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March 28th, 2010
Coating bullets with a friction-reducing compound such as Molybdenum Disulfide (Moly) offers potential benefits, including reduced barrel heat, and being able to shoot longer strings of fire between bore cleanings. One of the effects of reduced friction can be the lessening of internal barrel pressures. This, in turn, means that coated bullets may run slower than naked bullets (with charges held equal). To restore velocities, shooters running coated bullets are inclined to “bump up” the load — but you need to be cautious.
Be Careful When Increasing Loads for Coated Bullets
We caution shooters that when your start out with coated bullets in a “fresh barrel” you should NOT immediately raise the charge weight. It may take a couple dozen coated rounds before the anti-friction coating is distributed through the bore, and you really start to see the reduced pressures. Some guys will automatically add a grain or so to recommended “naked” bullet charge weights when they shoot coated bullets. That’s a risky undertaking.
Instead we recommend that you use “naked” bullet loads for the first dozen coated rounds through a new barrel. Use a chronograph and monitor velocities. It may take up to 30 rounds before you see a reduction in velocity of 30-50 fps that indicates that your anti-friction coating is fully effective.
We have a friend who was recently testing moly-coated 6mm bullets in a 6-6.5×47. Moly had not been used in the barrel before. Our friend had added a grain to his “naked” bullet load, thinking that would compensate for the predicted lower pressures. What he found instead was that his loads were WAY too hot initially. It took 30+ moly-coated rounds through the bore before he saw his velocities drop — a sign that the pressure had lowered due to the moly. For the rounds fired before that point his pressures were too high, and he ended up tossing some expensive Lapua brass into the trash because the primer pockets had expanded excessively.
LESSON: Start low, even with coated bullets. Don’t increase your charge weights (over naked bullet loads) until you have clear evidence of lower pressure and reduced velocity.
Procedure After Barrel Cleaning
If you shoot Moly, and clean the barrel aggressively after a match, you may want to shoot a dozen coated “foulers” before starting your record string. Robert Whitley, who has used Moly in some of his rifles, tells us he liked to have 10-15 coated rounds through the bore before commencing record fire. In a “squeaky-clean” bore, you won’t get the full “benefits” of moly immediately.
 To learn more about the properties of dry lubricants for bullets, read our Guide to Coating Bullets. This covers the three most popular bullet coatings: Molybdenum Disulfide (Moly), Tungsten Disulfide (WS2 or ‘Danzac’), and Hexagonal Boron Nitride (HBN). The article discusses the pros and cons of the different bullet coatings and offers step-by-step, illustrated instructions on how to coat your bullets using a tumbler.
March 21st, 2010
 We’ve been upgrading some pages for the website, including this new layout for the AccurateShooter.com Daily Bulletin. We’ve noticed that some features of this page (and on other websites) may not display optimally with earlier versions of Microsoft’s Internet Explorer browser. If, for example, some of the navigation tools don’t work, a browser upgrade will fix that. If you’re still running IE 6.0 or 7.0, we strongly recommend you upgrade to Internet Explorer 8.0. You can also use another type of browser, such as Firefox or Chrome. But for our readers who prefer IE, we advise upgrading to version 8.0.
Compared to IE 7.0, Internet Explorer 8.0 will display most websites faster (with fewer faults) when running XP or Vista, AND it will definitely provide a better browsing experience with the new Windows 7 operating system. Internet Explorer 8.0 also provides enchanced security for all Windows OS types (XP, XP Home, Vista, Windows 7). Internet Explorer 8.0 can be downloaded and used for FREE.
CLICK HERE to go to the Internet Explorer 8 download page.
February 15th, 2010
Has your Windows PC running XP started to slow down? Are you running out of hard drive space? If so, there is a simple procedure for removing accumulated “temp” files that can clog your system when running Windows XP. If you’ve been using your computer for a couple years or more, there could be thousands of temp files hogging space on your hard drive, though they have no function anymore.
Here’s the procedure for deleting unnecessary temp files.
First click on the “Start” button. Next select “Run” from the Menu.
When the “Run” window appears, type in “%temp%” (without quote marks), and click “OK”.
A folder window called “Temp” will appear. All the files and folders in that window can be highlighted and sent to the Recycle Bin. WARNING: If you find some important data files (such as family photos or your IRS tax returns), you may want to move these to another place on the hard drive BEFORE you empty the Recycle bin. But in reality, it’s normally safe to delete any file that displays when you peform the Run > %temp% command. If a file in that temp folder is being used by an active program, Windows won’t let you delete it.
On this editor’s three-year old computer, running Windows XP, there were nearly 18 Gigabytes of temp files that I was able to delete. That freed up a lot of space on my hard-drive, and my computer runs faster now.
If you don’t understand our explanation of the Temp File deletion process using the %temp% command, READ THIS TECH SUPPORT PAGE from About.com.
Note, there are also unused files in the “Temp” sub-folder in your Windows folder on your C:/ Drive. But you need to be a bit more careful deleting those files — so we won’t explain that process here. Just be aware that there may be many more Gigabytes of useless files stored in your computer.
February 13th, 2010
 This may surprise you. We’ve learned that the time interval between neck-sizing operation and bullet seating can have dramatic effects on neck tension (as measured by the force required to seat bullets). Controlling neck tension on your cases is a very, very important element of precision reloading. When neck tension is very uniform across all your brass, you’ll see dramatic improvements in ES and SD, and your groups will shrink. Typically you’ll also see fewer fliers. Right now, most reloaders attempt to control neck tension by using different sized neck bushings. This does, indeed, affect how firmly the neck grips your bullets. But time of loading is another key variable.
James Phillips discovered that time is a critical factor in neck tension. James loaded two sets of 22 Dasher brass. Each had been sized with the SAME bushing, however the first group was sized two weeks before loading, whereas the second group was neck-sized just the day before. James noticed immediately that the bullet seating effort was not the same for both sets of cases — not even close.
 Using a K&M Arbor press equipped with the optional Bullet-Seating Force Gauge, James determined that much more force was required to seat bullets in the cases which had been neck-sized two weeks before. The dial read-out of seating force for the “older” cases was in the 60s, while the seating force for the recently-neck-sized cases was in the 20s. (These numbers loosely correspond to the amount of force required to seat the bullet). Conclusion? In the two weeks that had elapsed since neck-sizing, the necks continued to get tighter and stiffen.
When we first posted this information, it spawned some debate. Many people said they have observed the same thing, but the question is why? Something seems to happen over time that makes the necks less “springy”. Our theory is that, over time, the necks (as sized) are taking a “set” and seem to lose elasticity or the ability to stretch. When they are freshly sized, the neck material seems to be more ductile and expands more readily as the bullet is seated.
In a comment to this post, Steve Blair offered this explanation of how case necks can change over time: “When [metal] material is cold worked, the lattice stresses induced may not be uniform and immediately realized. The grain structure can continue to change for some time, becoming harder and less ductile as the lattice deforms further. Seating a bullet in a case neck provides ongoing radial stress to which the metal will respond over time.”
Concerning the seating force numbers (20 vs. 60) — keep in mind that the K&M simply has a dial read-out activated by a Belleville washer stack with a link rod. This isn’t an ultra-precise measure of force. But you CAN feel the difference between a 20 dial position and a 60. If you use the K&M you’d see what I mean -– the needle tends to swing back and forth as the bullet is seating. What you want to watch for is the max reading and “spikes” in the seating force. I think what is going on is the resistance to seating goes up as the brass becomes less elastic over time.
Lesson learned: For match rounds, size ALL your cases at the same time. If you want to reduce neck tension, load immediately after sizing.
Whether or not you accept the notion that case-neck bullet seating resistance rises with time (you’ll need to do your own experiments), it makes sense to size all your match cases at the same time, and then seat all the bullets you need for a match at the same time. If, for example, you need 200 rounds for an upcoming match, you don’t want to size all 200 cases and seat 100 bullets the same day, and then load the remaining 100 rounds three weeks later. Almost certainly you’ll find some difference in neck tension. That variance in neck tension may show up on the target.
This brings up another point — to minimize velocity variances from round to round, it makes sense to shoot the ammo you load in the same order it was loaded (or exact inverse order). That way, if you have some scale drift over time, causing small changes in powder charges, the shot-to-shot variation is reduced.
January 27th, 2010
 Chip Lohman, Managing Editor of Shooting Sports USA Magazine, has authored an excellent article on barrel maintenance and cleaning. Chip’s article, Let the BARREL Tell You — Match Barrel Care, Part I, appears in the January 2010 edition of Shooting Sports USA, which is FREE online, in a digital e-zine format.
Chip Lohman is a talented writer, an NRA-Certified Instructor, and an active shooter. Like most writers, he maintains a healthy sense of curiosity. The debate about the proper care of a match barrel is a hot one, spiked with folklore and old wives’ tales, Lohman said. He and his staff set out to set the record straight: “We tried to interject some science into the discussion of cleaning a match barrel,” he explained. In his article, Lohman writes:
Why worry about a little barrel fouling when the throat is subjected to a brutal 5,600° F volcano at 55,000 PSI? To investigate these and other questions about taking care of a match barrel, we spoke with a dozen experts and share their knowledge in this first of a series of articles.
After listening to folks who shoot, build barrels or manufacture cleaning solvents for a living, we concluded that even the experts each have their own unique recommendations on how to care for a match barrel. But they all agree on one thing— the gun will tell you what it likes best. Because the life expectancy of a match barrel is about 1,500 to 2,500 rounds, the objectives of cleaning one should include: preserve accuracy, slow the erosion and remove fouling—all without damaging the gun. This article doesn’t claim that one cleaning method is better than the next. Rather, we set out to interject a little science into the discussion and to share some lessons learned from experts in the field.
CLICK HERE to read complete Barrel Care Article in Shooting Sports USA
CLICK HERE to read latest February 2010 Edition of Shooting Sports USA
January 20th, 2010
 At the request of AccurateShooter.com, respected Benchrest ace Lou Murdica tested the brand new, early production Norma 6PPC brass. Lou shot 30 cases (both turned and unturned) over the past few days, and he endorses the Norma brass without hesitation. Lou says “the Norma PPC brass is great brass. Without a doubt this will be highly competitive brass in the short-range benchrest group”. Lou did observe that the necks on the Norma brass were slightly thinner than on Lapua 220 Russian brass, but that really doesn’t matter. With a slight neck turn, Lou declares, “the Norma PPC brass is as good as any out there.”
Lou said, based on his testing, the Norma brass holds pressure well, and the accuracy is outstanding. Lou shot five 5-round groups, as in a match course of fire, and his largest group was “around 0.148″ at 100 yards.
If you’re a short-range benchrester, definitely watch this video and listen to Lou. He thinks this new Norma brass will “change the game”. Note — Lou said most PPC shooters can shoot the Norma cases with no change in their powder recipes. So you won’t lose any velocity using Norma’s new brass. Lou was very impressed with Norma’s new offering, enough so that he declared: “I would go right for the Norma right now if I could put a bunch in my hand.”
December 6th, 2009
 The RCBS ChargeMaster 1500 electronic powder scale and dispenser is the most popular product of its kind on the market. In our original Electronic Powder Dispenser Comparison Test, the ChargeMaster normally dispensed most kinds of powder faster than competitive units from Lyman and PACT. However, after the initial release of the ChargeMaster 1500, RCBS “tweaked” the software a bit to achieve more consistent charge-throws. This slowed down the process somewhat. Some owners have wanted to speed up their ChargeMaster. This IS possible with a relatively simple reprogramming. Most of the internal parameters of the Chargemaster can be modified, under guidance from the tech staff at RCBS.
Gunsmith and Forum member NAT Lambeth reports: “I thought My RCBS ChargeMaster 1500 Combo was fast enough. But I still called RCBS and asked for the programing changes to see if I could speed it up. It was a lot easier than I thought. My 1500 Combo was taking from 15-30 seconds to dispense the powder to the tenth of a grain. I reprogrammed the numbers and now it takes between 7 and 15 seconds to dispense to a tenth. This effectively doubled my loading speed. I only changed the HSB_A1, HSB_B1, and BSP_C1 settings.”
Key ChargeMaster Parameters with Default Settings
HSB_A1 (15.68) Grains under target weight to go from full to high speed
HSB_B1 (3.42) Grains under target weight to go from high to slow speed
BSP_C1 (1.08) Grains under target weight to go from slow to final trickle speed
Nat cautions that you should talk to a RCBS tech before attempting to re-program your ChargeMaster: “You will benefit from talking to the RCBS tech. I have now gone back and played with the numbers a couple of times. (The numbers given to me by the tech at RCBS were still a little conservative.) I think each machine may have its own likes and dislikes. If you get too aggresive with lowering your numbers it will over-throw your intended load.”
 Source for ALL the Parameters
There is an extensive discussion of RCBS ChargeMaster programming on the South Africa Hunting Rifle Shooting Assn. (SAJSV) Forum. In this SAJSV Forum ARTICLE, Jaco Brink lists virtually all the programming codes. Importantly, Jaco also provides the default values for various parameters. This is very important, because the ChargeMaster does not have a “return to default” option. Once you change any value, if you want to return to the original value you must enter it manually. Jaco cautions: “I have to advise you to only make changes to your scale if you are confident to do so, and remember that there is not a ‘return to default’ setting in the scale. If all else fails return your scale to the default settings [I have listed].”
CLICK HERE for list of RCBS ChargeMaster Default Programming Values
Use a McDonald’s Straw to Reduce “Over-Throws”
Jaco Brink provided another useful tip to avoid “over-throws” (excess charge weight): “The RCBS employee advised me to take a McDonnell’s straw (because it is thicker than a normal straw), cut off about a half inch piece and put it into the tube where the powder exits. This caused the last [few kernels] of an extruded powder to cluster less, and reduced the amount of overthrows dramatically.”
CLICK HERE for more ChargeMaster 1500 optimization TIPS.
October 24th, 2009
We are often asked “Can I get more velocity by switching primer types?” The answer is “maybe”. The important thing to know is that changing primer types can alter your load’s performance in many ways — velocity average, velocity variance (ES/SD), accuracy, and pressure. Because there are so many variables involved you can’t really predict whether one primer type is going to be better or worse than another. This will depend on your cartridge, your powder, your barrel, and even the mechanics of your firing pin system.
Interestingly, however, a shooter on another forum recently did a test with his .308 Win semi-auto. Using Hodgdon Varget powder and Sierra 155gr Palma MatchKing (item 2156) bullets, he found that Wolf Large Rifle primers gave slightly higher velocities than did CCI-BR2s. Interestingly, the amount of extra speed (provided by the Wolfs) increased as charge weight went up, though the middle value had the largest speed variance. The shooter observed: “The Wolf primers seemed to be obviously hotter and they had about the same or possibly better ES average.” See table:
| Varget .308 load |
45.5 grains |
46.0 grains |
46.5 grains |
| CCI BR2 Primers |
2751 fps |
2761 fps |
2783 fps |
| Wolf LR Primers |
2757 fps |
2780 fps |
2798 fps |
| Speed Delta |
6 fps |
19 fps |
15 fps |
You can’t extrapolate too much from the table above. This describes just one gun, one powder, and one bullet. Your Mileage May Vary (YMMV) as they say. However, this illustration does show that by substituting one component you may see significant changes. Provided it can be repeated in multiple chrono runs, an increase of 19 fps (with the 46.0 grain powder load) is meaningful. An extra 20 fps or so may yield a more optimal accuracy node or “sweet spot” that produces better groups. (Though faster is certainly NOT always better for accuracy — you have to test to find out.)
WARNING: When switching primers, you should exercise caution. More speed may be attractive, but you have to consider that the “speedier” primer choice may also produce more pressure. Therefore, you must carefully monitor pressure signs whenever changing ANY component in a load.
Plenty of CCI-BR2 and Wolf Large Rifle Primers in Stock
If you’re looking for either the CCI BR-2 or Wolf Large Rifle Primers, Wideners.com currently has both in stock. The CCI BR2 primers (item CCIBR2) cost $42.50 per 1000. The Wolf LR Primers (item QQQLR KVB-7) cost $29.50 per 1000 OR $142.00 per 5000.
October 17th, 2009
LINK: Advanced Ballistics Program for I-Phones and I-Pods
Apple’s I-Phone and I-Pod offer a superb user interface with serious computing power. Here’s a very trick software App (good enough for the U.S. military) that runs ballistic calcs and even has a bullet database.
September 27th, 2009
 Forum Member Dave B., aka “Gunamonth”, is a chemist/physicist with decades of experience working with the ultrasound process. He has achieved great results cleaning cases via ultrasound. Dave tried a variety of solutions and he favors a mix of water and Citranox®. This achieved the best results, and did not require a separate neutralizing step if you rinse the cases thoroughly after. Citranox, mixed 1:75 or 1:100 with water (distilled H20 is best), is inexpensive to use. Phospate-free Citranox® contains a blend of organic acids, anionic and non-ionic surfactants and alkanolamines. For more information on using Citranox®, check out THIS FORUM THREAD.
Dave notes: “I had a lot of communication with the technical VP of Alconox about trying to clean fired cases with an ultrasonic unit. He sent me a copy of his ultrasonic cleaning manual and recommended a product called Citranox®. So far I’ve been very impressed. With once- or twice-fired brass they clean up very quickly. The worst cases I tried were 6 Dashers that had been fired ten times with Varget and never cleaned. The worst fouling was in the bottom of the case around the flash hole. They took longer and I used a more concentrated cleaning solution but they did come out clean. The price is reasonable. I paid $35 a gallon and for once- or twice-fired cases I dilute the cleaner 100 to 1. There is much less chemical reaction with the brass than there is with vinegar. No weird colors, just shiny bright. I even used it with hot water, which speeds up the cleaning process. No need to neutralize. Just rinse in running water and they’re squeaky clean. The cleaner is mostly detergents with a little citric acid. Even at a 1:75 ratio my $35 worth of cleaner will make 75 gallons of solution. It doesn’t seem to be reusable but 75 gallons is a whole lot of solution when I only use about two cups at a time.”
The price has gone up a bit since Dave acquired his Citranox, but Amazon.com sells Citranox for $40.00 per gallon, or you can buy a gallon of Citranox from LabSafety Supply for $46.40.
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