German Salazar, a top small-bore and centerfire shooter, uses the 6XC cartridge in some long-range matches. German has tried a variety of different types of brass for this cartridge, including necked-up 22-250 brass and Norma 6XC brass from David Tubb’s (Superior Shooting Systems). German’s measurements reveal significant differences in water capacity, as well as neck-wall thickness.
6XC Source Brass Dimensions
Case Capacity and Pressure Issues
German has noted significant variances in capacity among the different “flavors” of brass. Norma-headstamp 6XC brass has 49.3 grains of H20 capacity, while Norma 22-250 brass holds only 47.8 grains of H20. Third-generation Tubb-brand 6XC brass is somewhere in the middle, with 48.6 grains of capacity. German did not have a chance to measure the high-quality Lapua 22-250 brass introduced in 2010. NOTE: These differences in case capacity are large enough that you MUST adjust your load to the brass type.
We ran a 6XC QuickLOAD simulation with 115gr bullets and H4350 powder. QuickLOAD predicted that the observed difference in case capacity can result in pressure differentials as much as 4,500 psi! In other words, if you switch from Norma 6XC brass to a lesser-capacity brass type, your pressures could rise 4,500 psi (using H4350 and 115gr bullets).
We recommend sticking with the Norma 6XC brass. It is available from DavidTubb.com for a reasonable $69.00 per 100 cases. These days, that’s cheaper than many other types of premium imported cartridge brass.
Neck Thickness and Chambering Issues
German noted that the different types of available brass varied quite a bit in neck-wall thickness — from 0.0121″ (Norma 22-250) to 0.0140″ (Tubb 3rd Gen). Consequently the diameter of loaded rounds also varied. Depending on the brass you chose, your loaded rounds could be 0.267″ at the neck or 0.271″ (with no-turn brass). That’s a huge difference and it’s something you need to take into account when you have your chamber cut for a barrel. For a cross-the-course rifle, you might want a chamber with at least .003″ total clearance over a loaded round. Obviously, to achieve that clearance, you’ll need to set chamber dimensions base on your preferred type of brass.
NOTE: The research for this story was conducted in 2010. Dimensions may have changed with more recent production, so you should double-check the case capacity of your own 22-250 or 6XC brass.
Sam Hall is a multi-time IBS 600-yard Shooter of the Year, who holds many IBS mid-range records. It’s tough to beat Sam when he’s on his game. But it looks like Sam may have a worthy challenger in a few more years. Sam’s 6-year-old son Hunter Hall has already showed an interest in his father’s shooting hobby. It turns out Hunter has the God-given talent for hitting the target. There could be another champion in the Hall family someday….
Like Father, Like Son…
Sam told us: “Future Shooter? I wanted to share this with everyone. My son Hunter has taken interest in what I do. Above he is pictured shooting my competition rifle, which had just received a new barrel chambered in 6 BRDX. Hunter helped me get zeroed.”
Sam explained: “This weekend we practiced freehand shooting with his BB gun at cans and then did some archery practice. After that I was needing to zero my Light Gun and get started with a few loads at 100 yards. To my amazement my 6-year-old wanted to accompany me. I could not believe it when he wanted to shoot my competition rifle. I had just put a new barrel and scope on it and needed to zero it. After two shots to get it zeroed he hit a .25 inch dot at 100 yards. I let him do everything from loading it, ejecting rounds and even working my Farley joystick rest.
By the way, this 6 BRDX gun looks like it’s going to shoot and my boy did great operating and shooting the rifle and Farley rest! It won’t be long before he is going with me to competition. Look out, he is more coordinated and athletic than his Daddy.” — Samuel Hall
Successful long-range shooters know that careful weighing of powder charges helps them achieve superior long-range accuracy. By maintaining powder charges within very narrow weight tolerances, hand-loaders can produce ammo with more consistent muzzle velocities from shot to shot. Low Extreme Spread (ES) and Standard Deviation (SD) numbers translate directly to reduced vertical dispersion at very long ranges (although velocity is not the only contributing factor to vertical spread). In pursuit of load weight uniformity, many of our top long-range aces have invested in the latest, high-tech magnetic force restoration (MFR) digital scales (such as the Sartorius GD503). These laboratory-grade MFR scales are extremely stable (with minimal drift) and they can reliably measure to .005 grain, that is five thousandths of a grain. That is less than the weight of one kernel of typical extruded powder. For example, with Varget, there are three to four kernels in one-tenth of one grain of Varget. That means each kernel weighs .025 to .035 grains.
With the capability of modern modern MFR scales to measure less than one-hundreth of a grain, we have a new frontier in precision reloading. You’ll note, in the preceding paragraph, we said that one-tenth of one grain of Varget is three or four kernels. Well, “which is it?” you might ask. The answer is that it might be three, or it might be four, depending on the size of the individual kernels. That’s a disturbing uncertainty that we simply had to accept… until now.
Powder Kernel Uniforming — A Breakthrough
We now have the tools and the methodology to resolve the inherent uncertainty in individual kernel weight. Using the new technique of powder kernel uniforming, first pioneered by German Salazar, we can now, for the first time, ensure that every kernel of powder that goes into a cartridge is virtually the same weight — the same, in fact, within 0.01 grain (one-hundredth of a grain) TOTAL spread.
For a reloader looking to achieve “perfect” load weight uniformity, powder kernel uniforming offers the ultimate control over powder weight. The method we devised to uniform individual kernels consists of kernel core-drilling. The propellant we chose for this kernel-uniforming test was a new prototype (not yet commercially available) EuroChemie RL “X” propellant. This was chosen because it offered relatively large, can-shaped kernels that could be drilled relatively easily.
Core-Drilling Kernels with Micro Drill-Bits
The center of each kernel was bored out with a micro-drill. But here’s the key. Before drilling, we first weighed each kernel. Then we selected a micro drill bit of appropriate diameter to achieve uniform weights. With the heavier kernels (in the 0.04 gr range) we used a larger micro-bit. With the lighter kernels (in the 0.02 range), we selected a smaller diameter micro-bit that removed less material from the center of the kernel. Obviously, many kernels were ruined while we perfected the drilling process. It required great patience and a very steady hand. But after a few dozen hours of drilling, we had a batch of uniformed kernels that were all within plus or minus .005 grains (.01 grain ES). Now we were ready to do some testing.
Proof That It Works
All this time-consuming work to drill holes in individual kernels would be pointless, of course, if it did not produce meaningful accuracy gains. The proof, as they say, is “on the target”. We were curious to see if our uniformed powder kernels would out-perform unmodified kernels, so we did some field testing. We prepared two batches of 6mmBR ammo in Lapua brass, with full case prep, and bullet base to ogive sorting (we wanted to eliminate as many variables as possible). Bullets were Lapua 105gr Scenar Ls, which proved to be some of the most consistent projectiles we’ve ever measured.
One set of rounds was loaded with a carefully-weighed charge of unmodified kernels. Case to case charge weight was held to .05 grain (half a tenth uniformity). Then we prepared a second batch of cartridges with uniformed kernels, using the exact same charge weight, also held to .05 grain (half a tenth) tolerances. We took these rounds to the range, and did a “round-robin” test at 800 yards, shooting one of each type in sequence (i.e. one uniformed on right, then one non-uniformed on left) until we had two 10-round groups. The test was done with a rail gun fitted with a 1:8″ twist, 28″ Krieger 0.236″ land barrel. The uniformed-kernel ammo was shot at the right diamond, while the non-uniformed rounds were shot at the left diamond. Conditions were good, so we simply “held center” on every shot. No attempt was made to correct for wind as our primary concern was vertical dispersion.
Ammo with Uniformed Kernels Shows Significantly Less Vertical Dispersion at Long Range
As you can see, the uniformed-kernel ammo out-performed the non-uniformed ammo. The difference is quite clear. The rounds with non-uniformed kernels (on the left) produced a 10-shot group with roughly 3.0 inches of vertical dispersion. On the right, our ammo with uniformed kernels produced a group with 9 of 10 shots showing roughly 1.75 inches of vertical dispersion (we did have one high flier among the uniformed-kernel rounds). Additionally, we had a lower 10-shot ES and SD with the uniformed-kernel ammo. We repeated this test two more times and the results were similar. The targets speak for themselves. If you are looking for ultimate long-range accuracy, powder kernel uniforming is a “new frontier” you may wish to explore. With all other factors held constant, we were able to reduce vertical dispersion by more than an inch at 800 yards by drill-uniforming our NitroChemie powder. That’s huge in the long-range game.
Yes, the kernel-uniforming process is incredibly time-consuming and tedious, and a set of micro-drills is not cheap. We also freely acknowledge that the process may be much less productive with narrow-kernel propellants that are hard to drill. (Also EuroChemie powders are preferred because the burn rate controlling compounds are impregnated throughout the entire kernel — not just the outside.) But the potential for significant accuracy gains is there. We proved that.
Is it worth the huge investment of time to drill your powder kernels? That’s a question each reader must ask himself. But if you know the competitor on the next bench over has uniformed his kernels, can you afford not to do the same? Sometimes the extra effort is worth it, just for the peace of mind you get knowing you’ve done everything possible to achieve “ultimate accuracy”.
Next time you have a barrel fitted, consider having your gunsmith create a “stub gauge” from a left-over piece of barrel steel (ideally taken from your new barrel blank). The outside diameter isn’t important — the key thing is that the stub gauge is created with the same reamer used to chamber your current barrel, and the stub must have the same bore diameter, with the same land/groove configuration, as the barrel on your rifle. When properly made, a stub gauge gives you an accurate three-dimensional model of the upper section of your chamber and throat. This comes in handy when you need to bump your case shoulders. Just slide a fired case (with spent primer removed) in the stub gauge and measure from base of case to the end of the gauge. Then, after bumping, re-measure to confirm how much you’ve moved the shoulder.
In addition, the stub gauge lets you measure the original length to lands and freebore when your barrel was new. This gives you a baseline to accurately assess how far your throat erodes with use. Of course, as the throat wears, to get true length-to-lands dimension, you need take your measurement using your actual barrel. The barrel stub gauge helps you set the initial bullet seating depth. Seating depth is then adjusted accordingly, based on observed throat erosion, or your preferred seating depth.
Forum member RussT explains: “My gunsmith [makes a stub gauge] for me on every barrel now. I order a barrel an inch longer and that gives him enough material when he cuts off the end to give me a nice case gauge. Though I don’t have him cut that nice-looking window in the side (as shown in photos). That’s a neat option. You can tell how much throat erosion you are getting from when it was new as well. For measuring initial seating depths, this is the most useful item on my loading bench next to calipers. Everyone should have a case gauge made by there smith if you have a new barrel put on.”
Forum member Lawrence H. has stub gauges made with his chamber reamers for each new barrel. He has his smith cut a port in the stub steel so Lawrence can actually see how the bullet engages the rifling in a newly-cut chamber. With this “view port”, one can also see how the case-neck fits in the chamber. Lawrence tells us: “My stub gauges are made from my barrels and cut with my chamber reamers. With them I can measure where my bullets are ‘touching the lands’ and shoulder bump dimensions. This is a very simple tool that provides accurate information.” To learn more about stub gauges, read this Forum Thread. The photos above and below show Lawrence’s stub gauges:
American Rifleman Magazine is now available in a web-friendly online version. The eZine version of American Rifleman navigates like a conventional print magazine — so you start with an index at the front and you can flip pages from front-to-back. You can also navigate with thumbnails (on the left) and zoom in and out if you find items of interest. Those who prefer reading articles in a magazine-style format should enjoy the American Rifleman digital eZine.
Excellent Article about Norma
In the lastest April digital edition of American Rifleman (on page 122), you’ll find “A Century of Bullets and Brass”, a fascinating 20-page history of the Norma company. Founded by the Enger brothers from Norway, Norma started producing boat-tail 6.5mm bullets in 1902. Using once-fired brass, Norma began loading 6.5×55 ammunition in 1914, and the company started making its own Norma-headstamp cartridge brass in 1917.
Other highlights of the April 2012 edition include:
Interviews with Top Shot Winners Dustin Ellermann and Chris Reed (p.144).
Review of the new Sig Sauer 224 compact pistol by Field Editor Wiley Clapp (p. 94).
Discussion of the “Castle Doctrine” which allows citizens to defend home and family (p. 30).
Previews of new Guns, Optics, and Gear at NRA Annual Meetings and Exhibits in St. Louis.
Here’s good news for .221 Fireball and 20 Vartarg Fans — within the next five to eight weeks, Nosler-brand .221 Fireball brass will hit the market. We just got off the phone with Nosler, whose representatives confirmed that Nosler will be selling 100-ct boxes of .221 Rem Fireball brass very soon (item #10078). Product is expected to start shipping “in a month or two”. Nosler’s .221 Fireball brass is crafted by a third-party supplier, and then final-finished by Nosler at its Bend, Oregon factory.
We tried to find out the name of the third-party source without success. However, Nosler did confirm that this brass “is definitely NOT made by Remington“.
Expected retail for the Nosler .221 Fireball brass is $60.00 to $80.00. Online retailer Precision Reloading currently has the Nosler-brand .221 Fireball brass on order, with a stated retail price of $69.39 for a 100-ct box, product # NS10078. You’ll find the Nosler .221 Fireball brass on the Precision Reloading website, but it is currently listed as “out of stock”. Check back in a few weeks to see if the Nosler .221 Fireball brass has started shipping yet. NOTE: In addition to the new .221 Fireball offering, Nosler has announced that it will sell brass in three other new calibers: 17 Remington, .222 Rem, and 270 WSM.
As soon as its new .221 Fireball brass becomes available, Nosler has promised to send us samples. We want to see how the Nosler brass compares to Remington-brand .221 Fireball brass — currently the only type on dealers’ shelves. With Nosler’s reputation for quality, we hope the Nosler .221 Fireball brass will be a step up from Remington’s product. The Remington brass does the job but case weights and neckwall thicknesses are not particularly uniform, and the Rem brass is fairly soft.
For years, many shooters have coated bullets with Moly (molybdenum disulfide) or Danzac (tungsten disulfide or “WS2″). The idea was to reduce friction between bullets and barrel. In theory, this could lengthen barrel life and extend the number of rounds a shooter can fire between cleanings.
Moly and WS2 both have their fans, but in the last couple of years, some guys have switched to Hexagonal Boron Nitride (HBN), another dry lubricant. The advantage of HBN is that it won’t combine with moisture to create harmful acids. HBN is very slippery and it goes on clear, so it doesn’t leave a dirty mess on your hands or loading bench. Typically, HBN is applied via impact plating (tumbling), just as with Moly.
HBN Results — Both on Bullets and Barrel Bores
Many folks have asked, “Does Hexagonal Boron Nitride really work?” You’ll find answers to that and many other questions on gunsmith Stan Ware’s popular Bench-Talk.com Blog. There Paul Becigneul (aka Pbike) gives a detailed run-down on HBN use, comparing it to other friction-reducers. Paul also discusses the use of HBN in suspension to pre-coat the inside of barrels. Paul observes:
We coated our bullets … how we had been coating with WS2. Now our bullets have a slightly white sheen to them with kind of like a pearl coat. They are so slippery it takes a little practice to pick them up and not drop them on the trailer floor. What have we noticed down range? Nothing different from WS2 other than the black ring on your target around the bullet hole is now white or nonexistent. Our barrels clean just as clean as with WS2. Your hands aren’t black at the end of the day of shooting and that might be the most important part.
Interestingly, Becigneul decided to try a solution of HBN in alcohol, to pre-coat the inside of barrels. Paul had previously used a compound called Penephite to coat the inside of his barrels after cleaning. Paul explains:
If Penephite was used because it was slippery wouldn’t HBN be better? … We called Jon Leist again, and talked to him about mixing HBN and 90% alcohol for a suspension agent to pre-lube our barrels. He though it sounded great but that the AC6111 Grade HBN would be better for this use. It would stand up in the alcohol suspension and cling to the barrel when passed through on a patch. We got some from Jonn and mixed it in alcohol 90%. We use about one teaspoon in 16 ounces of alcohol.
We started using it this fall and what we have noticed is that now that first shot fired out of a clean and pre-lubed barrel can be trusted as the true impact point. We use tuners so now I got to the line, fire two shots judge my group for vertical, adjust the tuner as needed or not, and after tune has been achieved go to my record targets. This use has saved us in time at the bench and bullets in the backstop.
You really should read the whole article by Becigneul. He discusses the use of barrel lubes such as Penephite and “Lock-Ease” in some detail. Paul also provides links to HBN vendors and to the Material Safety Data Sheets (MSDS) for the various compounds he tested.
For many cartridge types, Hornady Superformance ammunition provides enhanced velocity compared to some other types of factory-loaded ammo. However, Hornady has found that there may be issues when Superformance ammo is shot in gas-operated guns with barrels under 20″, or with barrels fitted with suppressors. This is because the gas returning from the barrel port may cause the bolt to begin unlocking prematurely. Hornady has published the following information concerning the uses of Superformance ammo in direct impingment and gas piston self-loading rifles.
Internal Ballistics of Superformance Ammo in Semi-Auto Guns
Superformance™ ammunition is tested and is safely within SAAMI pressure guidelines. Gas operated (direct impingement or gas piston) firearms are perfectly safe to use with Superformance ammunition. However, Hornady ballisticians have conducted testing with a variety of guns (including guns equipped with suppressors), and our findings conclude that some systems work far better with Superformance ammunition than others.
It is recommended that to get the best functioning with Superformance ammunition in gas operated/gas piston semi-automatic or select fire guns, rifle length gas systems with 20 inch or longer barrel lengths are best for reliable firing and extraction. Any other configuration — particularly shorter barrels/gas systems — are best served with the installation of an adjustable gas system, ESPECIALLY if a suppressor is to be installed.
Due to the longer duration of peak pressure produced by Superformance, the post peak/declining port pressure at common carbine and mid-length gas port locations is still higher than that produced by standard propellant. This has a tendency to flood the system with a larger volume of gas, at a higher velocity, that tries to open the bolt of the gun too fast. It’s a timing issue. The cartridge case is still swollen from the application of pressure during firing while the gun is simultaneously trying to extract the cartridge case before it has had an opportunity to settle back to its original size, or more simply: the gun is still in the process or firing while it’s trying to extract the cartridge case.
If the firearm and the ammunition are not in sync, there can be what is commonly identified as “pressure signs” on the cartridge case. This is exhibited by the movement/marring of the head of the cartridge case, cratered primers, flat primers, ripped or ruptured cartridge cases, “popped primers”, and/or any combination of these effects. If any of these “pressure signs”; are apparent, stop firing immediately. If an adjustable gas system is installed, it is advisable to reduce the amount of gas flowing through the system by closing the gas port until the gun operates correctly.
With the installation of an adjustable gas system, gas pressure can be metered to a point that enough gas is applied to open the bolt, but at a slower rate to allow the cartridge case to return to its original diameter prior to the movement of the bolt, and thus allow for proper extraction.
Pressure VS Gas Port Location
Due to the longer duration of peak pressure produced by Superformance™, the post peak/declining pressure at common carbine and mid-length gas port locations is still higher than that produced by standard propellant. However, there is very little difference in port pressure between Superformance™ and standard propellants at the rifle length port location.
Superformance and Suppressors
The use of suppressors on rifles creates yet another dynamic in firearms design that is not commonly understood or communicated. Consider the suppressor on a firearm the same as a muffler on a car. The suppressor works as a filter for the gas (noise) that is escaping the barrel during firing. As a “filter”, it takes longer for the gas to leave the confines of the firearm, and thus, it creates back pressure. This back pressure, ESPECIALLY in a gas operated firearm forces an extensive amount of gas back through the firearm’s operating system that may create too much thrust too early during the firearm’s cycle of operation.
To counteract this back pressure, the use of an adjustable gas system is advised. By metering the gas system to ensure that it will cycle the firearm correctly and not flood the system with gas/pressure, the gun will work properly and will still benefit dramatically from the increased velocity potential of Superformance ammunition.
The days of the “ORM-D: Small Arms Cartridges” labels for ammo shipments are numbered. The Dept. of Transportation (DOT) is phasing out the current ORM-D ammo labels, replacing them with a larger striped diamond label that does not mention “Small Arms Cartridges”. This change is designed to harmonize U.S. shipping rules with United Nations standards. You can start using the new “Limited Quantity” diamond labels for ammo shipments immediately, but they are not mandatory — yet. You can continue to use the old ORM-D “Cartridges, Small Arms” labels until December 31, 2013. As of January 1, 2014 you MUST use the Striped Diamonds.
OFFICIAL UPS RULES — Elimination of ORM-D Classification In an attempt to harmonize and align with international standards, the DOT has amended the 49CFR regulations regarding the ORM-D classification. Effective January 19, 2011, with the publication of the HM-215K final rule, the hazard class of ORM-D is being eliminated. Those materials may still be shipped classified as a limited quantity (“Ltd Qty”). In conjunction with ORM-D hazard class elimination in HM-215K, limited quantity ground shipments will no longer require shipping papers when prepared under the new rule. This includes those materials previously classed as Ltd Qty that required shipping papers via ground transport.
Ground Ltd Qty Marking
Air Ltd Qty Marking
NOTE: These illustrations are not true to scale. The actual default Ltd Qty Diamond label to be used for ammo shipments is much larger, about 5″ per side. A smaller 2″ per side version of the Ltd Qty striped diamond can be used on smaller packages.
There is a transition period for shippers to comply with the new classification, marking and labeling requirements. Until December 31, 2013 a limited quantity package containing a consumer commodity as defined in 171.8 may be reclassed as ORM-D, or until December 31, 2012 for ORM-D-Air material. UPS began accepting materials with the new markings effective April 1, 2011. Note: To be in compliance with TDG, Standard (ground) Ltd Qty shipments to Canada prepared under HM-215K require the verbiage ‘Limited quantity’ or ‘Ltd qty’ to also be marked on the carton.
Download OLD and NEW Label Formats
On the Parallax Curio and Relic Forum, a thread includes PDF samples of both the new Diamond Ltd Qty Labels and the current ORM-D Labels. The thread explains: “The good news is the new label doesn’t have any indicator that the package contains ammunition. The bad news is the new label is gigantic compared to the old ORM-D label. You are required to use one of the larger labels on one side of any package containing ammunition. If the package is too small for one of the larger labels then you are permitted to use one of the smaller labels instead. Because of the size requirement in the regulations, you only get two of each label on standard piece of printer paper.”
If you want to still use the ORM-D Small Arm Cartridges Labels until the new Diamond Labels are mandatory, here are links to PDF sheets of ORM-D labels. These PDFs have many rows of labels per page so you can save printer paper. The black version and blue version will use up more printer ink, so you might want to use the white version to be more economical.
With the price of premium brass topping $90/100 for many popular cartridges, it makes sense to consider annealing your brass to extend its useful life. Forum member Darrell Jones offers a full range of brass prep, brass forming, and brass restoration (annealing, ultra-sonic cleaning) at very affordable prices. Starting at just $15 per 100 cases, Darrell’s company, DJ’s Brass, will anneal your used brass using state-of-the-art Bench-Source annealing machines. He can also ultrasonically clean cases for $15 per 100 ($20 per 100 for magnum cases larger than 0.473″ rim).
Custom Neck-Turning Services
Another great service DJ’s Brass provides is precision neck-turning. He can neck-turn any size case to your specified neck-wall thickness. The price is $0.30 per case (normal size) or $0.40 (magnum size) with a $20.00 minimum order. And if you’ve got a bucket of brass to neck-turn, that’s fine with Darrell — he recently neck-turned 1500 pieces of brass for one customer!
DJ’s Brass can process everything from .17 Fireball all the way up to the big magnum cases. And the job gets done quickly. Darrell has a 10-day turn-around guarantee. For most jobs, Darrell tells us, he gets the processed brass to the Post Office within three business days. DJ’s Brass charges only actual shipping fees, using USPS flat-rate boxes.
• Ultrasonic Cleaning + Annealing ($25.00/100 normal or $30/100 magnum)
• Ultrasonic Cleaning and Polishing ($15.00/100 normal or $20/100 magnum)
• Anneal Case Necks (after checking for splits) ($15.00/100 normal or $20/100 magnum)
• COAL Trim and Chamfer Case Mouths ($0.20 per case, $20.00 minimum order)
• Uniform and Square Primer Pockets ($0.15 per case, $20.00 minimum order)
• Expand Case Necks and Anneal brass (Call for Price)
• Create False Shoulder for Fire-Forming (Call for Price)
Muzzle Brake Tax Break Special: FREE cleaning of up to two (2) Stainless Muzzle Brakes with a minimum $50.00 order. Special good through April 17, 2012 (Tax Return Deadline for 2012).
DJ’s Brass Offers Specialized Custom Services
Darrell tells us: “At DJ’s Brass, we can handle all your brass refurbishing needs. From ultrasonic cleaning to custom annealing for specific wildcat cartridges. We can expand your necks from .22 caliber to .30 caliber and anneal shoulders for consistent bump-back. We can turn your case-necks and trim the brass to your specs. For some cartridge types, I can pre-form cases to assist in fire-forming a wildcat cartridge. We also remove the carbon build-up in muzzle brakes. Don’t lose your accuracy by having carbon build up and close off the clearance required for the most accurate bullet release through a muzzle brake.” Note: Extra charges apply for neck-turning and neck expansion operations, or specialized cartridge-forming operations. Please call 205-461-4680 for special services pricing.
Muzzle Brake – Tax Break Special for AccurateShooter.com Readers
Now through April 17, 2012 (Tax Due Date), Darrell is offering a Muzzle Brake – Tax Break Special for our readers. For all case prep/restoration orders of $50.00 or more, Darrell will ultrasonically clean one or two stainless muzzle brakes for no extra charge (offer does not apply to blued or coated muzzle brakes). For more info, visit DJsBrass.com or call Darrell Jones at 205-461-4680. IMPORTANT: Contact Darrell for shipping instructions BEFORE sending any brass for processing. ALL BRASS MUST BE DE-PRIMED before you send it.
Darrell has cleaned and annealed cases for shooters from across the country. Here are recent testimonials (this Editor reviewed all the original emails so I can confirm these are real):
“Your services were good with a quick turn-around time. Quality of the case annealing looked great[.]” — Tom, in Alaska
“The [300 Win Ackley] batch you did for me came back looking great.” — Chuck, in Arizona
“Since I started using Lapua brass, I’ve gotten gotten enough reloads out of them to notice that the necks were no longer sealing as well as I’d like. A friend suggested annealing them. I remembered seeing DJ’s ad on AccurateShooter.com and thought I’d give him a try. Not only did my [.308 brass] come back sorted exactly as I had sent them out, all had been so thoroughly cleaned that I realized I had been leaving lube on them after forming. DJ had taken the time to enclose a note cautioning me to brush the inside case necks and do a full-length resize for the first loading. And all 200 cases were back in my hands in DAYS, not weeks! Great service, great price, great follow up.” — Jim, in Alabama
Here is a simple technique that can potentially help you load straighter ammo, with less run-out. It costs nothing and adds only a few seconds to the time needed to load a cartridge. Next time you’re loading ammo with a threaded (screw-in) seating die, try seating the bullet in two stages. Run the cartridge up in the seating die just enough to seat the bullet half way. Then lower the cartridge and rotate it 180° in the shell-holder. Now raise the cartridge up into the die again and finish seating the bullet.
Steve, aka “Short Range”, one of our Forum members, recently inquired about run-out apparently caused by his bullet-seating process. Steve’s 30BR cases were coming out of his neck-sizer with good concentricity, but the run-out nearly doubled after he seated the bullets. At the suggestion of other Forum members, Steve tried the process of rotating his cartridge while seating his bullet. Steve then measured run-out on his loaded rounds. To his surprise there was a noticeable reduction in run-out on the cases which had been rotated during seating. Steve explains: “For the rounds that I loaded yesterday, I seated the bullet half-way, and turned the round 180 degrees, and finished seating the bullet. That reduced the bullet runout by almost half on most rounds compared to the measurements from the first test.”
Steve recorded run-out measurements on his 30BR brass using both the conventional (one-pass) seating procedure, as well as the two-stage (with 180° rotation) method. Steve’s measurements are collected in the two charts above. As you can see, the run-out was less for the rounds which were rotated during seating. Note, the change is pretty small (less than .001″ on average), but every little bit helps in the accuracy game. If you use a threaded (screw-in) seating die, you might try this two-stage bullet-seating method. Rotating your case in the middle of the seating process won’t cost you a penny, and it just might produce straighter ammo (nothing is guaranteed). If you do NOT see any improvement on the target, you can always go back to seating your bullets in one pass. READ Forum Thread….
by James Calhoon
(First Printed in Varmint Hunter Magazine, October, 1995)
In the course of talking to many shooters, it has become clear to me that the manufacturers of primers have done a less than adequate job of educating reloaders on the application of their primers. Everybody seems to realize that some primers are “hotter” than others and some seem to shoot better for them than others, but few reloaders know that primers have different pressure tolerances.
Primer Pressure Tolerance
When loading a .223 to the maximum, I was getting primer piercing before I reached case overloading. I don’t know what prompted me to try CCI 450s instead of the 400s which I had been using, but I did. Presto! No more piercing! Interesting!? A primer that has a hotter ignition and yet withstands more pressure! Thats when I decided that it was time to do a dissection of all primers concerned. The chart below shows my results.
By studying the numbers (Cup “A” thickness), one can see which primers in the small rifle sections should be more resistant to primer cratering and/or piercing. Primer cup diameters are all similar and appear to follow a specification, but check out the cup thickness in the small rifle primers (Dimension “A”). Some cups are quite a bit thicker than others: .025″ for CCI 450 vs. .0019″ for Fed 200. Large rifle primers all appear to have the same cup thickness, no matter what the type. (As a note of interest, small pistol primers are .017″ thick and large pistol primers are .020″ thick.)
If you are shooting a 22 Cooper, Hornet, or a Bee, the .020″ cup will perform admirably. But try using the .020″ cup in a 17 Remington and you will pierce primers, even with moderate loads.
Considering that cup thickness varies in the small rifle primers, it is obvious that primer “flatness” cannot solely be used as a pressure indicator.
Another factor which determines the strength of a primer cup is the work-hardened state of the metal used to make the primer cup. Most primers are made with cartridge brass (70% copper, 30% zinc), which can vary from 46,000 psi, soft, to 76,000 psi tensile strength when fully hardened. Note that manufacturers specify the hardness of metal desired, so some cups are definitely “harder” that others.
What does all this mean to the reloader? - Cases that utilize small rifle primers and operate at moderate pressures (40,000 psi) can use CCI 400, Federal 200, Rem 6 1/2, or Win SR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.
- Cases that utilize small rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2.
- All the large rifle primers measured have the same thickness. Therefore choose based on other factors, such as accuracy, low ES/SD, cost, cup hardness, and uniformity.
Hope this clears up some primer confusion. If you want more information about primers, priming compounds, or even how to make primers, the NRA sells an excellent book called “Ammunition Making” by George Frost. This book tells it like it is in the ammo making industry.
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