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April 12th, 2019
As the practical/tactical game has evolved, with low recoil and high accuracy becoming ever more important, many top competitors have moved to smaller cartridges such as the 6mm Dasher and its parent, the 6mmBR Norma. These cartridges deliver outstanding accuracy plus good barrel life. However, the “short, fat” 6BR/Dasher design doesn’t feed optimally in magazines designed for the .308 Win family of cases. Yes you can modify your own magazines (Mag Mod HERE), or buy a pricey conversion kit, but now there is a turn-key solution from MDT (Modular Driven Technologies).
MDT’s 6mm BR magazine fits the parent 6mmBR cartridge and all the popular varients including the 6 BRA, 6 Dasher, and 6 BRX. MDT says this new 12-round magazine is a “one-step solution [delivering] smooth, reliable feeding for the most popular rifle cartridges in precision rifle competitions.”
MDT built this AICS-pattern mag for PRS/NRL competitors and anyone wanting to run 6mmBR-family cartridges in mag-fed actions: “The limiting factor for competitors running 6mm BR variants has been feeding. Until now, the only option has been to purchase an AICS-pattern magazine plus an additional kit to make the magazines work with the shorter cartridges. This solution costs upwards of $100 or more and can require additional tuning to work in most rifles.”
The MDT 6mm BR mag has a maximum internal length of 2.580″, which accommodates pretty much any 6mm bullet you’d want to use. These MDT magazines are crafted from quality steel, nitride-treated, then black Cerakote finished inside and out. To reduce friction between cartridge and magazine body, MDT added two internal ribs which provide a smooth transition from double stack to single-feed.
Magazine Conversion — Use .308 Win Mags with Modified Followers
A decade ago we showed our readers how to modify .308 Win magazines to feed the 6mmBR cartridge efficiently. This procedure, explained by Texas gunsmith, Mike Bryant, is easy to do with simple tools. You can modify most standard magazines, both internal-style and detachable style. CLICK HERE for full, step-by-step magazine conversion article.
The basic procedure involves trimming the rear of the magazine, and creating a rear stop with a block from a Remington .223 magazine. Next the .308 Win magazine follower is shortened and beveled. Some guys tweak the feed lips a bit, but this may not be needed. Many of our readers have performed this simple magazine modification and report their rifles feed quite reliably. One reader, who converted a 7mm-08 hunting rig into a 22 Dasher varmint rifle, tells us his modified mag feeds flawlessly.
April 11th, 2019
 
Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.
Chron Testing Lapua Factory Ammo
At our Southern California test range some years ago, we chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.
 Barrel Velocity Variance
Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels.
Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest. (Click Here for results of 6mmBR Barrel Length Velocity Test).
IMPORTANT: Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.
Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.
Factory Ammo Provides a Benchmark
If you have a .223 Rem, 6mmBR, .243 Win, 6.5×47 Lapua, 6.5 Creedmoor, 6.5×55, .308 Win, 30-06, or .338 LM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. [Editor’s NOTE: The original test was conducted in 2008. The velocity of current-production Lapua factory ammo might be higher or lower, so your results may vary.]
When you complete a new 6mmBR rifle, it’s definitely smart to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.
April 11th, 2019
 When shopping for a new riflescope or spotting scope it’s easy to get confused by all the technical terminology. Do you wish you had a better way to compare scopes — beyond just size, weight, and price? Well Swarovski Optik can help. The Swarovski Hunting Blog offers a helpful guide to technical terms used when comparing scope specifications. Here are some important definitions, expressed in layman’s language:
Objective Lens Diameter
The objective lens diameter determines the size of the optical system’s entrance pupil. The bigger the objective lens diameter, the more light the system can capture. However, the size of the objective lens does not determine the size of the field of view.
Exit Pupil
The size of the Exit Pupil is determined by the objective lens diameter and the magnification. If you look at the eyepiece from a distance of around 30 cm (11.8 in), the Exit Pupil appears as a bright disc.
For calculating the Exit Pupil the formula is:
Exit Pupil = objective lens diameter ÷ magnification (expressed in power number).
The larger the Exit Pupil, the more light will reach the eye.
Field of View
The Field of View is the size of the circular section of the area which can be observed when you look through a long-range optical device. In the case of rifle scopes, it is specified at a distance of 100 meters or 100 yards. For example, 42.5 m at 100 m or 127.5″ at 100 yards. As an alternative, the Field of View can also be stated in degrees (e.g. 6.6°).
NOTE: The technically-feasible size for the Field of View is essentially determined by the magnification. The higher the magnification the smaller the Field of View.
Twilight Factor
The Twilight Factor defines the optical system’s performance in poor light. The statement “the greater the twilight factor, the better the suitability for twilight” only applies if the exit pupil is larger than or at least as big as the eye’s pupil. The pupil in the human eye can only open to around 8 mm. As we get older, our eyes become less flexible, which limits our ability to see things in twilight or at night. Therefore [an optic’s] exit pupil cannot always be fully utilized.
For calculating the Twilight Factor the formula is:
Twilight Factor = root of ( magnification x objective lens diameter ).
NOTE: Spotting scopes have extremely high twilight factors because of their high magnification and large objective lens diameter. But [when used at high magnification] their small exit pupil can make them [somewhat difficult] to use in twilight.
CLICK HERE to Read Full Article (with more illustrations).
Photos copyright Swarovski Optik Blog, all rights reserved.
Story Tip by EdLongrange. We welcome reader submissions.
April 7th, 2019
We know our readers like accurate rifles — the more accurate the better. You guys also love really great craftsmanship and state-of-the art componentry. To satisfy that lust for amazing, accurate rifles, we’re starting a new feature — Sunday GunDay. We’ll try to do this a couple Sundays a month, provided we have some great candidates. For our first Sunday GunDay feature, we are presenting a stunning .284 Win F-Open match rifle owned by David Christian of Team Borden/Brux/Lapua. This impressive rig is as good as it gets in the F-Open game. The write-up is by David’s friend, Forum member F-Class John.
Tips For Competitors from David Christian
1. Tracking is Really Important. I learned this lesson from Bill Brown. Make sure your rifle is tracking exactly on your bags. If you slide the gun back and forth and it does not line up on your original aim point, something is out of alignment with you rear bag or mat and needs to be adjusted.
2. Wind Calls — Be Brave. Don’t be timid with your wind calls. It is better to err with a slight over-correction, rather than miss a change entirely.
3. More Data is Good. Keep track of as much data as you can so that you can learn from it. For example I shoot as much as I can with my chrono and track my load speeds so that I can tell if I am drifting out of my node.
David Christian’s .284 Win F-Open Rig
Report by F-Class John
Here’s match rifle that’s as handsome as it is effective (and accurate!). In its first-ever tournament, this impressive rig took 8th place overall in F-Open at the 2019 Berger Southwest Nationals. This .284 Win hammer was wielded by David Christian, the newest member of Team Borden/Brux/Lapua. David built this .284 Winchester around a Borden BRMXD action with black PVD coating and a Jewell BR trigger. What I found fascinating is that David had built all of this before ever being approached for the team. When I asked him how that worked out, he simply said he picked the components he liked the best and knew would do the job. It was just the universe in action that he’s now on the team that matches his gear and he’s certainly not complaining that he gets to represent them now.
David uses a custom-contour 32″-long Brux 1:8.5″-twist barrel that tapers from 1.35” to 1.25” because he likes the extra stability and weight it brings. It’s all mounted in an amazingly-crafted Cerus Stock (Speedy Gonzales “Spear of Destiny” design). While Will McCloskey built the stock, it was finished to perfection by Devin Wiggett and mounted by Terry Wright of Right Rifle in Oregon. You might also notice that the buttstock features a R.A.D. recoil system which adds the final touch to the system.
Stunning Laminated Maple/Cherry/Walnut/Wenge Cerus Stock
When asked what people comment on when they see his gun, David says it’s the stock, hands down. Having handled this gun myself, I have to agree and believe me when I say the pictures don’t do it justice. The exterior forearms are torrified Maple while the core is made up of Brazilian Cherry, Walnut, and African Wenge wood. It makes for an ultra-strong stock with stunning beauty to match.
David currently tops this beauty with a Kahles K1050 10-50x56mm scope featuring the MOAK reticle. David really likes the 20 MOA per revolution dial as well as the top-mounted parallax adjustment. This is especially helpful for him as David shoots left-handed. Most scopes have a left-side parallax knob which is difficult for him to use during a match.
You can’t have a rifle this good-looking and functional without riding on the right gear. David uses a Protektor DR Bag and a SEB Special Edition NEO coaxial front rest. All told it took nearly six months to get all the parts delivered and assembled but he looks at that as a short term loss and a long term gain. Using Erik Cortina’s load development methods with Berger 180gr Hybrid Target or 184gr Hybrid Target bullets and quality Lapua brass, David has achieved some amazing results. Here’s a representative target from a recent match. That’s mighty fine shooting!
If you want to “hit the ground running” in the F-Open game, this wouldn’t be bad setup to emulate and if you see David at a match, he’s always more than happy to talk to you about it.
April 7th, 2019
The Making of MatchKings — How Sierra Produces SMKs
All Sierra bullets begin life as a strip of gilding metal, an alloy consisting of 95% copper and 5% zinc. To meet Sierra’s strict quality requirements, the gilding metal requires three times more dimensional and quality control standards than is considered standard in the copper manufacturing industry.
A blanking press stamps out a uniform disc and forms the cup that will be drawn into the MatchKing jacket. The cup is then polished and sent to a draw press to be drawn into a jacket that is longer than needed for the future MatchKing, thus allowing for the trim process. Press operators constantly check concentricity to make sure we have only quality jackets. The jackets then go to a trimmer where they are visually inspected again.
After being polished a second time, the jacket travels to the bullet press. In the meantime, 80-pound lead billets are being extruded into lead wire for the cores where great care is taken so that the core wire is not stretched. The core wire is lightly oiled before continuing to the bullet press to be swaged.
The lead core wire and trimmed jacket meet at the bullet press where the first stage forms a boattail on the jacket. The lead core is then formed on top of the bullet press and fed down into the jacket. In one stroke of the press, the MatchKing is formed.
Quality control technicians pull samples from each lot of MatchKings to make sure they meet Sierra’s stringent standards. Samples are then sent to Sierra’s 300-meter underground test range (shown below) to be shot for accuracy on mechanical mounts referred to as “unrestricted return to battery rests” that Sierra designed and built in-house.
After inspection, the bullets are placed in the familiar green box along with reloading labels. They are then shrink-wrapped and shipped all over the world.
April 6th, 2019
Here is a very interesting test for the 6 BRA (6mmBR Ackley) cartridge. Forum member James Phillips, a talented long-range benchrest shooter, tested SIX different primer types from three different manufacturers. To help determine vertical dispersion, James set his target out at 500 yards. He then proceeded to shoot 4-shot groups, in order, with each primer type. Velocities were recorded with a chrono. The photo above shows the results. James says: “I’ll retest the best two for accuracy and consistency with 10 shots each”. CLICK HERE for full-screen target photo.
As you can see, ALL the groups are pretty impressive. The smallest groups, 1.253″, was shot with CCI 400 primers. Next best (and very close) was CCI BR4, at 1.275″ for four shots. The “flat line” winner was the Remington 7.5, at upper left. There was almost no vertical. If you are intrigued by this interesting primer test, you can ask join the discussion in this Primer Test FORUM THREAD.
| Primer Brand |
Group Size
| Velocity |
Extreme Spread |
Std Deviation |
| Remington 7.5 |
1.985″ 4 shot
| 2955 FPS |
8 FPS |
4.0 FPS |
| Federal 205M |
2.200″ 4 shot |
2951 FPS |
11 FPS |
4.8 FPS |
| Sellier Bellot SR |
1.673″ 4 shot |
2950 FPS |
14 FPS |
5.9 FPS |
| CCI 450M |
2.341″ 4 shot |
2947 FPS |
14 FPS |
6.6 FPS |
| CCI 400 |
1.253″ 4 shot |
2950 FPS |
3 FPS |
1.3 FPS |
| CCI BR4 |
1.275″ 4 shot |
2949 FPS |
15 FPS |
6.9 FPS |
CARTRIDGE: 6mmBR Ackley, aka 6 BRA. Parent case is 6mmBR Norma. The 6 BRA is fire-formed to create a 40-degree shoulder and less body taper. Capacity is increased, but the neck is longer than a 6mm Dasher. The capacity is enough to get to the 2950+ FPS accuracy node. Some shooters say the 6 BRA is more forgiving than the 6mm Dasher. The 6 BRA is certainly easier to fire-form.
LOAD SPEC: 6 BRA (40° 6 BR Improved), 31.1 grains Hodgdon H4895, Bart’s 105gr “Hammer” bullets.
TEST REPORT — Conditions, Shooting Method, Loading Method
Tester James Phillips posted this report in our Shooters’ Forum:
Conditions: The testing was done in the morning over flags. The flags never moved or even twitched. I had as perfect conditions as I could have asked for. It was overcast so no mirage and no wind. There were no other shooters, just me.
Test Procedure: Each shot was precisely shot at my pace and centered the best possible using my Nightforce 15-55X scope. I did not use the round-robin method. Each four-shot group with the same was shot at one time. Then I moved onto the next primer. Everything felt right for each and every shot fired today. Of course I could repeat the test tomorrow and it could be exact opposite of today’s test. We can chase this forever. But [soon] I’m going to test the BR4 and 400 primer… for best accuracy and consistency for 10 shots each.
How Rounds Were Loaded: Each load was weighed to one (1) kernel of powder. So I know that’s as good as I can weigh them. Each bullet seating force was within 1# on my 21st Century hydraulic arbor press.
Previous Initial Load Testing: All groups were shot with 31.1 grains of H4895. During initial load testing I settled in on the Sellier & Bellot primer to finalize everything as it showed more promise over the CCI 450 Magnum I also tried. I was actually surprised to have seen the higher ES and SD from that primer today along with the vertical shown. [Editor: Look carefully — one shot from the CCI 450 is right in the center black diamond, stretching the vertical. By contrast the Rem 7.5 had almost no vertical.]
Velocity and NODE Considerations: I was about 5-6 FPS above what appeared to been my optimum velocity of 2943-2945 FPS, so I’ll test 5 shots of 31.0 and 5 of 31.1 and see what happens from there. I can only assume my velocities where higher due to the higher humidity and of course temps were 5 degrees warmer this morning as well. It wasn’t far off but I noticed it.
April 6th, 2019
President Donald Trump will address NRA members at the NRA-ILA Leadership Forum on Friday, April 26, 2019 in Indianapolis, Indiana. This is the third consecutive year that President Trump will deliver the keynote address at the Leadership Forum. This is part of the NRA Annual Meetings & Exhibits, which runs April 25-28 at the Indiana Convention Center in Indianapolis.
“Donald Trump is the most enthusiastic supporter of the Second Amendment to occupy the Oval Office in our lifetimes. It is truly an honor to have President Trump address NRA members for the fifth consecutive year,” said Chris Cox, NRA-ILA Executive Director. “President Trump’s Supreme Court [and Appellate Court] appointments ensure that the Second Amendment will be respected for generations to come. Our members are excited to hear him speak and thank him for his support for our Right to Keep and Bear Arms.”
President Donald Trump
Keynote Speaker, NRA-ILA Leadership Forum |
TICKETS HERE: bit.ly/NRAILALeadershipForum |
WHERE:
Indiana Convention Center—Lucas Oil Stadium
100 South Capitol Avenue
Indianapolis, Indiana 46255 |
WHEN:
Friday, April 26, 2019
11:00 am – 4:00 pm
Tickets Required |
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April 3rd, 2019
Vu Pham takes a shot at the Snake River Sportsman Range in Oregon. Click image for full-screen version.
Vu Pham recently attended a great practical/tactical match, the Gem State Stand Off. This NRL-sanctioned match drew 113 shooters, including many of the best PRS/NRL competitors in the country. Vu says this was a great event: “The 220-round, 22-stage course of fire was fun, yet challenging. Every stage had a two-minute par time requiring 10 rounds fired at multiple targets. 113 competitors fired about 24,000 rounds without a single target failure.”
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2019 Idaho Gem State Stand Off AAR
Target Distances: 300 to 1200 yards
22 stages/220 round Course of Fire
113 Competitors
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Match Directors: Nate Lauerman & Seth Howard
Range Officers: 21 Precision Rifle Shooters of Idaho
Event Date: March 23rd & 24th, 2019
Location: Snake River Sportsman Range in Vale, Oregon
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“With technological advances in equipment, training, and ballistics, plus increased opportunities for competitors to fine-tune their skills, Practical Precision Rifle competition has become a perfectionist sport. The constant evolution of this discipline never ceases to amaze me. With competitors and manufacturers constantly pushing to gain an edge… there is no shortage of innovation.” — Vu Pham
Gem State Stand Off — After Action Report
Report by Vu Pham, NorCal Practical Precision Rifle Club
I was fortunate enough to snag a last-minute slot for the 2019 Gem State Stand Off hosted by the Precision Rifle Shooters of Idaho Club (PRSID). This is one of 17 National Rifle League events where competitors will battle for points hoping to secure a slot for the 2019 NRL Championship. The Snake River Sportsman Range is a beautiful venue in Vale, Oregon, near the Idaho border.
The digital display carries ballistics info and elevation/windage tables from Vu Pham’s Kestrel. He says the unit really helps his performance.
From the hills looking down-range. Click image for full-screen version.
Hardware Report — Top PRS/NRL Gear for 2019
Modern Precision Rifle Comp Gear — Stocks and Chassis Systems
The traditional rifle stock we know has now moved to more modular and customizable designs. One product that caught my eye is the new XLR Industries Envy JV Heavy Fill Chassis system. After seeing a lot of competitors use them with good results, I think I will be giving one a try soon. Not being able to borrow a piece of gear because the entire squad is running ARCA can be a drag. Picatinny forearm rails have gone the way of the dinosaur with ARCA Swiss becoming the standard for attaching accessories.
Those like myself who may not want to give up their traditional-style stocks do have the option of modifying their existing stock with a universal ARCA rail from Henderson Precision. That company makes a variety of rails that fit a number of stock platforms.
Rifle Support Options — Bags and Tripods
Tripods are also used a lot as front and rear support by the majority of the field as well. Support bags now come in every shape, size, weight, and material imaginable. Even the fundamentals of driving your rifle is being challenged by the evolution of “free recoil”. Instead of counting the number of hits for the day, the top echelon shooters count the number of shots they dropped.
Calibers of Choice — Small is Big — the 6mms Dominate
6mmBR Improved cartridges (6mm Dasher, 6BR Ackley) and mid-sized 6mms (such as 6mm Creedmoor) dominate the field. In addition we are seeing some guys running the 22 BR and 22 BRA, which work surprisingly well. [Editor: Run the ballistics with a .22 Cal 80-grainer and you’ll see why.]
Wind Monitoring and Ballistics
Kestrel Environmental Meters with Applied Ballistics are “must haves”. I have found my Really Right Stuff tripod and Vortex 12×50 Razor binoculars extremely useful for locating targets and going through the target shooting order before it was my turn to shoot. Watching what the wind and competitor’s rounds are doing before you are on the gun is a huge benefit.
Great Match with Great Shooters
Tough Competition with a Field of Ace Practical Marksmen
The field of competitors at this match was stacked. I heard there were 20 competitors in attendance who have won national-level PRS or NRL events. 20 top-echelon competitors mixed in with a solid field of shooters made it a tough for anyone looking to finish at the top.
March 29th, 2019
Close-up view of a sectioned case. This one here was “fixin’ to pop”, says Glen Zediker.
Here are highlights from an article Glen Zediker wrote for the Midsouth Blog. In this article Glen focuses on cartridge brass. Glen discusses the most common failures that appear with brass that has been shot multiple times, or which has been fired at excessive pressures. Glen explains some simple ways to check your cartridge brass to detect “early warning signs” of case failure, particularly case head separation, which can be dangerous.
Glen is the author of many excellent books on reloading. This article is adapted from Glen’s books, Handloading For Competition and Top-Grade Ammo, available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com.
How Cases Degrade with Multiple Firings By Glen Zediker
This article explains when, and then how, to check after the progress of changes commencing with the firing on a new case. It’s the “progress of degeneration,” in a way of looking at it because the concern is getting a handle on when enough change in the brass has come about to require attention. Or abandonment. As said then, for me that’s 4 firings. That, as said last time, is when I might see changes that need attention. Also as said, that figure didn’t come out of a hat, but from my own notes in running my competition NRA High Power Rifle loads. [Editor’s Note: With Lapua brass, using moderate loads, in bolt-action rifles, we typically get about 10 good (match-worthy) firings. But if you anneal your Lapua brass, and run modest pressures, Lapua brass can perform well for 20 or more load cycles.]
The areas most affected are the case neck and case head area. Case neck walls get thicker [but] the case head area body walls get thinner. Primer pockets get shallower and larger diameter.
This case shows a cracked neck AND a crack (separation) above the case head. Zediker says it is “rare to see one case with both of the most common failures. [This case] was attacked by an M14.”
Case Head — Causes of Separation and Cracking
When a case is under pressure during firing, the brass, like water, flows where it can, where it’s more free to move. Of course, the chamber steel limits the amount it can expand. The case shoulder blows fully forward and the case base is slammed back against the bolt face. There is, therefore and in effect, a tug on both ends — it gets stretched. The shoulder area is relatively free to expand to conform to the chamber, but the other end, the case head area, is not. Since that’s the area of the case with the thickest walls, it doesn’t expand “out” much at all. What it does is stretch. The “case head area,” as I refer to it here, is the portion of the case above the web, which is just above the taper that leads in to the extractor groove. The “area” extends approximately an eighth-inch up the case body.
Here’s a “pressure ring.” You’ll see this after firing, if you see it. And, if you see it, that case is done. The bright ring indicates excessive stretching, which indicates excessive thinning. If you see a ring circling the case, noticeable because it’s lighter color than the case body, and it’s in this area, I’d say that case is done. And that’s right where a “head separation” occurs. It can crack and also blow slap in two, and that’s the “separation” part of case head separation.
Photo courtesy GS Arizona.
This is a spot to keep close watch on as cases age. It is also the area that is more “protected” by sizing with less case shoulder set-back. That is, pretty much, where the freedom for the stretching movement in this area comes from (the case shoulder creates a gap). If you’re seeing a sign that a head separation [might happen with relatively few firings], chances are the shoulder set-back is excessive, and also… the load pressure level.
Bent Paper Clip Case-Wall Gauge
Editor: You can use a bent paper clip to detect potential case wall problems. Slide the paper clip inside your case to check for thin spots. GS Arizona explains: “This simple little tool (bent paper clip) will let you check the inside of cases before you reload them. The thin spot will be immediately apparent as you run the clip up the inside of the case. If you’re seeing a shiny line on the outside and the clip is really hitting a thin spot inside, it’s time to retire the case.” Photo by GS Arizona.
Monitor Primer Pocket Dimensional Changes
Another case-head-area and pressure-related check is the primer pocket. As said, the primer pocket will get larger in diameter and shallower in depth each firing. As with many such things, the questions are “when” and “how much,” and the main thing, “how much?”
If the pocket gets excessively shallow, and that’s judged by a primer that seats fully but isn’t at least a tick below flush with the case base, there could be function issues. There’s a risk of a “slam-fire” with a semi-auto that uses a floating firing pin, and, if there is actual protrusion, that has the same effect as insufficient headspace. A primer pocket uniformer can reset the depth of a shallowed primer pocket to what it should be, but the real test for me is how easily the next primer seats into it. If it’s significantly less resistance, I’ll say that case is done. Shallower can be refurbished. That’s a primary function of a primer pocket uniformer. Larger diameter, though, can’t be fixed. I’ve mentioned in another article or two that, any more at least, my main gauge of load pressure has become how much primer pocket expansion there’s been.
 Glen’s books, Handloading For Competition and Top-Grade Ammo, are available at Midsouth HERE. For more information about other books by Glen, visit ZedikerPublishing.com
Glen’s newest book, America’s Gun: The Practical AR15. Check it out HERE!
March 28th, 2019
The milestone 40th Edition of the Blue Book of Gun Values is releasing April 1, 2019. Purchase this popular price guide through Blue Book Publications for $49.95. Or save $7.58 by ordering from Amazon for $42.37. The Blue Book of Gun Values by S.P. Fjestad is the leading gun valuation resource. There are now over 1.8 million copies in circulation worldwide. This book continues to be the “Bible” for buyers, sellers, collectors, and connoisseurs in the firearms industry. NOTE: For the first time in decades the value of many collectible firearms have gone down significantly — the new 40th Edition carefully tracks this recent trend.
Blue Book of Gun Values, 40th Edition, April 2019
The 40th Edition contains new-for-2019 firearms makes and models, with important pricing updates on many current and discontinued models.
2,512 pages are included on nearly 1,700 manufacturers/trademarks, with almost 23,000 gun model descriptions, and over 500,000 values!
Review by Tom Gresham, Gun Talk Radio Host
“At some point, every gun owner asks the question, ‘What’s it worth?’ The leading reference for decades has been the Blue Book of Gun Values. Whether you are a seller, a buyer, a shopper, or just curious, this constantly-updated gold mine of research is your friend.”
Online Subscription Options
You can also access all the latest Blue Book gun pricing info via an Online Subscription. You can purchase a One-year subscription for $34.95, or you can get a monthly subscription, billed $3.95 per month recurring. For general subscription information, visit the Blue Blue Online Subscription Page.
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Features of the new Blue Book of Gun Values:
· 2019 makes and models are included, with many new handguns and rifles.
· 2,512 Pages covering nearly 1,700 manufacturers and trademarks, with almost 23,000 gun model descriptions.
· 500,000+ up-to-date values are provided. No other book has more.
· Important pricing updates on major trademark current, antique, and discontinued models, including Colt, Winchester, Smith & Wesson, and Ruger.
· An 80-page color Photo Percentage Grading System (PPGS) which makes firearms grading even easier and more accurate.
· More information, more values, more illustrations, and more history than any other gun price guide on the market.
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Sample Page from Blue Book of Gun Values:
Book tip from EdLongrange. We welcome reader submissions.
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