Lapua, maker of premium brass, bullets, and loaded ammo, has released a new, state-of-the-art Ballistics program that runs on smartphones and mobile devices. The all-new Lapua Ballistics Mobile App is the first mobile ballistics app utilizing the 6DOF calculation model. 6DOF refers to “Six Degrees of Freedom”, referring to the multiple variables the software calculates. As explained below, a 6DOF solver can account for 3 components of movement PLUS 3 components of rotation. Of course, as with other ballistics software, the Lapua Mobile App looks at Bullet BC, velocity, and cross-wind effects. This software can also account for subtle, extreme long range factors such as the Coriolis Effect.
Notably, the new Lapua Ballistics App includes a library of up-to-date bullet profiles based on extensive field tests with Doppler Radar. Having an ultra-sophisticated 6DOF solver combined with Doppler Radar data makes the Lapua Mobile App one of the most accurate ballistics Apps on the market. Lapua Ballistics offers the latest, Doppler-proven Lapua cartridge and bullet data for you to combine with your firearm and local weather information. The App also includes the option to define custom bullets.
The Lapua Ballistics App is available for Android and iOS smart phones and mobile devices free of charge. For more info, visit www.lapua.com/lapuaballisticsapp.
6DOF, the most accurate calculation method. Lapua cartridge / bullet information. Distance, wind speed and angle. outputs numerical, reticle, table and graph views, metric and imperial values. Set Point Blank-range to different sight-in distances and impact windows. Define custom bullets ( BC G1 or G7 and Siacci method), Pre-set max 4 powder temperature.Sight-in-POI, Coriolis calculation
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The folks at PMA Tool, makers of arbor presses, neck-turning tools, and other case-prep tools, offered some good advice about case trimming on the PMA Tool Website. Here we reprint a PMA article that explains case trimming basics and helps you choose the right case-trimming tool for your needs.
Case Trimming Basics
Trimming the cartridge case to the proper length is a crucial step in case preparation that should not be overlooked or underestimated. The cartridge case or the rifle can be damaged, or even worse you get badly injured. In most instances cases should be trimmed after firing and sizing. Trimming new brass is necessary for a lot of wildcats and can be beneficial in some instances, but by and large, trimming new brass is not necessary for most situations (unless you are neck-turning). Cases should be trimmed after you have sized the case, because the expander ball on the decapping pin can (and will) stretch the neck. Those of us who neck size should get into the habit of trimming after sizing as well. This is a good rule of thumb to go by, and hopefully it will keep you safe during the reloading and shooting process.
There are so many case trimmers out there that work, deciding which one is right for you can be confusing. Even though I have trimmed thousands of cases, using about every method possible, I can’t answer the question of what case trimmer is right for you because of all the variables that may be involved. I can, however shed some light on the subject.
The two most popular designs of trimmers either index (1) off the base or the head of the case, (2) off the shoulder or datum line of the case. There are pros and cons to each and it all depends on what you are willing to live with.
Indexing off the Base (Case Head)
Let’s talk about the first one I have listed, indexing off the base, or the head of the case. The pros to this method are that you can achieve a very accurate over all length and that is after all, what it is all about. The cons to this method are that you can get some variation doing it this way. Let me explain, the base is not always square to the body or can be damaged during firing especially if it is fired through a military style rifle with a very aggressive ejector. These cases should be discarded, but sometimes they can be overlooked. This condition can lead to an over all length that is incorrect. The case head being out of square will be corrected upon firing, however that case will wind up being shorter than the rest of your cases, possibly creating a difference in the neck tension on the bullet. The more you can do to eliminate variables in your reloads the better off you are going to be. This method can also be very slow, and if the user gets careless the result will be a inconsistent over all length.
Indexing off the Shoulder (Datum Line)
The second method I mentioned, trimming off the shoulder or the datum line of the case, has its pros as well. I have found this to be the quickest of the methods and very accurate as well. After the case has been sized through the die the dimensions (particularly the headspace) of the cases are usually very uniform and exact, this allows the case to be trimmed by indexing off the shoulder. This method can be done very quickly, by hand, or by powering either the case, or the trimmer. You also don’t have to worry about the case heads being out of square with the body using this method. Generally the trimming time is cut in half, and this leads to greater focus on the job, without becoming careless. [Editor’s Note: The World’s Finest Trimmer (WFT) is one power device that indexes off the shoulder datum. It works fast and is very precise. The new WFT 2 Model with interchangeable trim chambers works with multiple cartridge types.]
The choice is yours to make. I hope that this was some help to you, whether you are looking for your first trimmer or looking to replace the trimmer you have. Just remember to always put safety first and accuracy second, and you will start making little bug holes in no time.
Story Tip by EdLongrange. User Submissions are welcome.
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Here’s a tip for guys who shoot the 6 PPC, 6 Dasher, or other wildcat cartridges that require fire-forming. Use your fouler shots to fire-form new cases. That way your fouler shots do “double-duty” and you get your brass fire-formed without putting extra rounds through your expensive barrel.
This procedure is recommended by Joel Kendrick, the 2004 IBS 600-yard Shooter of the Year. After he cleans his barrel, Joel knows it takes two or three shots to foul in the bore before accuracy returns. When shooting his PPC, Joel uses those fouler shots to fire-form his new brass. Joel explains: “I like to have relatively new brass always ready. By fire-forming a couple cases after each barrel-cleaning during a match, by the end of the weekend I’ve got a dozen or more freshly fire-formed cases to put into the rotation. If you do this with your fouler shots you get your fire-forming accomplished without using up any extra barrel life.”
We thank Joel for this smart suggestion. For those who do not have a dedicated barrel for fire-forming, this should help keep your round-count down. Joe currently works as the Supplier Quality Process Engineer for MMI-TruTec, a company that offers barrel surface coatings that can further extend your barrel life.
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Here’s a simple solution for lumpy front sandbags. Cut a small block the width of your fore-end and place that in the front bag between matches. You can tap it down firmly with a rubber mallet. This will keep the front bag nice and square, without bunching up in the center. That will help your rifle track straight and true. Rick Beginski uses wood (see photo), while our friend John Southwick uses a small block of metal. The metal block might work a little better, but the wood version is easier to make with simple tools. John Loh of JJ Industries offers a slick Delrin block with a built-in bubble level. Loh’s block helps ensure that the actual top surface of your front bag is level, as distinct from the front rest assembly.
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Even with high-quality brass from Lapua, Norma, and RWS, occasionally you may find one or two cases per box which have a small flake or obstruction in the flash-hole. This will appear like a thin crescent on one side of the flash hole (see photo). You should inspect ALL new brass before loading to identify any pieces with a partially-obstructed flash hole. It’s a good idea to remove any flake or thin crescent left as an artifact of the flash-hole forming process. Because the flash-hole itself is normally centered and of the correct diameter, it is not necessary to ream the flash-hole to a larger diameter. All you really need to do is remove the small obstruction(s). This can be done quickly with inexpensive tools.
Use a Small Pin Vise to Remove Flash-Hole Obstructions
Folks have asked if there is a tool that can remove obstructions from a Lapua small, BR-sized flash hole without opening the hole size. The Lapua PPC/BR flash hole is spec’d at 1.5mm, which works out to 0.059055″. Most of the PPC/BR flash-hole uniforming tools on the market use a 1/16″ bit which is nominally 0.0625″, but these often run oversize — up to 0.066″.
If you want to just clear out any obstructions in the flash hole, without increasing the flash hole diameter, you can use an inexpensive “pin vise” with an appropriate drill bit. For $1.00, eHobbyTools.com sells a 1.5mm drill bit, item 79186, that matches the Lapua flash hole exactly. Other vendors offer a #53 pin vise drill bit that measures .0595″ or .060″ (depending or source). An 0.0595″ bit is close enough. You can find pin vises and these small-diameter drill bits at hobby stores.
For quite some time, Sinclair Int’l has sold a similar device for small (PPC and BR-size) flash holes. Like the 07-3081 unit for large flash holes, the 073000 Reamer for small flash holes works from the outside, so it can index off the primer pocket. It reams to .0625″, and also costs $39.99. The standard dimension for Lapua 220 Russian and 6mmBR flash holes is 1.5mm or .0590″. This tool will permit standard-size decapping rods with .0625″ tips to work without binding. However, note that both Forster and Redding normally supply .057″ decapping pins with their PPC and BR dies. So, it is NOT necessary to ream your Lapua BR/PPC flashholes, unless you prefer to do so for uniformity. It IS, however, a good idea to check BR/PPC flash holes for burrs before loading the first time.
NOTE: If you purchase either the 073081 or 073000 Sinclair Flash Hole Reamer tools, we recommend you mic the cutter tip before you process a bunch of cases. Sometimes a tip comes through that is oversize. This will ream the flash holes larger than you may intend.
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Tech Milestone — Norm Crawford won the 2016 Wimbledon Cup at Camp Perry using a carbon-fiber composite barrel. That’s a first for composite barrel technology.
With a score of 200-16X, Norman Crawford won the Wimbledon Cup Match during the 2016 National Long Range Rifle Championships using a 32″ Proof Research carbon-fiber composite barrel chambered in .284 Shehane. The Wimbledon Cup Match, a prestigious 1,000-yard shooting competition, dates back to 1875. The current course of fire consists of 20 timed shots, fired from prone. Crawford’s win represents the first time in the Cup’s 141-year history that it has been won with anything other than an all-steel barrel. The Proof Research barrel features a steel core with an external multi-axis carbon wrap.
Crawford’s Wimbledon Cup win really is an important technological milestone. Crawford’s performance may encourage other competitors to consider steel/carbon composite barrels for a variety of shooting disciplines. Without question, composite technology barrels offer significant weight-savings over conventional all-steel barrels. And Crawford proved that a composite barrel can deliver winning accuracy, at least in a sling/prone discipline.
“I don’t know of anyone else in this sport using a carbon fiber [composite] barrel,” said Crawford, who has been shooting Proof composite barrels since 2013.
“The benefits over a steel barrel are that you get a larger-diameter, stiffer, faster-cooling barrel that weighs less than a standard, medium Palma-taper barrel. [There is] no real downside I’ve been able to identify in three years of shooting them. All five Proof barrels I own are capable of winning any match — providing I do my part.”
A 30-year Army vet and former Army Special Operations Sniper, Crawford has been shooting competitively since 1990. He has won many major titles, including the NRA National Long Range Championship in 2005. His 2016 Wimbledon Cup victory was his second — Norm also won the Cup in 2003. A three-time member of the U.S. Rifle Team at the World Championships, Crawford also used a Proof Research barrel to tie the national record for a 600-yard Any Gun, Any Sight competition in North Carolina last November, one of five national records he has set or tied during his shooting career.
Proof Research CEO Larry Murphy praised Crawford: “We are honored that Norm chose our barrel to go up against the best shooters in the world with. By putting our barrels to the test in intense competition, he pushes us to do our best as well.”
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Brownell’s has prepared a useful video showing how to remove light rust from a firearm. This shows how to use soft cloths, polishes, and 0000 steel wool to eliminate light surface rust. CAUTION — if you have a very high gloss blued finish, ANY abrasive and even the finest grade of oiled steel wool can scratch or alter the finish. With something like a $1200.00 “Royal Blue” Colt Python, it may be better to tolerate a few small pits than to work it over with steel wool.
Watch Brownell’s Video on Rust Removal
Brownell’s technician, Steve Ostrem, notes that many things can promote rust — some you might not expect. In addition to moisture in the air, rust can be caused by the salts and oils from your hands, sweat, blood, or even insect repellent. Ostrem also observes that temperature changes can produce condensation which may lead to rust inside the gun that you don’t even notice: “In the real world we know that if you take the gun outside, sooner or later, it’s going to rust. When you come inside, wipe the gun down the first opportunity you get. If you bring a cold gun into a warm, humid house, you’re going to have an instant coating of moisture… make sure you get the gun dried off and you’ll avoid a lot of problems.”
We’ve conducted a comprehensive test of corrosion-fighters. Among the best products to prevent rust are Boeshield T-9, Corrosion-X, and Eezox. Break-Free also works well, but it leaves a somewhat greasy residue, and it did not perform as well during long-term salt exposure as did the other three products.
For long-term storage, nothing beats a coating of Cosmoline, Rig or similar grease. This provides a barrier layer that blocks the oxidation process, which is how rust forms. These greases performed extremely well in a comparison test of Rust Preventative Products performed by Brownell’s. CLICK HERE for Comparison Test.
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Can you guess what your next barrel will weigh? In many competition disciplines, “making weight” is a serious concern when putting together a new match rifle. A Light Varmint short-range Benchrest rifle cannot exceed 10.5 pounds including scope. An F-TR rifle is limited to 18 pounds, 2 oz. (8.25 kg) with bipod.
One of the heaviest items on most rifles is the barrel. If your barrel comes in much heavier than expected, it can boost the overall weight of the gun significantly. Then you may have to resort to cutting the barrel, or worse yet, re-barreling, to make weight for your class. In some cases, you can remove material from the stock to save weight, but if that’s not practical, the barrel will need to go on a diet. (As a last resort, you can try fitting a lighter scope.)
Is there a reliable way to predict, in advance, how much a finished barrel will weigh? The answer is “yes”. PAC-NOR Barreling of Brookings, Oregon has created a handy, web-based Barrel Weight Calculator. Just log on to Pac-Nor’s website and the calculator is free to use. Pac-Nor’s Barrel Weight Calculator is pretty sophisticated, with separate data fields for Shank Diameter, Barrel Length, Bore Diameter — even length and number of flutes. Punch in your numbers, and the Barrel Weight Calculator then automatically generates the weight for 16 different “standard” contours.
Calculator Handles Custom Contours
What about custom contours? Well the Pac-Nor Barrel Weight Calculator can handle those as well. The program allows input of eight different dimensional measurements taken along the barrel’s finished length, from breech to muzzle. You can use this “custom contour” feature when calculating the weight of another manufacturer’s barrel that doesn’t match any of Pac-Nor’s “standard” contours.
Caution: Same-Name Contours from Different Makers May Not be Exactly the Same
One final thing to remember when using the Barrel Weight Calculator is that not all “standard” contours are exactly the same, as produced by different barrel-makers. A Medium Palma contour from Pac-Nor may be slightly different dimensionally from a Krieger Medium Palma barrel. When using the Pac-Nor Barrel Weight Calculator to “spec out” the weight of a barrel from a different manufacturer, we recommend you get the exact dimensions from your barrel-maker. If these are different that Pac-Nor’s default dimensions, use the “custom contour” calculator fields to enter the true specs for your brand of barrel.
Smart Advice — Give Yourself Some Leeway
While Pac-Nor’s Barrel Weight Calculator is very precise (because barrel steel is quite uniform by volume), you will see some small variances in finished weight based on the final chambering process. The length of the threaded section (tenon) will vary from one action type to another. In addition, the size and shape of the chamber can make a difference in barrel weight, even with two barrels of the same nominal caliber. Even the type of crown can make a slight difference in overall weight. This means that the barrel your smith puts on your gun may end up slightly heavier or lighter than the Pac-Nor calculation. That’s not a fault of the program — it’s simply because the program isn’t set up to account for chamber volume or tenon length.
What does this mean? In practical terms — you should give yourself some “wiggle room” in your planned rifle build. Unless you’re able to shave weight from your stock, do NOT spec your gun at one or two ounces under max based on the Pac-Nor calculator output. That said, the Pac-Nor Barrel Weight Calculator is still a very helpful, important tool. When laying out the specs for a rifle in any weight-restricted class, you should always “run the numbers” through a weight calculator such as the one provided by Pac-Nor. This can avoid costly and frustrating problems down the road.
Credit Edlongrange for finding the Pac-Nor Calculator
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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.
Do you know what the inside of a rifle chamber (and throat zone) really looks like? Do you understand the concept of headspace and why it’s important? If not, you should read the Brownells GunTech article Gauging Success – Minimum Headspace and Maximum COL. This article explains the basics of headspace and shows how to measure headspace (and length to lands) in your barrels with precision. The article also explains how to adjust your full-length sizing dies to “bump the shoulder” as needed.
Why is headspace important? The article explains: “Controlling headspace and setting proper C.O.L. also represent improved safety and reduced cost of handloading. Excessive headspace can cause case head separation and gases in excess of 60,000 PSI escaping from a rifle’s chamber. Too little headspace can result in a chamber forced bullet crimp and a bullet that becomes an obstruction more than a properly secured projectile. Excessive C.O.L. can result in a rifling-bound bullet, a condition that could result in spikes of excessive pressure.” [Editor’s NOTE: It is common for competitive benchrest shooters to seat bullets into the rifling. This can be done safely if you reduce your loads accordingly. With some bullets we often see best accuracy .010″ (or more) into the lands. However, this can generate more pressure than the same bullet seated .010″ away from initial lands contact. As with all reloading, start low and work up gradually.]
How is headspace specified? Most cartridges used within the United States are defined within ANSI/SAAMI Z299.3-4. Brownells explains: “In the case of the .243 Winchester, as an example, there are pressure specifications, cartridge drawings and, as pictured above, chamber drawings. Armed with a chamber drawing, each manufacturer producing a firearm for the .243 Winchester knows the proper standard dimension to cut chambers and set headspace. Notice there are two headspace reference dimensions for the chamber. The upper is a place in the chamber where the shoulder is .400″ in diameter; the “datum” or “basic” line. The lower is the 1.630″~1.640″ minimum – maximum dimension from the breech face (bolt face) to that point in the chamber that measures .400″.”
The actual headspace of any firearm is the distance from the breech face to the point in the chamber that is intended to prevent forward motion of a cartridge.
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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.
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Forest of Windflags at World Benchrest Championships in France in 2011
There’s a simple, inexpensive “miracle device” that can cut your groups in half. If you’re not using this device, you’re giving away accuracy. The “miracle device” to which we refer is a simple wind indicator aka “windflag”. Using windflags may actually improve your accuracy on target much more than weighing charges to the kernel, or spending your life savings on the “latest and greatest” hardware.
Remarkably, many shooters who spend $3000.00 or more on a precision rifle never bother to set up windflags, or even simple wood stakes with some ribbon to show the wind. Whether you’re a competitive shooter, a varminter, or someone who just likes to punch small groups, you should always take a set of windflags (or some kind of wind indicators) when you head to the range or the prairie dog fields. And yes, if you pay attention to your windflags, you can easily cut your group sizes in half. Here’s proof…
Miss a 5 mph Shift and Double Your Group Size
The table below records the effect of a 5 mph crosswind at 100, 200, and 300 yards. You may be thinking, “well, I’d never miss a 5 mph let-off.” Consider this — if a gentle 2.5 mph breeze switches from 3 o’clock (R to L) to 9 o’clock (L to R), you’ve just missed a 5 mph net change. What will that do to your group? Look at the table to find out.
Values from Point Blank Ballistics software for 500′ elevation and 70° temperature.
Imagine you have a 6mm rifle that shoots half-MOA consistently in no-wind conditions. What happens if you miss a 5 mph shift (the equivalent of a full reversal of a 2.5 mph crosswind)? Well, if you’re shooting a 68gr flatbase bullet, your shot is going to move about 0.49″ at 100 yards, nearly doubling your group size. With a 105gr VLD, the bullet moves 0.28″ … not as much to be sure, but still enough to ruin a nice small group. What about an AR15, shooting 55-grainers at 3300 fps? Well, if you miss that same 5 mph shift, your low-BC bullet moves 0.68″. That pushes a half-inch group well past an inch. If you had a half-MOA capable AR, now it’s shooting worse than 1 MOA. And, as you might expect, the wind effects at 200 and 300 yards are even more dramatic. If you miss a 5 mph, full-value wind change, your 300-yard group could easily expand by 2.5″ or more.
If you’ve already invested in an accurate rifle with a good barrel, you are “throwing away” accuracy if you shoot without wind flags. You can spend a ton of money on fancy shooting accessories (such as expensive front rests and spotting scopes) but, dollar for dollar, nothing will potentially improve your shooting as much as a good set of windflags, used religiously.
If you asked a group of shooters to explain the difference between CUP and PSI, the majority would probably not be able to give a precise answer. But, for safety reasons, it’s very important that all hand-loaders understand these important terms and how they express cartridge pressures.
The ANSI / SAAMI group, short for “American National Standard Institute” and “Sporting Arms and Ammunition Manufacturers’ Institute”, have made available some time back the voluntary industry performance standards for pressure and velocity of centerfire rifle sporting ammunition for the use of commercial manufacturers. [These standards for] individual cartridges [include] the velocity on the basis of the nominal mean velocity from each, the maximum average pressure (MAP) for each, and cartridge and chamber drawings with dimensions included. The cartridge drawings can be seen by searching the internet and using the phrase ‘308 SAAMI’ will get you the .308 Winchester in PDF form. What I really wanted to discuss today was the differences between the two accepted methods of obtaining pressure listings. The Pounds per Square Inch (PSI) and the older Copper Units of Pressure (CUP) version can both be found in the PDF pamphlet.
CUP Pressure Measurement
The CUP system uses a copper crush cylinder which is compressed by a piston fitted to a piston hole into the chamber of the test barrel. Pressure generated by the burning propellant causes the piston to move and compress the copper cylinder. This will give it a specific measurable size that can be compared to a set standard. At right is a photo of a case that was used in this method and you can see the ring left by the piston hole.
PSI Pressure Measurement
What the book lists as the preferred method is the PSI (pounds per square inch or, more accurately, pound-force per square inch) version using a piezoelectric transducer system with the transducer flush mounted in the chamber of the test barrel. Pressure developed by the burning propellant pushes on the transducer through the case wall causing it to deflect and make a measurable electric charge.
Q: Is there a standardized correlation or mathematical conversion ratio between CUP and PSI values?
Mahin: As far as I can tell (and anyone else can tell me) … there is no [standard conversion ratio or] correlation between them. An example of this is the .223 Remington cartridge that lists a MAP of 52,000 CUP / 55,000 PSI but a .308 Winchester lists a 52,000 CUP / 62,000 PSI and a 30-30 lists a 38,000 CUP / 42,000 PSI. It leaves me scratching my head also but it is what it is. The two different methods will show up in listed powder data[.]
So the question on most of your minds is what does my favorite pet load give for pressure? The truth is the only way to know for sure is to get the specialized equipment and test your own components but this is going to be way out of reach for the average shooter, myself included. The reality is that as long as you are using printed data and working up from a safe start load within it, you should be under the listed MAP and have no reason for concern. Being specific in your components and going to the load data representing the bullet from a specific cartridge will help get you safe accuracy. [With a .308 Winchester] if you are to use the 1% rule and work up [from a starting load] in 0.4 grain increments, you should be able to find an accuracy load that will suit your needs without seeing pressure signs doing it. This is a key to component longevity and is the same thing we advise [via our customer service lines] every day. Till next time, be safe and enjoy your shooting.
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Forum member Mike T. (aka “Watercam”), has cleverly adapted a tubegun cheek piece to conventional fiberglass and wood stocks. The cheek piece hardware comes from Competition Machine and is the same as used on Gary Eliseo’s tubegun stocks. Here is Watercam’s Project Report:
Installing Tubegun Cheek Piece on Conventional Gun Stock
All of my match rifles are equipped with thumb-wheel adjustable cheek pieces for the best of reasons — adjustments can be made while in position, on target. I’ve learned that variations in position, terrain, and vertical angle all demand adjustability to achieve optimal cheek weld.
I wanted a cheek piece for my hunting and tactical type stocks that gave the same adjustability without having to cut a chunk off of my butt stocks. It needed to be affordable and easy to install. I also wanted a unit that would not push my head laterally away from the centerline of the scope or iron sights. Turns out I already had what I needed on my Gary Eliseo B-1 tubegun. I ran the idea past Gary, who said: “If you’ll be the guinea pig I’ll send the hardware”.
Using Gary’s hardware, I mounted Eliseo alloy thumb-wheel adjustable cheek pieces on a Bell & Carlson Medalist hunting stock and a Boyd’s laminate tactical stock. Read Forum Discussion.
Building Version One on Bell & Calson Stock
I had a Bell & Carlson Medalist stock for a Mauser 98 chambered in 9.3×62. This test rifle was enough of a thumper to reveal if the metal cheek piece could handle strong recoil.
I started by drilling three 1/2″ holes into the top of the comb to match the two pillars and one threaded shaft on the cheek piece. I used aluminum tubing to make guides for each and epoxied them in place. Inletting the oval hole for the thumb wheel was reasonably straight forward and the fiber reinforced foam in the buttstock offered enough support. A large flat washer epoxied underneath where the thumbwheel lay gave a smooth bearing surface. Total adjustment (with 2.25″ pillars and shafts) is just about an inch. I chose to trim the bottom of the skirt of Gary’s cheek plate so as to allow better position behind the scope for me and allow maximum adjustment even with the cheek piece of the stock. Set screws could be used instead of the thumb-wheel or in conjunction with it. In the end it was exactly what I envisioned and works great! The only thing left to do is paint the metal to match the stock.
Version Two — Installed on Boyds Laminated Tactical Stock
Watercam’s second metal cheek piece installation was on a laminated tactical stock. This Boyds stock did have a movable comb, but the original adjustable cheek section was too awkward to adjust from position. So I adapted the Eliseo cheek piece to to the Boyds stock, as you can see:
Cheek piece installation for both stocks was straight-forward, and the new cheek pieces work every bit as well the systems on my match rifles. Aluminum tubes epoxied in place guide the rods and threaded shank. A matching-diameter flat washer epoxied under the wheel provides smooth bearing surface. The glass-filled filler of the butt stock is plenty strong enough to support the unit. A set screw and knob can be added to lock in changes if so desired.
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In this video, Bryan Litz of Applied Ballistics focuses on training. Bryan says that training is key for success in Long Range shooting: “Training in the sense that you want to want to refine your fundamentals of marksmanship — your sight alignment, your trigger control. You should practice those things enough that they become second nature and you don’t have to think about them. Keep in mind, it’s not just good enough to train, you have to learn how to train. You need to learn how to practice effectively, to get the most out of everything you do.”
Bryan says that success in Long Range shooting is not just about the hardware. It’s what’s between your ears that really counts: “The most important element in Long Range shooting is your knowledge — your understanding and practice of fundamentals of marksmanship, as well as your understanding of ballistics. You have to be able to fire the rifle, execute good shots that will put your rounds on target, but you also need to make intelligent sight corrections that will accurately account for the effects of gravity drop, and wind deflection, to center your group on those targets”.
Litz Competition Shooting Tips
Competition TIP ONE. Improving your scores in long range competition is a constant process of self-assessment. After each match, carefully analyze how you lost points and make a plan to improve. Beginning shooters will lose a lot of points to fundamental things like sight alignment and trigger control. Veteran shooters will lose far fewer points to a smaller list of mistakes. At every step along the way, always ask yourself why you’re losing points and address the issues. Sometimes the weak links that you need to work on aren’t your favorite thing to do, and success will take work in these areas as well.
Competition TIP TWO. Select your wind shooting strategy carefully. For beginners and veterans, most points are typically lost to wind. Successful shooters put a lot of thought into their approach to wind shooting. Sometimes it’s best to shoot fast and minimize the changes you’ll have to navigate. Other times it’s best to wait out a condition which may take several minutes. Develop a comfortable rest position so you have an easier time waiting when you should be waiting.
Competition TIP THREE. Actively avoid major train wrecks. Sounds obvious but it happens a lot. Select equipment that is reliable, get comfortable with it and have back-ups for important things. Don’t load on the verge of max pressure, don’t go to an important match with a barrel that’s near shot out, physically check tightness of all important screws prior to shooting each string. Observe what train wrecks you and others experience, and put measures in place to avoid them.
Here’s a significant new addition to our knowledge base for Long-Range shooting. Hornady has released a new Ballistics Calculator that employs bullet profiles derived from Doppler radar testing and 3D projectile modeling. Hornady’s Patent Pending 4DOF™ Ballistic Calculator provides trajectory solutions based on projectile Drag Coefficient (not static G1/G7 ballistic coefficients) along with the exact physical modeling of projectiles and their mass and aerodynamic properties. This new 4DOF (Four Degrees of Freedom) calculator also accounts for spin drift and the subtle VERTICAL effects of crosswinds.
We strongly recommend you watch this video from start to finish. In greater detail than is possible here, this video explains how the 4DOF System works, and why it is more sophisticated than other commercially-offered Ballistics calculators. There’s a LOT going on here…
Aerodynamic Jump from Crosswind Calculated
According to Hornady, the 4DOF Ballistics Calculator “is the first publicly-available program that will correctly calculate the vertical shift a bullet experiences as it encounters a crosswind.” This effect is called aerodynamic jump. The use of radar-derived drag profiles, correct projectile dynamics, aerodynamic jump, and spin drift enable the Hornady® 4DOF™ ballistic calculator to provide very sophisticated solutions. Hornady says its 4DOF solver is “the most accurate commercially available trajectory program … even at extreme ranges.”
“Current ballistic calculators provide three degrees of freedom in their approach — windage, elevation, and range — but treat the projectile as an inanimate lump flying through the air,” said Dave Emary, Hornady Chief Ballistician. “This program incorporates the projectile’s movement in the standard three degrees but also adds its movement about its center of gravity and subsequent angle relative to its line of flight, which is the fourth degree of freedom.”
Using Doppler radar, Hornady engineers have calculated exact drag versus velocity curves for each bullet in the 4DOF™ calculator library. This means the 4DOF™ calculator should provicde more precise long range solutions than calulators that rely on simple BC numbers or drag curves based with limited data collection points. Emary adds: “The Hornady 4DOF also accurately calculates angled shots by accounting for important conditions that [other ballistic] programs overlook.”
“This calculator doesn’t utilize BCs (Ballistic Coefficients) like other calculators,” added Jayden Quinlan, Hornady Ballistics Engineer. “Why compare the flight of your bullet to a standard G1 or G7 projectile when you can use your own projectile as the standard?” That makes sense, but users must remember that Hornady’s 4DOF projectile “library” includes mostly Hornady-made bullets. However, in addition to Hornady bullets, the 4DOF Calculator currently does list seven Berger projectiles, six Sierra projectiles, and one Lapua bullet type. For example, Sierra’s new 183gr 7mm MatchKing is listed, as is Berger’s 105gr 6mm Hybrid.
This Video Explains How to Use Hornady’s New 4DOF Ballistics Calculator
Using the 4DOF™ Ballistic Calculator:
The Hornady 4DOF Ballistic Calculator provides trajectory solutions based on projectile Drag Coefficient (not ballistic coefficients) along with exact physical modeling of the projectile and its mass and aerodynamic properties. Additionally, it calculates the vertical shift a bullet experiences as it encounters a crosswind, i.e. “aerodynamic jump”. The use of drag coefficients, projectile dynamics, aerodynamic jump, and spin drift enable the 4DOF Ballistic Calculator to accurately measure trajectories even at extreme ranges. It is ideal for both long range and moderate distances and is available for the low-drag precision bullets listed in the drop down menu of the calculator. For calculating trajectories of traditional hunting and varmint bullets using BCs (ballistic coefficients), you can use Hornady’s Standard Ballistics Calculator.
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Our take on Bore-Store Gun sleeves is simple: They work great, so buy them and use them — for ALL your valuable firearms.
These thick, synthetic-fleece sacks cushion your guns, preventing nicks and scratches. The breathable fabric wicks away moisture, and the fibers are coating with corrosion inhibitors. I personally use Bore-Stores for in-safe storage with all my guns, and I have never had one of my guns rust inside a Bore-Store, even when I lived a stone’s throw from the ocean.
Bore-Stores are offered in a wide range of sizes, so you can find something to fit everything from a Snub-nosed revolver to a 32″-barrelled 50 BMG. Rifle-size Bore Stores can be purchased for $12.00 – $21.00 from Brownells. For long F-Class or tactical rifles, we recommend the 10″x52″ Scoped Shotgun Bag, Brownells item 132-000-003. You can also order direct from the Bore-Store manufacturer, Big Spring Enterprises, www.BoreStores.com. Big Spring will also craft custom sizes on request.
Get Your Guns Out of Foam-lined Cases — They Are Rust Magnets
For long-term storage, just about the worst thing you can do (short of leaving your rifle outside in the rain) is to store firearms in tight, foam-padded cases. The foam in these cases actually collects and retains moisture from the air, acting as the perfect breeding ground for rust.
Remember, those plastic-shelled cases with foam interiors are for transport, not for long-term storage. Don’t repeat the mistake of a wealthy gun collector I know. He stored four valuable Colt Single Action Army (SAA) revolvers in individual foam-padded cases, and locked these away in his gun safe. A year later, every one of his precious SAAs had rusted, some very badly.
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It’s summer time. That means many of our readers are on the road (attending major shooting matches or enjoying summer vacations). How do you do your reloading chores while living like a Gypsy for a few weeks? Here’s a solution from Forum member Dave Gray (U.S. Army Retired).
Dave is a self-declared “full-time RVer” who spends most of his time on the road. Behind his Ram 3500 pickup, Dave tows a huge 41-foot Heartland Cyclone toy hauler featuring a 12X8 foot garage in the rear. In the rear garage area, which holds a Smart Car, Dave has set up a removable reloading bench complete with RCBS Rockchucker single stage press and Dillon progressive press.
Reloading Bench Mounts to RV Wall with Brackets
Dave explains: “I used a 2″X6″X5′ board for the bench. It’s perfect for my needs, and is easy to disassemble. I made it this small so that I can park my Smart Car in the garage during travel to my destinations. The bench, attached to the wall frames, is very solid. The presses’ centers are 3″ and 6.5″ from the brackets. [There are] four bolts on the wall into aluminum wall frame and 3 bolts in the bench. If I ever have to replace the current board, I’ll do so with oak or birch or hickory. When I’m not reloading, I remove the presses and store them in a protected space. I can easily attach other equipment to the bench by using C-Clamps.” Dave’s “rolling reloading room” looks very well thought-out. We commend Dave for his inventiveness.
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Are you a do-it-yourself kind of guy with a creative eye? Then you’ll love the Target Generator from the folks at ShooterShed.com. This free, interactive webpage allows you to design a variety of fun targets, including grids, benchrest-type Score Shooting targets, sight-in targets, and even playing card targets. Choose the paper size and orientation (vertical or horizontal), then select the number of target elements on the page. For example, you could have four (4) bulls or 52 playing cards. You can include a grid on the target, or tell the program to include load information blocks. For bullseye targets, you can control the number, color, and spacing (diameter) of the rings. LINK to TARGET GENERATOR.
The program provides a preview of each target you generate. If you like a particular design, save the file, and then print as many targets as you want. Check it out, this program is fun and handy to use. Here are four (4) targets your Editor created just for this article. With a bit of practice, you can be generating your own custom targets in minutes. Have fun.
About the Creator of the Target Generator
The excellent Target Generator program was created by Rod Brown of Sheridan, Wyoming. Rod tells us: “I build custom rifles and coach shooters. I’ve got a 100-yard range out my back door. I shoot short- and long-range benchrest competitively around the country. I’m a full-time software development consultant and an FFL holder. When I’m not developing custom software for my clients, I’m usually fiddling in the shop, building a custom benchrest rifle, traveling to a match, chambering a barrel, or reloading some ammunition.
Story tip from Boyd Allen. We welcome reader submissions.
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Think you can “get by” without protective eyewear? This story provides yet another example of why you should wear safety glasses every time you go shooting. You only have one set of eyes — they are much too precious to risk.”
Bad Primer Blasts Gas Through Side of Casehead
Our friend Grant Guess recently had a “close encounter” with a bad primer. An apparently defective primer caused part of the casehead on one of his rounds to blow out. This, in turn, allowed high pressure gas to vent through the damaged primer pocket. Take a good look, boys and girls. This is yet another very good reason to wear safety glasses. The cartridge was a 6.5-06, hand-loaded in necked-down Winchester-headstamp .270 Win brass. Grant reports:
“I had a blow-through between the primer and the primer pocket today. The action was really smoking and I got a face full of gas. This was a reasonably light charge. Thank God for safety glasses.
I should also mention that it appears there is a 3/64 hole that is halfway between the primer and the primer pocket. Like it burned a small jet hole through both of them.”
Could this happen to you? It just might. On seeing this damaged case, one of Grant’s Facebook friends, Chris D., observed: “Search the internet, you will see a lot of these pin hole ‘in the corner’ failures. Obviously Winchester has some issues with the LR primers.”
Careful Examination Reveals Apparent Primer Defect
After this incident, Grant examined the damaged case: “I pinned the flash hole and it is not over-sized or under-sized. The primer clearly has an area where it had a defect. At [50,000 CUP], it doesn’t take much of a defect to cause issues. There was a slight bit of pucker-factor on the next shot….”
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