches and other CMP-sanctioned competitions.
With the Republican (GOP) Convention recently concluded in Cleveland, readers have asked: “What is the official Republican Party position on the Second Amendment and gun rights?” Here is the section of the Republican Platform concerning gun issues, quoted word for word:
The Second Amendment: Our Right to Keep and Bear Arms
We uphold the right of individuals to keep and bear arms, a natural inalienable right that predates the Constitution and is secured by the Second Amendment. Lawful gun ownership enables Americans to exercise their God-given right of self-defense for the safety of their homes, their loved ones, and their communities.
We salute the Republican Congress for defending the right to keep and bear arms by preventing the President from installing a new liberal majority on the Supreme Court. The confirmation to the Court of additional anti-gun justices would eviscerate the Second Amendment’s fundamental protections. Already, local officials in the nation’s capital and elsewhere are defying the Court’s decisions upholding an individual right to bear arms as affirmed by the Supreme Court in Heller and McDonald. We support firearm reciprocity legislation to recognize the right of law-abiding Americans to carry firearms to protect themselves and their families in all 50 states. We support constitutional carry statutes and salute the states that have passed them. We oppose ill-conceived laws that would restrict magazine capacity or ban the sale of the most popular and common modern rifle. We also oppose any effort to deprive individuals of their right to keep and bear arms without due process of law.
We condemn frivolous lawsuits against gun manufacturers and the current Administration’s illegal harassment of firearm dealers. We oppose federal licensing or registration of law-abiding gun owners, registration of ammunition, and restoration of the ill-fated Clinton gun ban. We call for a thorough investigation — by a new Republican administration — of the deadly “Fast and Furious” operation perpetrated by Department of Justice officials who approved and allowed illegal sales of
guns to known violent criminals.
PrecisionRifleBlog.com (PRB) recently published results from a field test PRB conducted to quantify the temperature stability of the popular Hodgdon H4350 and Varget powders and compare those to IMR’s new Enduron line of powders, specifically IMR 4166 and 4451.
Hodgdon Extreme Series powders have attracted quite a fan base, with over 90% of the top shooters in the Precision Rifle Series choosing to run one of those powders. IMR recently released a new line of powders “with Enduron Technology” — which is also marketed to have “extreme temperature stability”. Sounds familiar! These new powders should compete directly with the Hodgdon Extreme Series, which gives shooters more temp-stable powder options to consider.
The top shooters in the PRS and veteran long-range shooters in other disciplines have learned to value a temperature-stable powder. That’s because a change in temperature can affect the trajectory or “flight path” of the bullet in two well-known ways:
1. Assuming all other environmental conditions remain the same, an increase in air temperature will cause a flatter trajectory due to a lower air density (easier for the bullet to cut through the air).
2. The same increase in temperature also causes the nitrocellulose-based powder inside the cartridge to burn at a higher rate, producing approximately four times the Point of Impact (POI) shift than just air temperature alone. (SEE: Temperature Effects On Zero on KestrelMeters.com.)
“The initial heat condition of your powder will affect the burn rate,” Bryan Litz explained at a recent Applied Ballistics Seminar. That means swings in ambient outside temperature can affect your internal ballistics, which will directly affect your muzzle velocity, which will change your bullet’s trajectory. Some powders are more affected by changes in temperature than others. So if your goal is first-shot hits and you may shoot in a variety of conditions — you should care about temperature stable powders.
The folks at PrecisionRifleBlog.com meticulously loaded 6.5×47 Lapua ammo with each powder using some of the best equipment available. This included the top-of-the-line Prometheus Gen II Powder Scale, which is capable of loading to the nearest kernel of powder. This ensured the powder charges were identical for each round of ammo. PRB’s testers explain the full set of equipment and steps in their loading process in the Full Test Report.
Once they had a couple dozen rounds loaded with each powder, they went and shot them with each powder at 25° F, 65° F, and 140° F. The muzzle velocity of each shot was recorded using both a LabRadar Doppler Radar and a MagnetoSpeed Chronograph. The LabRadar is a new type of device that allows you to measure muzzle velocity within at least +/- 0.1% of the reading.
Here are the results from the PRB Powder Temp Stability Tests:
You can see Hodgdon H4350 had the least variance in muzzle velocity, with just 25 fps over the 115° swing in temperature! That is very, very low. Hodgdon Varget was the second least temperature sensitive powder in this test, with 46 fps of variance in muzzle velocity between temperatures of 25° F and 140° F. IMR 4166 performed very similar to Varget, and proved to be fairly insensitive to large swings in temperature. IMR 4451 had the largest swing in muzzle velocity of the powders tested, but keep in mind just 68 fps over 115° F swing is still a good performance.
Most powders aren’t specially formulated to be temperature stable. So they would likely show much larger swings than what these four top-performing powders showed.
PRB’s test team also noticed other interesting trends in the data. For example, variation in velocity does NOT appear to be linear across the full range of temperatures. By that, they mean the change per degree from 20° to 65° might be smaller or larger than the change per degree from 65° to 140°.