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….”
At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
1. Precision Reloading — 10% and 15% Off Berger Bullets
Berger projectiles have won countless matches and set scores of World Records. Now you can save big bucks on match and hunting bullets from Berger Bullets in a wide variety of calibers and weights. Right now Precision Reloading is offering 10% off orders of $100 or more (Code BG8161), and 15% off orders of $500.00 or more (Code BG8165). Precision Reloading has many of the most popular Berger match projectiles in stock, including 6mm 105gr Hybrids, and 7mm 180gr Hybrids. NOTE: This special only runs for a few more days, so don’t delay!
2. Midsouth — Lyman BoreCam Digital Borescope, $222.46
Here’s a great deal on an excellent product in high demand. The Lyman BoreCam is an electro-optical borescope with a digital display. You can record “stills” on a SD card. This is one of the hottest products on the market right now. But we found some in stock at a great price. Midsouth Shooters Supply now has the BoreCam for $222.46. Grab it while you can at that price. Other online vendors are charging a LOT more. For example, the MidwayUSA price is $259.99.
3. RCBS — Buy Green, Get Green Rebate
RCBS is running a very attractive Rebate Program currently. If you spend $300.00 on qualifying products you get a $75.00 rebate. Spend $50 and get a $10.00 Rebate. This program is limited to one (1) rebate redemption per calendar year, with a maximum of $75.00. CLICK HERE for more information. NOTE: To qualify, you must supply completed RCBS rebate coupon, original UPC barcodes from package, and original cash register receipt and/or dated, itemized sales invoice.
Get RCBS Chargemaster for $225.00 After Rebate
Using this rebate, you can get an RCBS Chargemaster from Amazon.com for a “final price” of $225.00. Amazon sells the Chargemaster for exactly $300.00 which qualifies for the $75.00 rebate.
4. Natchez Shooters Supply — 325 Rounds .22 LR Ammo, $22.99
This Federal .22 LR ammo is just 7 cents per round — the kind of pricing on bulk rimfire ammo we used to see in the “good old days”. Act quickly, this $22.99 Federal .22 LR Ammo deal won’t last long. Each box contains 325 rounds — enough ammo for many sessions at the range. The bullets are 40 grains, solid lead.
5. Grafs.com — Magnetospeed Sporter $179.99
If you have been waiting to get a Magnetospeed… wait no longer. Priced at just $179.99 at Grafs.com, the Magnetospeed Sporter model costs less than half as much as Magnetospeed’s V3 models. This chronograph attaches directly to your barrel so you don’t have to go downrange to position tripods and set up skyscreens. For most people the Sporter Model contains all the features they need. Using Magnetospeed’s XFR adapter (sold separately), data can be transferred easily from the display module to your mobile device. READ Magnetospeed Sporter Review.
This is a very good spotting scope for the price. Yes it gives up some low-light performance to a spotter with an 80mm objective, but otherwise it is a good performer, and we can’t think of much that will touch this Vortex Diamondback spotting scope for anywhere near the $399.99 sale price. Choose from angled or straight version for the same $399.99 price, which includes the 20-60X zoom eyepiece.
7. Amazon — Howard Leight Electronic Earmuffs $40.97
Every shooter should own a pair of Electronic muffs, even if you prefer shooting with earplugs and/or standard muffs. Electronic muffs are great when you are doing spotting duties or are working near the firing line. They allow you to hear ordinary conversations while still providing vital hearing protection. Right now Amazon.com has the Howard Leight Impact Sport Electronic Muffs on sale for just $40.97. This is good deal — these NRR 22 muffs are currently Amazon’s #1 seller in the category. NOTE: For regular, sustained shooting we recommend muffs and/or earplugs with a higher NRR rating.
8. Amazon — Leight MAX NRR33 Earplugs, $7.58 for 50 Pairs.
These Howard Leight NRR33 Max plugs are your Editor’s favorite foam earplugs. Between shooting, motorcycling and mowing lawns, I probably have Max plugs in my ears 2-3 days a week. This is a very good price for a bulk pack of 50 pairs. And if you act soon, you can get free shipping to boot.
We first ran this story a few years back. But it’s still a very interesting subject for benchrest shooters. Shown above, the 30 BR (a 6mmBR necked up to .30 Caliber) currently rules the benchrest-for-score game. However, a 30 BR Improved offers some potential advantages, particularly when the winds are strong or tricky. In this article Al Nyhus explains his 30 BRX wildcat. Running Hodgdon H4198, Al says he gets an easy 150 -200 FPS more than the conventional 30 BR. That can translate to less drift in the wind. It also lets you pursue a higher speed node, which can lead to improved accuracy with some barrels.
Forum member Al Nyhus is a top-level score shooter who has competed successfully with the 30 BR cartridge in VFS (Varmint for Score) matches. Al has been working on an “improved” 30 BR cartridge that delivers extra velocity. Al’s 30 BRX cartridge is inspired by the 6mm BRX cartridge, popular in 600-yard benchrest and across-the-course competition. The 6mm BRX cartridge maintains the same sidewall profile and shoulder angle as the parent 6mmBR case. Likewise, the 30 BRX retains the 30° shoulder used on the popular 30 BR cartridge.
Al reports: “Thought you might like to see what I’ll be working with in my VFS gun this season. It’s a true 30 BRX — a 30 BR with the shoulder moved forward 0.100″ with the standard BR shoulder angle. Stan Ware of SGR Custom Rifles built one last season for Steve Grosvenor and I was really impressed by the performance of Steve’s gun. The 30 BR barrel on my VFS gun needed replacing, so the new 30 BRX got the nod.”
30 BRX Delivers 150-200 FPS More Velocity than 30 BR
Al says his 30 BRX gives a solid 150-200 fps speed gain over the 30 BR at the top, while needing just 2.5-3.0 more grains of Hodgdon H4198 to do so. A 30 BR case holds on average 40.8 grains of water, while the 30 BRX holds 42.3 grains (roughly 4% more). So the 30 BRX delivers a 7% increase in velocity with a mere 4% increase in H20 capacity. That’s pretty good efficiency. [Editor’s Note: Assuming 34 grains of H4198 is a typical 30 BR match load, Al’s increase of 2.5-3.0 grains for the 30 BRX represents roughly a 7.5-8.5% increase in actual powder burned. That explains the higher velocities.]
Why did Nyhus decide to try an “improved” 30 BR?
Al explains: “The 30 BRX was created to operate at a [higher] velocity level than can be achieved with the standard 30 BR case, while at the same time keeping the easy-tuning characteristics of the standard 30 BR case. We also wanted to use the same powders currently used with the 30 BR and maintain similar operating pressures.” Is the 30BRX harder to shoot because of the increased velocity? Al doesn’t think so: “In a 13.5-lb HV gun, the 30 BRX case is a pleasure to shoot with just a flea bite of recoil.”
Will the 30 BRX Replace the 30 BR in Score Competition?
The 30 BR is already an exceptionally accurate cartridge that dominates short-range Benchrest for Score competition. Will the 30 BRX make the standard 30 BR obsolete? Nyhus doesn’t think so. However, Al believes the 30 BRX offers a small but important edge in some situations: “On any given day, it’s the shooter that hits the flags best and makes the fewest mistakes that ends up on top. No amount of velocity will save you when you press the trigger at the wrong time. Missing a switch or angle change at 200 yards that results in 3/4″ of bullet displacement on the target can’t be compensated for with another 200 fps. That’s the hard fact of benchrest shooting. But on those days when, as Randy Robinett says, ‘our brains are working’, the BRX may offer enough of an advantage to turn a close-but-no-cigar 10 into an ‘X’ at 200 yards. Or turn a just-over-the-line 9 into a beggar 10.” Given the fierce competition in Score matches, an extra 10 or another X can make the difference between a podium finish and also-ran status.
Wouldn’t it be nice to have a print resource at your fingertips that has hundreds of true-size cartridge illustrations, plus technical descriptions of thousands of popular cartridge types? That could be a real time-saver. It’s no wonder this book is an Amazon best-seller in its category.
If you’re a serious shooter, the latest 5th Edition of the Ammo Encyclopedia belongs in your library. This 1008-page book by Michael Bussard is probably the most comprehensive and up-to-date book in print covering current and obsolete cartridges and shotshells. The Ammo Encyclopedia is a massive resource work. The 5th Edition now boasts 105 chapters, covering thousands of handgun, rifle, and shotgun cartridges from the past century and a half.
One of the best features is a 12-page color section depicting actual size drawings of 265 current rimfire/centerfire cartridges and shotshells. You won’t find that many “life-size” cartridge drawings in one place even on the internet. Cartridge profiles and ballistic charts have been expanded to include all new factory cartridges. The authors have even included air rifle pellets and historical images and charts. Softcover, 1008 pages — edited by S.P. Fjestad.
Comments from guys who bought the book:
“This book contains a vast array of information on many modern and even obsolete ammunition. Definitely recommend for any modern reloader novice or experienced.” – Duggaboy460
“It’s a great reference book for individuals who reload their own ammunition. There is a lot more info in this Edition. Everyone who likes this information should have it in their library.” – Reloader
“I like the general and technical comments that are available for each and every cartridge. Information that predicts if a cartridge will stay in production for many more years or rapidly become obsolete.” – RSL1
In this video, Bryan Litz of Applied Ballistics talks about Density Altitude and the effect of atmospheric conditions on bullet flight. Bryan explains why you must accurately account for Density Altitude when figuring long-range trajectories.
Bryan tells us: “One of the important elements in calculating a fire solution for long-range shooting is understanding the effect of atmospherics. Temperature, pressure, and humidity all affect the air density that the bullet’s flying through. You can combine all those effects into one number (value) called ‘Density Altitude’. That means that you just have one number to track instead of three. But, ultimately, what you are doing is that you are describing to your ballistics solver the characteristics of the atmosphere that your bullet’s flying through so that the software can make the necessary adjustments and account for it in its calculations for drop and wind drift.”
Bryan adds: “Once you get past 500 or 600 yards you really need to start paying careful attention to atmospherics and account for them in your ballistic solutions”. You can learn more about Density Altitude in Bryan’s book, Applied Ballistics for Long Range Shooting (Third Edition).
General Scientific Definition of Density Altitude
Density altitude is the altitude relative to the standard atmosphere conditions (ISA) at which the air density would be equal to the indicated air density at the place of observation. Density altitude can be calculated from atmospheric pressure and temperature (assuming dry air). Here is the formula:
Air is more dense at lower elevations primarily because of gravity: “As gravity pulls the air towards the ground, [lower] molecules are subject to the additional weight of all the molecules above. This additional weight means the air pressure is highest at sea level, and diminishes with increases in elevation”.*
Both an increase in temperature, decrease in atmospheric pressure, and, to a much lesser degree, increase in humidity will cause an increase in density altitude. In hot and humid conditions, the density altitude at a particular location may be significantly higher than the true altitude.
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.
22Plinkster Tours CCI/Speer Idaho Factory
Trickshot artist and YouTube host 22Plinkster recently got a chance to tour the CCI/Speer production facility in Lewiston, Idaho. This large plant produces both rimfire and centerfire ammunition. While touring the plant, 22Plinkster was allowed to capture video showing the creation of .22 LR rounds from start to finish. This is a fascinating video, well worth watching.
This revealing video shows all phases of .22 LR ammo production including cupping, drawing, annealing, washing, drying, head-stamping, priming, powder charging, bullet seating, crimping, waxing, inspection, and final packaging. If you’ve got ten minutes to spare, we really recommend you watch the video from start to finish. You’ll definitely learn some new things about rimfire ammo.
.22 Plinkster was literally up to his neck in ammo while touring the CCI/Speer Idaho ammo plant. He says: “This was truly a dream come true for me. I can’t thank the people at CCI and Speer enough for allowing me to do this. I couldn’t possibly show everything that went on at the factory. However, hopefully I showed you enough for you to grasp the concept of how rimfire [ammo] is made.”
Speer Brothers Brought Ammo Production to Lewiston
Here is an interesting historical footnote. Today’s large CCI/Speer operation in Idaho can be traced back to the companies founded by the Speer brothers. After settling in Lewiston in 1944, Vernon Speer started Speer Bullets. A few years later, in 1951, Vernon’s brother Dick (with partner Arvid Nelson) started Cascade Cartridges Inc., a producer of small-arms ammunition and primers. Yes, as you may suspect, Cascade Cartridges Inc. is now CCI, a Vista Outdoor company, and one of the largest manufacturers of primers and loaded ammunition. Today, the CCI/Speer Lewiston plant produces both Speer bullets and CCI-branded ammunition and primers. Vista Outdoor’s predecessor, ATK, acquired the plant in 2001. Vernon Speer died in 1979, and Dick Speer died in 1994.
Chuck’s Pair of Pennsylvania Dashers
There’s been a lot of interest in the 6mm Dasher cartridge lately, so we thought we’d showcase a matched pair of Dasher rifles belonging to a Forum member. The 6mm Dasher began as a wildcat improved version of the 6mmBR Norma cartridge. The 6mm Dasher has been very successful in competition, and now factory Norma-made Dasher cartridge brass is available from Bullets.com.
Forum Member Chuck L. (aka “Ridgeway”) has created a handsome duo of 6mm Dashers for competitive benchrest and varmint matches in Pennsylvania. Both guns are built on Kelbly Panda RBLP actions, with Bartlein 8-twist barrels, and Shehane Laminated Tracker Stocks. However, the two rifles are not exact twins, as you can see. One, which we’ll call the Big Dasher, is built on a Shehane ST1000 Tracker stock. The other gun, the Small Dasher, sports Shehane’s “Baby Tracker” stock — a design used with great success by Richard Schatz. The Big Dasher, optimized for 1000-yard competition, also has a slightly longer freebore — 0.136″ vs. 0.104″ for the Small Dasher.
Specifications for the Dasher Duo:
Small Dasher (13.5-pounder): Chambered for 6mm Dasher with approximately .104 freebore and a .264 NK. (No way of knowing exactly since it freebore was done in a separate operation by Kelbly.) Components are: Shehane Baby Tracker stock, Kelbly Panda RPLB action, Bartlein 1:8″ LV barrel at 26 ¾”, Kelbly Rings, Weaver T36, Jewell trigger. The barrel was chambered by Kelblys and the stock was bedded, glued and balanced by a shooting buddy (Forum Member johara1). I clear-coated the stock with auto urethane. Total weight is 13 lbs., 4 ounces.
Big Dasher (1K Light Gun, 17-pounder): Chambered for 6mm Dasher with a .136 freebore and .264 neck (PTG Reamer). Components are: Shehane ST-1000 stock, Kelbly Panda RPLB action, Bartlein 1:8″ HV 5R barrel at 28″, Shehane +20-MOA rings, Nightforce NXS 12-42x56mm, Jewell trigger. The barrel work, pillar installation, and bedding was done by Dave Bruno. The stock was clear-coated by Chuck with auto urethane. Chuck also made the rear butt plate and balanced the rifle. Total weight: 16 lbs., 13 ounces.
Chuck tells us: “I don’t get out shooting competition as much as I want due to time and family, but when I do compete, I shoot a Groundhog match at Southfork Rifle Club in Beaverdale, PA. Info on Southfork Club events can be found at Southforkrifleclub.com. The Southfork match is basically a 100-, 300- and 500-yard match with one sighter the entire match and 5 shots at each yardage for score. The Small Dasher, with the shorter ‘Baby Tracker’ stock, was set up for the Southfork Rifle Club’s ‘Light Unlimited’ class which has a 13.5-lb max weight.” (Editor: ‘unlimited’ is a misnomer for a weight-limited category.)
Chuck adds: “The Big Dasher with the heavy ST-1000 stock is set up for 1000-yard benchrest matches in Light Gun class. I hope to shoot a couple 1K matches with it at Reade Range in southwest Pennsylvania. I am still in load development for this rifle since it was just finished in January. One ironic thing is, it shoots the same load I’m shooting out of the lighter gun rather well. The only difference between the two chambers is the freebore is roughly thirty thousandths longer on the 1K gun (Large Dasher). I will also shoot this at Southfork in the ‘Heavy Unlimited’ class.”
Dasher Case-Forming: Neck-Turn then Fire-form with Bullets Hard in Lands
To fireform, I turn my cases down to fit the chamber and stop where the false shoulder makes snug contact with the chamber. Fire-forming rounds are loaded up with a 29-grain charge of H4895 or Varget and a 108gr Berger bullet seated hard into the lands about 0.020″ past initial contact with the rifling. It takes about three firings to make a nice clean Dasher case with a sharp shoulder. I anneal about every 3-4 firings. I have many cases that have about 10+ firings on them and they are still shooting well. The primer pockets are a little looser, but still hold a primer.
Both Dashers Group in the Ones at 100 Yards
My main bullet for both rifles is the 107gr Sierra MK, loaded with Reloder 15 powder, Lapua cases and CCI 450 primers. My main load for the Small Dasher is 33.0 grains of Reloder 15. This load shoots in the ones at 100 yards. For the Big Dasher, I’m still working on a load, although the same 33.0 grain load shoots in the ones in the heavier gun as well. I’m still looking for more velocity and my ‘max’ node. So far, I’ve gone well above 33.0 grains of RL 15 without pressure signs, but that load produces vertical at 100 yards, so I’m going to tinker with the load until I see pressure or it starts to shoot.
In this video, Bryan Litz of Applied Ballistics explains how to choose a bullet for long-range shooting and explains what you should be looking for when developing a long-range load. Bryan notes that, with a new rifle build, the bullet you select may actually dictate your gun components. When starting from a “clean slate”, once you select a bullet, you will then pick a barrel, twist rate, and cartridge that are appropriate for that bullet. In choosing a long-range projectile, Bryan recommends you choose a high-BC bullet “that is known for precision”. Then you need to find an ultra-consistent, reliable load.
This video is worth watching. Bryan Litz makes some very good points.
Load Development — Why Consistency is Key (and Half-MOA May Be Good Enough)
After choosing a bullet for your long-range project, then you need to develop a load through testing. Bryan explains: “Once you’ve selected a bullet … and you have selected the components around that bullet, the most important thing to remember in hand-loading is consistency. You’re going to do some testing to see what combination of powder charge, powder type, and seating depth give you the best groups and lowest standard deviations in muzzle velocity.”
Bryan says that if you develop a load that can shoot consistent, half-minute groups in all conditions, you should be satisfied. Bryan says that many long-range shooters “spin their wheels” trying to achieve a quarter-MOA load. Often they give up and start all over with a new bullet, new powder, and even a new cartridge type. That wastes time, money, and energy.
Bryan cautions: “My advice for hand-loaders who are long-range shooters, is this: If you can get a load that is reliable and can shoot consistent, half-minute groups with low MV variation and you can shoot that load in any condition and it will work well, then STICK with THAT LOAD. Then focus on practicing, focus on the fundamentals of marksmanship. The consistency you develop over time by using the same ammunition will mean more to your success in long range shooting than refining a half-minute load down to a quarter-minute load.”
Bryan notes that, at very long range, shooting skills and wind-calling abilities count most: “Your ability to hit a 10″ target at 1000 yards doesn’t improve very much if you can make your rifle group a quarter-minute vs. a half a minute. What’s going to determine your hit percentage on a target like that is how well you can calculate an accurate firing solution and center your group on that target. A lot of people would be more effective if they focused on the fire solution and accurately centering the group on the target [rather than attempting to achieve smaller groups through continuous load development].”
Editor’s Note: We agree 100% with the points Bryan makes in this video. However, for certain disciplines, such as 600-yard benchrest, you WILL need a sub-half-MOA rifle to be competitive at major matches. Well-tuned, modern 600-yard benchrest rigs can shoot 1/4-MOA or better at 100 yards. Thankfully, with the powder, bullets, and barrels available now, 1/4-MOA precision (in good, stable conditions) is achievable with a 17-lb benchgun built by a good smith with premium components.
What happens inside a rifle chamber and barrel when a cartridge fires can’t be seen by the naked eye (unless you are a Super-Hero with X-Ray vision). But now, with the help of 3D-style computer animation, you can see every stage in the process of a rifle round being fired.
In this amazing video, X-Ray-style 3D animation illustrates the primer igniting, the propellant burning, and the bullet moving through the barrel. The video then shows how the bullet spins as it flies along its trajectory. Finally, this animation shows the bullet impacting ballistic gelatin. Watch the bullet mushroom and deform as it creates a “wound channel” in the gelatin. This excellent video was commissioned by Czech ammo-maker Sellier & Bellot to demonstrate its hunting ammunition. The design, 3D rendering, and animation was done by Grafické studio VLADO.
Watch Video – Cartridge Ignition Sequence Starts at 1:45 Time-Mark
Video find by Seb Lambang. We welcome reader submissions.
Forum member Al Nyhus is a top-level score shooter who has competed successfully with the 
