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October 21st, 2008
How long will a barrel last before the accuracy “goes south”? There are so many variables involved (powder type, bore diameter, bullet coatings etc.) that it’s hard to predict. You might say “Well, my buddy has a .243 and he got 1500 rounds before the throat was shot out” — those kind of comparisons can be useful, but they’re not very scientific, and they won’t help much if you’ve got a gun in a new chambering (such as the 6.5×47) for which there is not a lot of historical data.
Is there a more reliable way to predict barrel life — one that will work for a broad range of calibers? Well, Forum member MikeCr has developed an Excel spreadsheet that accounts for a number of variables, and gives a pretty good estimate of useful barrel life, whether you’re shooting a .223 Rem or a 338 Lapua Magnum. Mike’s program predicts barrel life using five variables: 1) Bullet Diameter; 2) Powder Charge weight; 3) Powder Heat Potential (KJ/kg); 4) Pressure (in psi); and 5) Bullet Coating (yes/no). Mike provides a table with Heat Potential ratings for most popular powder types. The user needs to know the pressure of his load. This can be estimated with QuickLOAD.
You can download the lastest version of Mike’s spreadsheet below. You’ll need an Excel viewer to open the file.
Click to Download Spreadsheet: Barrel Life Spreadsheet (Lastest Version)
Shown below is Mike’s Spreadsheet, with variables for a 6BR shooting 105gr “naked” bullets with 30.3 grains of Hodgdon Varget powder. The formula predicts 2401 rounds of barrel life. That corresponds pretty well to what we’d expect for a 6BR — about 2500 rounds.
 
Mike observes: “There has been alot of discussion lately related to cartridge design and resulting barrel life. This is a really important factor to consider amongst a myriad of choices. Barrel life is controversial, and subjective. There are no clear-cut standards for comparison. But a few years ago, I put together a spreadsheet based on Bart Bobbit’s rule of thumb. It worked pretty good, only occasionally failing some tests when validated against posted barrel lives.
According to Ken Howell, I had to account for pressure. And Henry Child’s powder temperature testing provided another piece needed. So, I’ve tweaked it here and there to pass more tests. From 223rem to 300 UltraMagnum. Another element added, but turned off is shot interval. I would need way more tests to lock in on this. But everyone knows, the faster you shoot, the worse the barrel life.
Anyway, another factor hard to define is ‘accurate’ barrel life. This cannot be quantified without standards. Barrels are replaced when expectations are no longer met. I feel that a [barrel] passes peak potential in a finite period due to throat erosion. But that don’t mean it’s toast, if it still shoots well enough. It’s just as likely that many of us never see that peak potential anyway. It’s a slippery thing. Point-blank BR competitors will toss a barrel when it leaves the 1s. I could get another 4000 rounds from it, and be content with its performance, I’m sure.
NOTE: This spreadsheet may show a lower barrel life than you prefer. But it pretty well spotlights cartridges to stay away from if you plan much time at the range or in dog town.”
Editor’s Comment: We want to stress that Mike’s spreadsheet is a helpful tool, but it is not a definitive “take-it-to-the-bank” indicator of barrel life. Mike cautions that predicting barrel life involves so many different factors (including how hard/hot the barrel is run), that the task is a bit like predicting tread life on car tires. Still, the spreadsheet is very helpful. It can certainly put shooters on notice that some chamberings (such as the 6-284) are likely to be a barrel burners. That can help you make a smart decision when choosing a chambering for your next rifle.
October 16th, 2008
Confused about the meaning of a term such as “meplat”, “magnaflux” or “obturate”? Need to know the OAL of an unusual Wildcat such as the .218 Donaldson Wasp? Well CCI and MidwayUSA offer handy answers on the web. CCI’s Shooters’ Glossary is a very complete collection of gun-related and reloading terms. MidwayUSA’s GunTEC Dictionary contains short descriptions of hundreds of cartridges, plus definitions of thousands of shooting-related words and phrases. How many of you knew that “Maggie’s Drawers” is “a colloquial term used for the red flag once used by pit workers to signal a missed shot at high-power rifle competitions”?
Consulting the dictionary, we learned that “Magnus Force” was not a Tom Selleck TV show. Rather, “Magnus Force is the movement of a bullet in the direction it is rotating (and downward) due to the lower air pressure surrounding it. The low pressure pocket is caused by the effect of the bullet’s fast rotation on the surrounding air.” MidwayUSA’s GunTEC dictionary even includes short “bios” of notable firearms inventors and marksmen, including J.M. Browning, Fredrich von Martini, and Peter Paul Mauser. A serious shooting buff could spend hours browsing the GunTEC dictionary, learning new facts (and a ton of obscure trivia.)
October 13th, 2008
Planning an important fall hunt? Here’s a product that will help you pick the most effective bullet for use on big game. The Bullet Test Tube (BTT), an innovative product from Ballistic Technology, allows hunters to test the terminal performance of hunting bullets. This $69.95 unit contains a re-usable wax-like compound that simulates how a bullet penetrates and expands when shot into a game animal. With the BTT, you can measure the wound channel volume (with water), then split the medium in half to measure the wound channel’s length and width. To re-use the BTT, simply melt the wax-like core material in a standard 1.5 gallon crock-pot or large pan and pour it into a replacement cardboard target mold.
Click the screen below to watch a YouTube Video that demonstrates the whole process. (If you are at work, turn down the audio volume first.)
To learn more about the Bullet Test Tube, read this Product FAQ. The Bullet Test Tube has earned the NRA Publications 2007 Golden Bullseye Award and Field & Stream’s 2006 “Best of the Best” Accessories Award. The product is available through major vendors including Cabelas.com, MidwayUSA.com, and Sinclair International.
If you wish to capture the bullet after it passes through the test medium, add the Xtender accessory which slips on the end. This allows hunters to examine bullet integrity as well as wound cavity. Sinclair Int’l prices the Bullet Test Tube at $61.25, while the Xtender is an additional $57.60.
September 28th, 2008
For two years, Forum member John Skowron (John708) has been campaigning a 6BRX, built by Nat Lambeth (RustyStud). You’ll find the full history of John’s 6BRX project in this Forum Thread. With this rifle, John was the overall 1000-yard winner at Butner in February 2007.
The 6mm BRX is based on the 6mm BR cartridge. The shoulder is moved forward, but the shoulder angle and case taper is the same as the parent cartridge. This way you can use standard dies for most purposes (although it is a good idea to have a custom full-length die so you can size the entire case body). Many of our readers have been interested in the 6mm Improved (BRX, Dasher etc.), but they’ve wondered about case durability and barrel life. John has answers for those questions:
6BRX Case Life
Case life running the Berger 105s at 3000+ fps is 14-15 reloads. Brass was discarded when the primer pockets became too loose. The 6BRX brass OAL after fireforming is 1.56″. Max OAL for the 6BRX is 1.58″. The brass never stretched enough to require trimming before discard. Another plus for the 6BRX and Lapua brass. By the way don’t even bother with Remington-brand 6BR brass. The primer pockets were so loose after my standard fire-forming load I had to trash all the cases. Stick with the good stuff, Lapua.
6BRX Barrel Life
Here are Skowron’s comments as his round count increased:
2750 Rounds: I now have 2570 rounds through my 6mm BRX. I was just at the range today doing an accuracy test. I shot two 10-shot groups at 100 yards, one with 105gr Bergers, and the other with 107gr Sierras. Both were identical 0.44″ 10-shot groups. Not bad for a rifle with 2500+ rounds through it.
2900 Rounds: I now have 2900 rounds through my 6mm BRX. I was doing some load testing with the new 6mm Berger bullets. I compared them with my existing comp. load in my 6mm BRX. The 105gr Bergers, jammed .015″ into the lands, with 31.5 grains of Varget and Fed 205s are still shooting .45″ 10-shot groups at 100 yards. Velocity is 3060 fps. I don’t know how long this Broughton barrel will last, but I’m amazed that it’s lasted this long.
2950-3044 Rounds: I had virtually no throat erosion until I reached 2900 rounds. After 2900 rounds throat became noticeably rougher on cleaning and groups opened up. 10-shot groups with match ammo were now .53″ (compared to low fours before). At 2950 rounds the groups ran .58″. At 3044 rounds, the groups opened up to .7″. That’s not enough accuracy for LR work.
CONCLUSION: Barrel life with competitive accuracy was 2900 rounds with this gun.
Achieving this barrel life goal pretty much completes my 6mm BRX project. I’m now shooting a cartridge that has the same or better barrel life than the 260 Rem, it’s more accurate, with essentially equal wind drift. [Editor’s Note: Richard Schatz recently won the NBRSA 1000-yard Nationals with a 6 Dasher, a similar 6BR Improved cartridge, but with a 40° shoulder. Richard’s barrel had over 2000 rounds through it.]
September 17th, 2008
 Well, yes, that headline is a come-on. But there’s truth in the promise. The “miracle device” to which we refer is a simple wind indicator.
Remarkably, many shooters who spend $3000.00 or more on a precision rifle don’t bother to set up windflags when they shoot. Whether you’re a competitive shooter, a varminter, or someone who just likes the satisfaction of drilling small groups, a set of windflags is something you should take to the range every time. And yes, if you pay attention to your windflags, you can easily cut your group sizes in half. Here’s proof…
Miss a 5 mph Shift and Double Your Group Size
In the following table we show the effect of a 5 mph crosswind at 100, 200, and 300 yards. You may say to yourself, “well, I’d never miss a 5 mph let-off.” Consider this — if a gentle 2.5 mph breeze switches from 3 o’clock to 9 o’clock, you’ve just missed a 5 mph net change. What will that do to your group? Look at the table below to find out.
Values from Point Blank Ballistics software for 500′ elevation and 70° temperature.
Imagine you have a 6mm rifle that shoots half-MOA consistently in no-wind conditions. What happens if you miss a 5 mph shift (the equivalent of a full reversal of a 2.5 mph crosswind)? Well, if you’re shooting a 68gr flatbase bullet, your shot is going to move about 0.49″, nearly doubling your group size. With a 105gr VLD, the bullet moves 0.28″ … not as much to be sure, but still enough to ruin a nice small group. What about an AR15, shooting 55-grainers at 3300 fps? Well, if you miss that same 5 mph shift, your low-BC bullet moves 0.68″. That pushes a half-inch group well past an inch. If you had a half-MOA capable AR, now it’s shooting worse than 1 MOA.
If you’ve already invested in an accurate rifle with a good barrel, you are “throwing away” accuracy if you shoot without wind flags. You can spend a ton of money on fancy shooting accessories (such as expensive front rests and spotting scopes) but, dollar for dollar, nothing will potentially improve your shooting as much as a good set of windflags, used religiously.
Which Windflag to buy? Click here to view many windflag designs.
Video from Carbon River Windflags
Aussie Windflag photo courtesy BenchRestTraining.com (Stuart and Annie Elliot).
September 10th, 2008
We’ve all heard the old adage: “Keep your powder dry.” Well, tests by Norma have demonstrated that even normal environmental differences in humidity can affect the way powders burn, at least over the long term. In the July issue of Precision Shooting Magazine, Fred Barker reviews the current Norma and Vihtavuori reloading manuals. Fred notes that, in the Norma manual, Sven-Eric Johansson, head of ballistics at Nexplo/Bofors, presents a very important discussion of water vapor absorption by powder. Johansson shows, with supporting test data, that the same powder will burn at different rates depending on its water content.
Powders Leave the Factory with 0.5 to 1.0% Water Content
Johansson explains that, as manufactured, most powders contain 0.5 to 1% of water by weight. (The relative humidity is “equilibrated” at 40-50% during the manufacturing process to maintain this 0.5-1% moisture content). Importantly, Johansson notes that powder exposed to moist air for a long time will absorb water, causing it to burn at a slower rate. On the other hand, long-term storage in a very dry environment reduces powder moisture content, so the powder burns at a faster rate. In addition, Johansson found that single-base powders are MORE sensitive to relative humidity than are double-base powders (which contain nitroglycerine).
 Tests Show Burn Rates Vary with Water Content
Reviewer Fred Barker notes: “Johansson gives twelve (eye-opening) plots of the velocities and pressures obtained on firing several popular cartridges with dehydrated, normal and hydrated Norma powders (from #200 to MRP). He also gives results on loaded .30-06 and .38 Special cartridges stored for 663 to 683 days in relative humidities of 20 and 86%. So Johansson’s advice is to keep powders tightly capped in their factory containers, and to minimize their exposure to dry or humid air.” Confirming Johansson’s findings that storage conditions can alter burn rates, Barker observes: “I have about 10 pounds of WWII 4831 powder that has been stored in dry (about 20% RH) Colorado air for more than 60 years. It now burns about like IMR3031.”
What does this teach us? First, all powders start out with a small, but chemically important, amount of water content. Second, a powder’s water content can change over time, depending on where and how the powder is stored. Third, the water content of your powder DOES make a difference in how it burns, particularly for single-base powders. For example, over a period of time, a powder used (and then recapped) in the hot, dry Southwest will probably behave differently than the same powder used in the humid Southeast.
Reloaders are advised to keep these things in mind. If you want to maintain your powders’ “as manufactured” burn rate, it is wise to head Johannson’s recommendation to keep your powders tightly capped when you’re not actually dispensing charges and avoid exposing your powder to very dry or very humid conditions. The Norma Reloading Manual is available from a variety of sources, including MidwayUSA.com.
| Real-World Example — “Dry” H4831sc Runs Hotter
Robert Whitley agrees that the burn rate of the powder varies with the humidity it absorbs. Robert writes: “I had an 8-lb. jug of H4831SC I kept in my detached garage (it can be humid there). 43.5-44.0 gr of this was superbly accurate with the 115 Bergers out of my 6mm Super X. I got tired of bringing it in and out of the garage to my house for reloading so I brought and kept the jug in my reloading room (a dehumidified room in my house) and after a few weeks I loaded up 43.5 gr, went to a match and it shot awful. I could not figure out what was going on until I put that load back over the chronograph and figured out it was going a good bit faster than before and the load was out of the “sweet spot” (42.5 – 43.0 gr was the max I could load and keep it accurate when it was stored in less humid air). I put the jug back in the garage for a few weeks and I now am back to loading 43.5 – 44.0 gr and it shoots great again. I have seen this with other powders too.
If you have two jugs of the same powder, one kept in a room in your house and one somewhere else where it is drier or more humid, don’t expect the two jugs of the same lot of powder to chrono the same with the same charge weights unless and until they are both stored long enough in the same place to equalize again. Been there … done that!” |
Do Your Own Test with Sun-Dried Propellants
Johansson studied the effects of humidity variances during long-term storage. Keep in mind that a powder’s water content can change in a much shorter period of time if it is exposed to extreme heat, or if it is used in a very humid environment. You can do your own simple test to show how heat can de-hydrate powder. Throw 100 grains of powder and weigh it. Then put it out in direct sunlight for a full day (shielded from the wind so you don’t lose any kernels). Re-weigh the sun-dried powder. You’ll find it has lost a bit of weight from the water baking out.
September 1st, 2008
As a cartridge case is reloaded multiple times, burnt powder residue and carbon builds up on the inside of the case. Unless the case interior is cleaned in some fashion, eventually you’ll see a reduction in case capacity. One of our Forum members from Australia wonders about the effects of reduced case capacity: “If the capacity of the case decreases as the crud builds up, then it effectively reduces the chamber size. Wouldn’t that change the pressure produced from that of an equivalent clean case?”
Ultrasonic Cleaning Example:
Interesting Test of Case Capacity Changes
Forum member Fred Bohl has actual test results that can help answer the above question. Fred proved that, over a 20-reload cycle, the case capacity of uncleaned cases did, indeed, decline a small amount. However, surprisingly, this did not seem to affect the actual chronographed velocity of the load. ES did increase, but Fred believes the higher ES was due to changes in case-neck tension, rather than due to the slight reduction in case capacity.
Fred reports: “Back when beginning to use ultrasonic case cleaning, part of the motivation was to get the inside clean based on the assumption that allowing burnt residue to build up inside cases would affect capacity, and, ultimately, performance. An experiment was done to test this hypothesis. The load used, 30.5 grains of RL15 behind 107gr SMKs in a 6mmBR, was selected for best group and lowest ES in prior load development. It turned out to be 92% of initial case capacity and neither “full” or compressed. (I would suspect that different powders, load weight, and total case capacity might produce very different results.)
We took 30 cases of identical initial capacity and tracked three lots of 10 each:
LOT 1: No Internal cleaning
LOT 2: Cleaned with media in tumbler
LOT 3: Cleaned with Ultrasound machine
Each case (in each lot) was shot and reloaded 20 times. The simplified results after 20 reloads of each lot were as follows:
Lot 1 (not cleaned) – 0.3 to 0.4 gr. loss of capacity, 5 to 8 fps greater ES.
Lot 2 (tumble cleaned) – 0.1 to 0.3 gr. loss of capacity, 4 to 6 fps greater ES.
Lot 1 (ultrasonic cleaned) – no loss of capacity, no detectable change in ES.
FINDINGS
There was no detectable correlation of velocity change to the lots. An oddity was that on very hot days Lot 1 velocities were, occasionally, slightly higher. [Editor’s note: That does suggest that the carbon build-up inside the uncleaned cases might cause a slight increase in pressure that shows up on hot days. Fred has posted that “A local shooter reported doing the 20 reload, no clean test on a .308 that gave a loss of capacity of 2.0 grains, doubled ES and signficant velocity changes. However, I don’t have any details on his load weight or powder.”]
NOTE: From results of another ongoing test, I believe the above differences in ES are probably due more to variance in bullet grip tension than case capacity. The ultrasound cleaned cases (LOT 3) did maintain the lowest ES, but we are not 100% sure of the reasons why. More consistent bullet seating might be the reason.
[Editor’s comment: Jason found that with his ultrasonically-cleaned cases, the inside of the necks got so “squeaky clean” that he needed to use dry lube in the necks. Jason uses the $10.95 dry lube kit from Neconos.com. This applies ultra-fine Moly powder to the neck using small carbon steel balls]
August 31st, 2008
Gunsmith Nat Lambeth (“RustyStud” on our Shooters’ Forum) offers the following advice for readers who need to ship rifles or major gun components (actions, barrels etc.) to gunsmiths or repair facilities.
“You have several options when shipping your guns to and from a Gunsmith. I’ve tried them all and had problems with them all. Here are some pointers:
1. Always package your unloaded firearm so that it is not loose and can’t work itself loose during transport. I recommend, at minimum, you use a hardcase inside a cardboard box. You can order a hard case from any of the 6mmBR.com website catalog advertisers. It will come in a nice cardboard box. Just open the end and slide it out. Put your gun in the plastic hard case (after oiling the metal parts) and slide it back into the box. Then tape and relabel the box. Make sure marking on the box does NOT identify the contents as a gun. (You may be required to identify the contents to the shipping company or U.S. Postal Service clerk however.) For a very expensive gun, consider using a wood shipping crate. I will be making some shipping cases from plywood and foam line them. I will have to charge my customer a deposit and when they return the shipping crate I will return their deposit.
2. Pack individual components carefully, and enclose them in separate bubble wrap (or styrofoam) if there is any chance the parts can contact one another. Your editor had an experience where the finish of a fine, blued handgun was ruined because the repair facility had placed old, replaced trigger parts loosely in a foam-lined case with the handgun. During shipping these spare parts worked back and forth, gouging and scratching the pistol.
 
3. Confirm the recipient’s address BEFORE you ship. Individuals and businesses change locations all the time. Don’t assume an address you used a few months ago is still valid. It’s tempting to use old addresses that are pre-configured in the UPS or Fedex web-based shipping programs, but you should always confirm address validity prior to shipping.
4. Always put the sender’s and recipient’s telephone number on the outside of the box with the address. I have neighbors call me all the time saying I have a box that was delivered to them by mistake. If there is any way the label could be torn off or ripped, write the number on the cardboard with a felt pen.
5. Always send your packages insured for full replacement value. Take time-dated pictures of the contents before you ship. (This is yet one more reason to get an inexpensive digital camera, such as the Canon A590IS.) If you’re shipping a firearm with special collectors’ value, deluxe wood, or engraving, be sure you have detailed, high-quality photos of the item so you can prove its worth.
6. Always send firearms and expensive components “Adult Signature Required” if by FedEx, UPS, or DHL. If they are sent via U.S. Postal Service, send them restricted delivery. This insures a tracking number and verification they got to their destination. If you ship USPS, it’s not a bad idea to pay a little extra for the green return receipt. That’s one more piece of evidence that works in your favor if the recipient claims non-delivery. The green card also reminds the carrier to confirm the address.
7. Keep all your shipping documentation for a year after the package has been received. There could be a unseen damage that turns up several months down the road. This illustrates the importance of carefully inspecting items you receive immediately. Don’t let a box sit around for days before you open it.
8. Handguns are by law required to be sent by common carrier (unless you are an FFL holder). Most of the common carriers have their own rules requiring overnight or next day delivery. Long guns can be sent by ground and you can use the U.S. Postal Service. Companies such as FEDEX and UPS may try to stick you with a higher cost shipping bill by claiming that rifles and shotguns must go next day or air. That is not true. Long guns can be shipped via ground. Do check local laws however–California has special rules regarding ARs and registered “assault weapons”.
 9. Keep an eye on your gun by monitoring the tracking number. You can do this online with FEDEX, UPS, and USPS. If your package does not reach its intended destination, when it is supposed to be there, then initiate a traceright away. Don’t wait.
When Something Goes Wrong–Filing Claims
In my experience it takes from 7 days to 10 months to get a settlement on a claim. Don’t hesitate to take a shipper to small claims court if necessary. If the shipper gives you the run-around, filing a small claims action may be the best $40.00 you can spend. It only costs $40.00 to start a small claims action and the subpoena is another $5 bucks. Usually sending a subpoena to an officer will result in a rapid settlement. It is cheaper for the carrier to settle than have their corporate bigwig stuck in some small claims action. Realize the carrier usually is not the insurer.
I have had two claims within the last 10 weeks and neither has been settled yet. In both cases the barelled action was double-boxed ,and in one case it was also inside a piece of schedule 80 PVC pipe and was broken. The other was in a double-walled cardboard box. The action was bent at the action barrel juncture, it now looks like a boomerang. The muzzle was pushed through six layers of double wall corrugated box.
I quit using UPS over a year ago. Depending on how FEDEX settles these last two claims, I’ll decide whether I use their services again. Your editor prefers FEDEX as he has found that they paid non-delivery claims swiftly and at full value. One thing for sure, if you use USPS you have the Postal Inspectors and the BATF looking for your gun if it is lost.”
August 25th, 2008
Some folks feel that they don’t have to worry about rust and corrosion on stainless steel barrels, actions, and other components. That’s not really true. “Stainless” is a bit of a misnomer. First, there are different types of stainless steel alloys, with different degrees of rust resistance. 300 series stainless is more corrosion resistant than the 416 stainless commonly used in barrels. The composition (by percentage weight) of 416 stainless is 0.15% carbon, 12-14% chromium and the rest iron. 416 stainless steel lacks the roughly 10% nickel content that makes the 300 series more corrosion resistant in atmospheric conditions.
Though some grades of stainless are more corrosion-resistent, ALL varieties of stainless steel can rust if they are not handled and stored properly. Forum reader Kells81 observed: “Wanna see some rusted stainless? Go to the big “C” brand store in Ft. Worth. Every stainless gun they have on the used gun rack is rusted.” Tom Easly of TRE Custom explains: “Sweat is very corrosive. Sweat and blood will rust many stainless steels. I hate to handle my guns or drip on them when I sweat. It really helps to just wipe them good with a wet rag, dry and wipe on a light coating of gun oil. I think most stainless barrels are made from type 416 stainless, and it is generally pretty corrosion resistant, but not when exposed to sweat, blood, or chlorates (corrosive priming), and some other electrolytes.”
Forum member Jacob, who is studying materials science at LSU, provides this technical information: “The basic resistance of stainless steel occurs because of its ability to form a protective coating on the metal surface. This coating is a ‘passive’ film which resists further ‘oxidation’ or rusting. The formation of this film is instantaneous in an oxidizing atmosphere such as air, water, or other fluids that contain oxygen. Once the layer has formed, we say that the metal has become ‘passivated’ and the oxidation or ‘rusting’ rate will slow down to less than 0.002″ per year (0.05 mm per year).
Unlike aluminum or silver, this passive film is invisible in stainless steel. It’s created when oxygen combines with the chrome in the stainless to form chrome oxide which is more commonly called ‘ceramic’. This protective oxide or ceramic coating is common to most corrosion resistant materials.
Halogen salts, especially chlorides, easily penetrate this passive film and will allow corrosive attack to occur. The halogens are easy to recognize because they end in the letters ‘ine’. Listed in order of their activity they are: fluorine, chlorine, bromine, iodine, astatine.
These are the same chemicals that will penetrate Teflon and cause trouble with Teflon coated or encapsulated o-rings and/ or similar coated materials. Chlorides are one of the most common elements in nature and if that isn’t bad enough, they’re also soluble, active ions. These provide the basis for electrolytes. The presence of electrolytic solutions can accelerate corrosion or chemical attack.”
 CONCLUSION: Stainless steel barrels and components won’t rust nearly as fast as blued steel, but you still have to take precautions — particularly removing sweat and corrosive salts from the barrel. Also, don’t let moisture build up inside or outside of the barrel.
We recommend wiping your barrels and actions with Eezox, or Corrosion-X after each use. These are both extremely effective rust-fighters that go on thin, without leaving a greasy residue. (Eezox leaves a clear finish, while Corrosion-X has a slightly waxy finish.) Also store your guns in Bore-Store synthetic bags when the guns go in the safe. Bore-Stores wick away moisture, and the synthetic fleece inner surface is treated with rust-fighting chemicals. Bore-Stores also protect your guns against dings and scratches. To discuss rust formation on stainless steel, visit this FORUM Thread.
August 24th, 2008
This may surprise you. We’ve learned that time (between neck-sizing operation and bullet seating) can have dramatic effects on neck tension. 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 over twice as much force was required to seat the bullets 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 correspond to pounds of force applied to the bullet). Conclusion? In the two weeks that had elapsed since neck-sizing, the necks continued to get tighter and stiffen.
Lesson learned: For match rounds, size ALL your cases at the same time. If you want to reduce neck tension, load immediately after sizing.
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