Do you use bushings to size your case-necks? Are you assuming that your bushings are actually round on the inside, with a hole that’s centered-up properly? Well you may be in for an unpleasant surprise, based on what our friend Jim de Kort recently discovered. Jim was concerned about the run-out on his brass. His cases went into his bushing-equipped FL die pretty straight, but came out of the die with up to .004″ run-out. “What gives?”, Jim wondered. “Could the problem be the bushings themselves?”
To answer that question, Jim decided to examine his bushings. Using an Accuracy One Wheel-drive concentricity gauge, Jim checked out some of his neck bushings. What he discovered may surprise you…
Neck Bushing Flaws Revealed
Trust no one… — Jim de Kort
Jim writes: “I measured the concentricity of my 6BR rounds today. I noticed they went into the neck-bushing equipped full-length sizing die with less than .001″ deviation but came out with .003-.004″. The culprit, it appears, was the bushing itself. Without it the cases stayed within .0005″ to .001″ deviation, so something was happening with the bushing.
One bushing had .00025″ deviation on the outside, yet almost .003″ on the inside, so it is crooked. But even when using a bushing that is within .001″ I still get .003″ runout after sizing. I repeated the same procedure for my 6×47 and got the same results. When using the bushing, concentricity suffers a lot.”
Before we bash the bushing-makers, we must acknowledge that many different things can contribute to excessive run-out and/or mis-alignment of case-necks. We don’t have all the answers here, and Jim would be the first to say that some mysteries remain. Still, these are interesting results that give all precision hand-loaders something to think about.
Jim Borden of Borden Accuracy also offers this tip: “Check the trueness of the face of the die cap. That has more to do with trueness than the bushing. Also check perpendicularity of hole in bushing to top surface. When I was making dies, the cap was made by threading and facing the threaded tenon in same setup.”
Editor’s Comment: Many people have great results with neck-bushing dies, but Jim isn’t the only fellow who has seen some very odd results. I personally employ honed, non-bushing dies for many of my chamberings. These non-bushing dies (with the necks honed for .002-.003″ neck tension) produce extremely straight ammo, with run-out consistently under .0015″.
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There is an excellent article about primers on the Shooting Times website. We strongly recommend you read Mysteries And Misconceptions Of The All-Important Primer, written by Allan Jones. Mr. Jones is a bona fide expert — he served as the manager of technical publications for CCI Ammunition and Speer Bullets and Jones authored three editions of the Speer Reloading Manual.
This authoritative Shooting Times article explains the fine points of primer design and construction. Jones also reveals some little-known facts about primers and he corrects common misconceptions. Here are some highlights from the article:
Size Matters
Useful Trivia — even though Small Rifle and Small Pistol primer pockets share the same depth specification, Large Rifle and Large Pistol primers do not. The standard pocket for a Large Pistol primer is somewhat shallower than its Large Rifle counterpart, specifically, 0.008 to 0.009 inch less.
Magnum Primers
There are two ways to make a Magnum primer — either use more of the standard chemical mix to provide a longer-burning flame or change the mix to one with more aggressive burn characteristics. Prior to 1989, CCI used the first option in Magnum Rifle primers. After that, we switched to a mix optimized for spherical propellants that produced a 24% increase in flame temperature and a 16% boost in gas volume.
Foiled Again
Most component primers have a little disk of paper between the anvil and the priming mix. It is called “foil paper” not because it’s made of foil but because it replaces the true metal foil used to seal early percussion caps. The reason this little disk exists is strictly a manufacturing convenience. Wet primer pellets are smaller than the inside diameter of the cup when inserted and must be compacted to achieve their proper diameter and height. Without the foil paper, the wet mix would stick to the compaction pins and jam up the assembly process.
Primer Functionality and Primer Types Compared
This video looks at a variety of primer types from multiple manufacturers, foreign and domestic. The video explains the basics of how primers function, and then explains the key characteristics of standard primers, magnum primers, and mil-spec primers (designed for semi-auto rifles).
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With the Whidden Click-Adjustable Sizer Dies, you can change shoulder bump by .001″ (one-thousandth) with a simple click. Fast. Easy. Precise.
As handloaders have become more aware of shoulder bump and proper adjustment of the sizer die in recent years, there has become a need for an easier way to adjust the sizer die properly. For most folks, with their conventional dies, it takes lengthy trial trial and error to get the shoulder setback correct. Anyone who has done this can attest that it can be a slow and annoying job.
Whidden Gunworks has solved the problem with the innovative Click Adjustable Sizer Die. Patent No: 10,393,488. This die and lock ring work together to give the user a clicking feel to the adjustment just like a high end rifle scope. Each click moves the shoulder bump exactly .001″ so you can easily find the exact shoulder bump that you desire.
The Click Adjustable option is available on Whidden Custom Sizer dies as well (7/8”-14 format dies only)! Included with the Click Adjustable Sizer Die is a Shoulder Bump Gauge. This gauge attaches to standard calipers and allows measurement from the case shoulder to the base. Using the Shoulder Bump Gauge with the Click Adjustable Sizer Die will make the proper sizer die setup easier than ever before.
Click-adjustable die sets are available with both bushing and non-bushing configurations. Along with these complete die sets, Whidden Gunworks offers a separate click-adjustable ring to use with existing dies. Priced at $58.99, the Whidden Click-Adjust Lock Ring represents a modest investment for a major gain in die ease-of-use and precision adjustability.
The Whidden Universal Click Adjustable Lock Ring you can instantly turn your sizer die into a Click Adjustable Die. This ring works with any 7/8 OD sizer of any brand with adjustable shoulder bump. Simple in design, the inner and outer ring can rotate independently of each other. Each click is metered in true 1 thousandths adjustment and has 0.100″ total available travel. These work great with nearly all sizing 7/8 OD sizing dies, and one verified purchaser noted: “Not only are they useful on reloading dies, but it’s the cat’s meow on the Giraud Power Trimmer Case Holders.”
Dillon Users Take Note: The Whidden Click Adjustable Sizing Die will not work with the Dillon 550 or 650 progressive reloading press systems. The Universal Click Adjustable Lock Ring is not compatible with the Dillon floating toolhead.
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The Shooting Sports USA website includes two excellent articles about the basics of metallic cartridge reloading. These two articles provide an excellent summary of the key procedures. If you are new to reloading, we recommend you read both articles:
Part II is particularly helpful because it explains the entire reloading process step-by-step, with 14 listed steps. The author notes: “In this, the second installment on metallic cartridge reloading, we’ll follow the sequence of steps involved in reloading a rifle cartridge and refining a metallic cartridge load. These steps are based on the use of a single-stage reloading press and a separate priming tool.”
Much important advice is provided as this article runs through the 14 Steps of Reloading. For example, when explaining Step 13, Bullet Seating, the article states:
“Proper seating depth is critical. Too much bullet protrusion and the cartridge may not work through the gun’s magazine, or it may fail to chamber. Too little and the bullet intrudes excessively into the powder chamber, decreasing volume and raising pressure. Neck tension is also important; any bullet that fails to seat with some resistance may be held only loosely by the neck and may be driven back into the case when the round is chambered, especially in semi-automatic arms.”
Important Guide to Detecting Over-Pressure Signs in Brass
As an example of the invaluable advice provided in these two articles, here’s a sample from Part II that explains how to determine if your load is over-pressure. We recommend that EVERY reader read this twice. There are more things to consider than a stiff bolt lift. You need to inspect cartridges very carefully:
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Before you load that nice new cartridge brass for the first time, run an expander mandrel down the case necks. This will iron out dents and provide more uniform neck tension. Chose a mandrel diameter that provides appropriate neck tension.
Lapua brass is so good that you’ll be tempted to just load and shoot, if you have a “no-turn” chamber. However, some minimal case prep will ensure more uniform neck tension. Keeping your neck tension very uniform allows more consistent bullet seating. That, in turn, usually yields better accuracy, and lower Extreme Spread and Standard Deviation (ES/SD). Lapua brass, particularly 6mmBR, 6.5×47, 6.5 Creedmoor, and .308 Win comes from the factory with tighter-than-optimal necks. Before you seat bullets, at a minimum, you should inside chamfer the case mouths, after running an expander mandrel down the necks. The expander mandrels from both Sinclair Int’l and K&M will both leave the necks with enough neck tension (more than .001″) so you can then seat bullets without another operation. We suggest putting a bit of lube on the mandrel before running it down the necks — but remove any lube that gets inside the necks before seating bullets.
Both Sinclair and K&M Tools make a die body specifically to hold expander mandrels. The Sinclair version, is shown above. This $45.99 unit fits caliber-specific expander mandrels ($10.99) which measure approximately .001″ less than bullet diameter for each caliber. This is an updated “Gen II” design that completely captures the mandrel within the die so the mandrel cannot pull out. It also has an O-ring in the die cap that allows the mandrel to self-center within the case neck. Brownells offers two sizes of Sinclair die bodies for expander mandrels: .17 -.338 Caliber (#749011715 $45.99); and .357 – .50 caliber (#749008843, $45.99). All Generation II dies are machined from stainless steel and the standard diameter 7/8-14 dies include the Sinclair Stainless Steel Split Lock Ring.
Once you run the Sinclair expander mandrel down the necks of Lapua brass, after you account for brass spring-back, you’ll have about .002″ neck tension*. This will make the process of seating bullets go much more smoothly, and you will also iron out any dents in the case mouths. Once the case mouths are all expanded, and uniformly round, then do your inside neck chamfering/deburring. The same expander mandrels can be used to “neck-up” smaller diameter brass, or prepare brass for neck-turning.
Forum member Mike Crawford adds: “These expanders can also reduce runout from offset seating. Prior to bullet seating, expand the sized necks to force thickness variance outward. With the Sinclair system, the necks will springback fine, and will not be pulled out of center. This leaves plenty of tension, and bullets seated more centered. I do this, even with turned necks, to get improved seating.”
Mandrels vs. Expander Balls on Decapping Rods
If you haven’t acquired an appropriate expander mandrel for your brass, but you DO have a full-length sizing die with an expander ball, this will also function to “iron out” the necks and reduce tension. However, using a die with an expander ball will work the necks more — since you first size them down, then the ball expands them up again. Typically (but not always), run-out is worse when using an expander ball vs. an expander mandrel.
* This .002″ tension is what we have observed with Lapua 6mmBR, 6.5×47, 6.5 Creedmoor, and .308 Win brass. This might vary with much smaller or larger cases, and of course a different brand of brass might yield different results. If you get too little tension with your current mandrel, you can get a smaller-diameter mandrel from 21st Century Shooting. 21st Century even offers low-friction Titanium Nitride-coated mandrels.
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He who dies with the most toys wins — right? Well Sinclair has another interesting gadget you can add to your reloading bench. The Sinclair Case Neck Sorting Tool lets you quickly sort brass by neck-wall thickness. For those who shoot “no-turn” brass, this can improve neck-tension consistency. Large variances in neck-wall thickness can cause inconsistent neck “grip” on the bullet. Generally, we’ve found that more consistent neck tension will lower ES and (usually) improve accuracy. We know some guys who shoot no-turn 6mmBR brass in competition with considerable success — but their secret is pre-sorting their brass by neck-wall thickness. Cases that are out-of-spec are set aside for sighters (or are later skim-turned).
Watch Case Neck Sorting Tool Operation in Video
How the Case Neck Sorting Tool Works
Here’s how the Sinclair tool works. Cases are rotated under an indicator tip while they are supported on a case-neck pilot and a support pin through the flash hole. The unit has a nice, wide base and low profile so it is stable in use. The tool works for .22 through .45 caliber cases and can be used on .17- and .20-caliber cases with the optional carbide alignment rod. The MIC-4 pin fits both .060 (PPC size) and .080 (standard size) flash holes. Sinclair’s Case Neck Sorting Tool can be ordered with or without a dial indicator. The basic unit without dial indicator (item item 749006612) is priced at $59.99. You can also buy the tool complete with dial indicator (item 749007129) for $89.99. IMPORTANT: This sorting tool requires caliber-specific Case Neck Pilots which must be ordered separately.
Editor’s Comment: The purpose of this Sinclair tool is rapid, high-quantity sorting of cartridge brass to ascertain significant case-neck-wall thickness variations. Consider this a rapid culling/sorting tool. If you are turning your necks, you will still need a quality ball micrometer tool to measure neck-wall thickness (to .0005) before and after neck-turning operations.
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Shown are funnel with ultra-long drop tube (which helps get more kernels in the cases), RCBS Chargemaster (in wood box), and Hood Press (similar to Harrell’s Combo press).
Loading at the range remains important in the Benchrest for Group discipline. In a Special Report below, past IBS President Jeff Stover explains how loading methods (and hardware) have evolved over the years. The advent of accurate, affordable electronic powder dispensers, such as the RCBS ChargeMaster and Frankford’s new Intellidropper, have changed the game and made it easier to load efficiently at the range. And quality manual powder measures are fast and can be very consistent, with a little practice. Loading at the range permits competitors to tune their load to the conditions, change seating depths, or even choose different bullets to suit the barrel’s preferences on any given day.
Although pre-loading is not uncommon, most 100/200-yard group shooters usually load at the match, often between relays. The goal is to shoot smaller groups by staying “in tune”. In a game where 5-shot groups “in the 1s and Zeros” is the goal, tuning loads for the conditions helps deliver match-winning accuracy. Nearly all competitors in this short-range discipline shoot the 6mm PPC cartridge, or a PPC variant.
Loading at the Range — Then and Now
In benchrest shooting for group, loading at the range has been de rigueur for decades. In the Score discipline, preloading is usually the custom. The main reason is that, in Score competition, only one Aggregate (warm-up match and five record targets) per day is usually shot. That would be less than 50 shots, assuming a few sighter shots. Also, the 30BR, the dominant Benchrest-for-Score cartridge, is very amenable to pre-loading.
By contrast, the Group discipline includes 21 targets (two warm-ups and twenty record targets) over a weekend, usually shot with 6PPC-chambered rifles. Many times, the 6PPC shooters may tweak their loads through the day given changing atmospheric conditions or simply trying to find the correct tune to “dot up”. This term, “Dot up”, means the shots are essentially going through the same hole, or closely so.
Loading at the range was a bit different when benchrest competition was in its infancy. The 1951 book, Modern Accuracy by Bob Wallack, is the best of the early benchrest books. Copies can be found, from time to time, on eBay or Alibris. It is a fascinating survey of benchrest as it existed more than six decades ago. There’s even coverage of a controversial target that was argued over at the time. In it, there is a photo of Wallack using the rear bumper of a car at the bench to clamp his reloading tools. Things have come a long way compared to the range loading set-ups of modern shooters. Here you can see Bob Wallack way back in 1950:
Modern loading bench set-ups shown in this Special Report belong to top shooters Howie Levy, Bob Hamister, and Kent Harshman.
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If you don’t match your ammo to your chamber, bad things can happen, that’s for sure. A while back, Forum member BigBlack had an experience at the gun range that reminds us of the importance of safety when shooting. He encountered evidence that someone had fired the wrong cartridge in a 7mm WSM rifle. The problem is more common than you may think. This Editor has personally seen novices try to shoot 9mm ammo in 40 S&W pistols. BigBlack’s story is along those lines, though the results were much more dramatic. It’s too bad a knowledgeable shooter was not nearby to “intervene” before this fellow chambered the wrong ammo.
7mm-08 is Not the Same as a 7mm WSM
BigBlack writes: “I know this has probably been replayed a thousand times but I feel we can never be reminded enough about safety. This weekend at the range I found a ruptured case on the ground. My immediate thoughts were that it was a hot load, but the neck area was begging for me to take a closer look, so I did. I took home the exploded case and rummaged through my old cases until I found a close match. From my investigative work it appears someone shot a 7mm-08 in a 7mm WSM. Take a look. In the above photo I’ve put together a 7mm WSM case (top), the ruptured case (middle), and a 7mm-08 case (bottom).”
The photo reveals what probably happened to the 7mm-08 case. The shoulder moved forward to match the 7mm WSM profile. The sidewalls of the case expanded outward in the much larger 7mm WSM chamber until they lacked the strength to contain the charge, and then the case sides ruptured catastrophically. A blow-out of this kind can be very dangerous, as the expanding gasses may not be completely contained within the action.
Can’t Happen to You? Think Again.
This kind of mistake — chambering the wrong cartridge — can happen to any shooter who is distracted, who places even a single wrong round in an ammo box, or who has two types of ammo on the bench. One of our Forum members was testing two different rifles recently and he picked up the wrong cartridge from the bench. As a result, he fired a .30-06 round in a .300 Win Mag chamber, and the case blew out. Here is his story:
“I took two of my hunting rifles I have not used for over 25 years to the range yesterday to get new scopes on paper, a .30-06 and .300 Win Mag. I had four boxes of old Winchester factory ammo (two of each cartridge), which had near identical appearances. I accidentally chambered a .30-06 round in the Sako .300 Win Mag rifle. It sprayed powder on my face and cracked the stock at the pistol grip. If I had not been wearing safety glasses I might be blind right now.
You should always wear protective eyewear, EVERY time you shoot.
“I feel lucky and am very thankful for being OK — other than my face looks funny right now. I am also grateful for learning a valuable lesson. I will never put two different cartridges on the bench at the same time again.”
The U.S. Army Marksmanship Unit published a series of reloading “how-to” articles on the USAMU Facebook page. A while back the USAMU’s reloading gurus looked at the subject of cartridge run-out and what can be done to produce straighter ammo. Tasked with producing thousands of rounds of ammo for team members, the USAMU’s reloading staff has developed smart methods for improving concentricity, even with budget-priced dies. For other hand-loading tips, visit the USAMU Facebook page.
Minimizing Runout with Standard Seating Dies
This USAMU article explains how to set up standard bullet seating dies dies to minimize Total Indicated Run-out (TIR). The loading process is described using a single-stage press since most handloaders have one. A high-quality run-out gauge is essential for obtaining consistent, accurate results.
Having sized, primed, and charged our brass, the next step is bullet seating. Many approaches are possible; one that works well follows. When setting up a standard seating die, insert a sized, trimmed case into the shellholder and fully raise the press ram. Next, back the seating stem out and screw the die down until the internal crimping shoulder touches the case mouth.
Back the die out ¼ turn from this setting to prevent cartridge crimping. Next, lower the press ram and remove the case. Place a piece of flat steel (or window glass, which is quite flat) on the shellholder and carefully raise the ram.
Place tension on the die bottom with the flat steel on the shellholder. This helps center the die in the press threads. Check this by gently moving the die until it is well-centered. Keeping light tension on the die via the press ram, secure the die lock ring. If one were using a match style, micrometer-type seating die, the next step would be simple: run a charged case with bullet on top into the die and screw the seating stem down to obtain correct cartridge OAL.
However, with standard dies, an additional step can be helpful. When the die has a loosely-threaded seating stem, set the correct seating depth but don’t tighten the stem’s lock nut. Leave a loaded cartridge fully raised into the die to center the seating stem in the die. Then, secure the stem’s lock nut. Next, load sample cartridges and check them to verify good concentricity.
One can also experiment with variations such as letting the seating stem float slightly in the die to self-center, while keeping correct OAL. The run-out gauge will show any effects of changes upon concentricity. However, this method has produced excellent, practical results as evidenced by the experiment cited previously. These results (TIR Study 2) will reproduced below for the reader’s convenience.
First, however, let’s examine run-out figures of some factory-loaded match ammunition. This should give readers who are new to TIR gauges some perspective about the TIR ranges one might encounter.
TIR Study 1: 50 rounds Lake City M852 Match 7.62mm
(168 gr. Sierra MatchKings)
0.000” – 0.001” = 2%
0.001” – 0.002” = 30%
0.002” – 0.003” = 16%
0.003” – 0.004” = 22%
0.004” – 0.005” = 14%
0.005” – 0.006” = 14%
0.006” – 0.007” = 0%
0.007” – 0.008” = 2%
TIR Study 2: 50 rounds of .308 match ammo loaded using carefully-adjusted standard dies, vs. 50 using expensive “Match” dies from the same maker.
Standard dies, TIR:
0.000” — 0.001” = 52%;
0.001”– 0.002” = 40%;
0.002”– 0.003” = 8%.
None greater than 0.003”.
Note: both samples were loaded using the O-Ring method, i.e. with a rubber O-Ring placed under the locking ring of the Full-length sizing die to allow that die to float.
These tips are intended to help shooters obtain the best results from inexpensive, standard loading dies. Especially when using cases previously fired in a concentric chamber, as was done above, top-quality match dies and brass can easily yield ammo with virtually *no* runout, given careful handloading.
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When neck-turning cases, it’s a good idea to extend the cut slightly below the neck-shoulder junction. This helps keep neck tension more uniform after repeated firings, by preventing a build-up of brass where the neck meets the shoulder. One of our Forum members, Craig from Ireland, a self-declared “neck-turning novice”, was having some problems turning brass for his 20 Tactical cases. He was correctly attempting to continue the cut slightly past the neck-shoulder junction, but he was concerned that brass was being removed too far down the shoulder.
Craig writes: “Everywhere I have read about neck turning, [it says] you need to cut slightly into the neck/shoulder junction to stop doughnutting. I completely understand this but I cant seem to get my neck-turning tool set-up to just touch the neck/shoulder junction. It either just doesn’t touch [the shoulder] or cuts nearly the whole shoulder and that just looks very messy. No matter how I adjust the mandrel to set how far down the neck it cuts, it either doesn’t touch it or it cuts far too much. I think it may relate to the bevel on the cutter in my neck-turning tool…”
Looking at Craig’s pictures, we’d agree that he didn’t need to cut so far down into the shoulder. There is a simple solution for this situation. Craig is using a neck-turning tool with a rather shallow cutter bevel angle. This 20-degree angle is set up as “universal geometry” that will work with any shoulder angle. Unfortunately, as you work the cutter down the neck, a shallow angled-cutter tip such as this will remove brass fairly far down. You only want to extend the cut about 1/32 of an inch past the neck-shoulder junction. This is enough to eliminate brass build-up at the base of the neck that can cause doughnuts to form.
The answer here is simply to use a cutter tip with a wider angle — 30 to 40 degrees. The cutter for the K&M neck-turning tool (above) has a shorter bevel that better matches a 30° shoulder. There is also a 40° tip available. PMA Tool and 21st Century Shooting also offer carbide cutters with a variety of bevel angles to exactly match your case shoulder angle*. WalkerTexasRanger reports: “I went to a 40-degree cutter head just to address this same issue, and I have been much happier with the results. The 40-degree heads are available from Sinclair Int’l for $15 or so.” Forum Member CBonner concurs: “I had the same problem with my 7WSM… The 40-degree cutter was the answer.” Below is Sinclair’s 40° Cutter for its NT-series neck-turning tools. Item NT3140, this 40° Cutter sells for $14.99. For the same price, Sinclair also sells the conventional 30° Cutter, item NT3100.
Al Nyhus has another clever solution: “The best way I’ve found to get around this problem is to get an extra shell holder and face it off .020-.025 and then run the cases into the sizing die. This will push the shoulder back .020-.025. Then you neck turn down to the ‘new’ neck/shoulder junction and simply stop there. Fireforming the cases by seating the bullets hard into the lands will blow the shoulder forward and the extra neck length you turned by having the shoulder set back will now be blended perfectly into the shoulder. The results are a case that perfectly fits the chamber and zero donuts.”
The last half-inch or so of your barrel is absolutely critical. Any damage (or abnormal wear) near the crown will cause a significant drop-off in accuracy. Here are ways you can check the end of your barrel, using a common Q-Tip.
Use Q-Tip for Barrel Inspection
To find out if you have a burr or damage to your crown, you can use an ordinary Q-tip cotton swab. Check the edges of the crown by pulling the Q-tip gently out past the edge of the crown. If you have a burr, it will “grab” the cotton and leave strands behind.
Larry Willis has another way to use a Q-Tip: “Here’s a neat trick that will surprise you with how well it works.” Just insert a Q-Tip into your barrel (like the picture below), and it will reflect enough light so that you can get a real good look at the last half inch of rifling and the crown of your barrel. In most cases you’ll find that this works much better than a flashlight. Larry tells us: “I’ve used this method about a jillion times. Q-Tips are handy to keep in your cleaning supplies anyway. This is a good way to judge approximately how well you are cleaning your barrel when you’re at the range. It’s also the best way to examine your barrel when you’re in the field.”
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.
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.
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He who dies with the most toys wins — right? Well Sinclair has another interesting gadget you can add to your reloading bench. The Sinclair 
When neck-turning cases, it’s a good idea to extend the cut slightly below the neck-shoulder junction. This helps keep neck tension more uniform after repeated firings, by preventing a build-up of brass where the neck meets the shoulder. One of our Forum members, Craig from Ireland, a self-declared “neck-turning novice”, was having some problems turning brass for his 20 Tactical cases. He was correctly attempting to continue the cut slightly past the neck-shoulder junction, but he was concerned that brass was being removed too far down the shoulder.
The last half-inch or so of your barrel is absolutely critical. Any damage (or abnormal wear) near the crown will cause a significant drop-off in accuracy. Here are ways you can check the end of your barrel, using a common Q-Tip.
